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2015 08 Power Engineering

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2015 08 Power Engineering

  1. 1. HARNESS THE POWER RENTECH engineers build unmatched power and performance into every boiler we deliver. Our 80-acre manufacturing facility—the industry’s most technologically advanced—includes heavy bay and light bay areas with direct access to rail, cross-country trucking routes and shipping facilities. We master every detail to deliver elemental power for clients worldwide. Take an expanded tour of our facilities today at www.rentechboilers/facilities. HARNESS THE POWER WITH RENTECH. OF MANUFACTURING INNOVATION HEAT RECOVERY STEAM GENERATORS WASTE HEAT BOILERS FIRED PACKAGED WATERTUBE BOILERS SPECIALTY BOILERS WWW.RENTECHBOILERS.COM
  3. 3. KIEWIT.COM Powering the future. An industry innovator, Kiewit Power has extensive experience in the gas-fired, air quality control systems, power delivery, renewable and nuclear markets. We offer clients a one-stop shop for all integrated engineering, procurement, construction and startup service needs. Our industry-leading projects show how Kiewit is committed to remaining a power pioneer. Kiewit Power Group Inc. 9401 Renner Boulevard Lenexa, KS 66219 (913) 928-7000 Shepard Energy Centre Calgary, Alberta For info. http://powereng.hotims.com RS# 1
  4. 4. CHIEF EDITOR — Russell Ray (918) 832-9368 russellr@pennwell.com ASSOCIATE EDITOR — Sharryn Dotson (918) 832-9339 sharrynd@pennwell.com ASSOCIATE EDITOR — Tim Miser (918) 831-9492 tmiser@pennwell.com CONTRIBUTING EDITOR—Brad Buecker CONTRIBUTING EDITOR—Brian Schimmoller CONTRIBUTING EDITOR—Robynn Andracsek CONTRIBUTING EDITOR—Wayne Barber (540) 252-2137 wayneb@pennwell.com CONTRIBUTING EDITOR—Barry Cassell (804) 815-9186 barryc@pennwell.com GRAPHIC DESIGNER — Deanna Priddy Taylor (918) 832-9378 deannat@pennwell.com SUBSCRIBER SERVICE P.O. Box 3264, Northbrook, IL 60065 Phone: (847) 763-9540 E-mail: poe@halldata.com MARKETING MANAGER — Rachel Campbell (918) 831-9576 rachelc@pennwell.com SENIOR VICE PRESIDENT, NORTH AMERICAN POWER GENERATION GROUP — Richard Baker (918) 831-9187 richardb@pennwell.com NATIONAL BRAND MANAGER — Rick Huntzicker (770) 578-2688 rickh@pennwell.com CHAIRMAN — Frank T. Lauinger PRESIDENT/CHIEF EXECUTIVE OFFICER — Robert F. Biolchini CHIEF FINANCIAL OFFICER/SENIOR VICE PRESIDENT — Mark C. Wilmoth CIRCULATION MANAGER — Linda Thomas PRODUCTION MANAGER — Katie Noftsger POWER ENGINEERING, ISSN 0032-5961, USPS 440-980, is published 12 times a year,monthly by PennWell Corp.,1421 S.Sheridan Rd.,Tulsa, OK 74112; phone (918) 835-3161. ©Copyright 2015 by PennWell Corp. (Registered in U.S. Patent Trademark Office). All Power Engineering published content is copyright protected by law. PennWell Corporation must grant proper authorization to reuse any article, photograph or illustration. Foster Printing is the exclusive reprint provider for Power Engineering and gains copyright permissions for published content. For copyright permissions, call 866-879-9144 x194. Prior to photocopying items for educational classroom use, please contact Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923 USA 978-750-8400. Periodicals postage paid at Tulsa, OK and additional mailing offices. Subscription: U.S.A. and possessions, $111 per year; Canada and Mexico, $124 per year; international air mail, $300 per year. Single copies: U.S., $18, Outside U.S. $29. Back issues of POWER ENGINEERING may be purchased at a cost of $18 each in the United States and $29 elsewhere. Copies of back issues are also available on microfilm and microfiche from University Microfilm, a Xerox Co., 300 N. Zeeb Rd.,AnnArbor,MI 48103.Available on LexisNexis,Box 933,Dayton, OH 45402; (800) 227-4908. POSTMASTER: Send change of address, other circulation information to POWER ENGINEERING, PO Box 3271, Northbrook, IL 60065-3271. “POWER ENGINEERING” is a registered trademark of PennWell Corp. Member American Business Press BPA International PRINTED IN THE U.S.A. GST NO. 126813153 Publications Mail Agreement No. 40052420 CORPORATE HEADQUARTERS—PennWell Corp. 1421 South Sheridan Road • Tulsa, OK 74112 P.O. Box 1260, Tulsa, OK 74101 Telephone: (918) 835-3161 • Fax: (918) 831-9834 E-mail: pe@pennwell.com World Wide Web: http://www.power-eng.com Power Engineering® Power Engineering is the flagship media sponsor for FEATURES 119VOLUME POWER ENGINEERING ONLINE : www.power-eng.com Newsletter: Stay current on industry news, events, features and more. Newscast: A concise, weekly update of all the top power generation news Industry News: Global updates throughout the day DEPARTMENTS 2 Opinion 4 Gas Generation 6 View on Renewables 8 Energy Matters 10 Nuclear Reactions 48 Ad Index 18 A New Era of Demand Response Demand response capability in North America has grown considerably in the past five years,both at utilities and within competitive markets.Learn how the use of DR in grid planning and operations has solidified as utilities rely on DR to meet installed capacity requirements and operating reserve requirements. 36 Valves & Actuators Power plants use hundreds of valves and actuators as the final control elements in their operations.Power Engineering examines the different types of valves and actuators and the advancements that are allowing them to operate at higher pressures,temperatures,and frequency. 28 Dense Slurry Coal Ash Management: Full Compliance, Lower Cost, Less Risk New CCR and ELG rules promise to significantly impact waste management in the coal-fired power industry.Learn how the Circumix™ Dense Slurry System mixes wastewater with CCRs to produce a stable product with near-stoichiometric use of water. 42 Water’s Journey More than ever,waste water from power plants must be viewed holistically,from the beginning of its journey through the facility, all the way to its final discharge.Learn how increasingly stringent wastewater regulations are forcing plant personnel to consider complex treatment methods to comply with regulations. 12 The Fall of the F-Class Turbine For the first time in over 20 years,F-Class turbine technology no longer commands majority share in the NorthAmerican 60-Hz, heavy-duty gas turbine market.Find out why the trend toward G-,H-,and J-class turbines is here to stay. No.8,August 2015
  5. 5. 2 OPINION www.power-eng.com prices dropping 48 percent by 2040. Talk about a tipping point. These new economic dynamics, along with other technology and cost advances particularly in energy storage, are why states, cities, corporations, and nations can now set once-unthinkable targets forgenerationfromrenewableswithout breaking the bank. In more news from the month of June, Hawaii (100 percent by 2045) and Vermont (75 percent by 2032) both signed unprecedented renewable portfolio standards into law. And in California, the state senate passed Gov. Jerry Brown’s goal of 50 percent renewables generation by 2030. It now awaits expected approval by the state assembly. Policy drivers like these will continue to be critical to drive the growth of renewables. In one piece of bad news on the policy front at the end of June, the U.S. Supreme Court issued a key ruling against EPA regulation of mercury emissions from coal-fred power plants. It’s certainly not a good development for the environment, but unlike what I’ve read in various media accounts, it does not directly affect CO2 regulation such as the EPA’s Clean Power Plan. The court’s ruling does not change the fundamental economics of energy: coal is simply no longer a cost-effective choice for new generation in the U.S. and increasingly, overseas as well. Compared to the much larger trends in fnance and policy that are driving the momentum of renewables, many of which came to the fore in June, I predict that this SCOTUS decision will be a blip on the radar. L ast month, we Americans cel- ebrated our nation’s birthday, capped off perfectly by the USA women’s soccer team’s sensational 5-2 victory in the World Cup final. As we hit the halfway point of 2015, the clean-energy industry also has much to celebrate, much of it in the month of June alone and much of it financial. Consider all of these recent developments: • The White House announced $4 billion in clean-energy funding commitments, including $1.1 bil- lion from five large institutional investors such as the University of California and TIAA-CREF, with the balance from major founda- tions and nonprofits. • Bill Gates quite literally doubled down on financing innovative renewables technologies. The software mogul-turned-clean en- ergy investor told the  Financial Times he would add an additional $1 billion over the next five years to his $1 billion already invested in clean-tech companies and the venture capital firms that back them. • Another tech mogul, Masayoshi Son of Japanese telecom giant Softbank, went even further. Al- ready a major funder of large solar energy projects in Japan, Softbank committed $20 billion for solar in India — aiming to help grow that market to 100 GW in 2022 from 3 GW today. • Sixty percent of large investment firms plan to invest in solar pow- er projects for the first time in the next five years (including 32 per- cent in the next year), according to a survey released in June by solar PPA market maker Wiser Capital. Eighty percent said they want to “support a clean-energy future” and more than 60 percent are con- fident in the chances of high ROI. At the end of June, China upped its commitment to reduce greenhouse gas emissions by 60-65 percent from 2005 levels by 2030, including a goal to receive 20 percent of its primary energy from non-fossil fuels by 2030. The announcement was part of a slew of new GHG cut commitments from the U.S., Brazil, and South Korea, in advance of the United Nations climate talks in Paris later this year. A great driver of all of this recent momentum is the rapidly changing economics of clean energy. Headlines about record-low prices for solar and wind power in a myriad of regions appear almost daily. To cite just two examples, Michigan utility DTE Electricity has asked regulators to approve a rate cut because of falling wind prices in the state, while Austin Energy, seeking to procure 600 MW of solar in Texas, received developer bids at less than 4 cents per kilowatt-hour. Those are just two examples of a broad-based global trend that shows no signs of slowing down. A June report from Bloomberg New Energy Finance predicts that wind power will become “the least-cost option almost universally” within 10 years, with prices falling 32 percent by 2040. And solar will join wind as cheaper than fossil fuel-fred energy by 2030, with Fireworks, a World Cup, and Clean Energy MomentumBY CLINT WILDER, CLEAN EDGE Author Clint Wilder is senior editor at clean-tech research and advisory frm Clean Edge and the coauthor of two books: “Clean Tech Nation: How the U.S. Can Lead in the New Global Economy” and “The Clean Tech Revolution.”
  6. 6. For info. http://powereng.hotims.com RS#2
  7. 7. 4 GAS GENERATION www.power-eng.com I was surprised to learn that an ul- tra-complex bit of precision engineering, with a final price tag that can reach many millions of dollars, would ultimately de- pend on good old-fashioned air to keep itself from melting down onto the boots of the engineers. “The air-cooled version of the turbine is just much simpler and more cost-effec- tive,” Abate told me. “The steam-cooled turbine was technical- ly elegant, but it was expensive to operate. Air cooling makes the turbine cheaper to maintain because there are no steam circuits to tear down before accessing key components. That adds up to lower life cycle costs.” In fact, air-cooled turbines are very common in the industry. While air- cooled designs do require hot air to be extracted from the gas turbine to cool hot-path components, and the theft of this heat can compromise their overall efficiency, they can still be preferable to steam-cooled designs which do not incur such performance penalties, if only for their simplicity and lower operation and maintenance costs. So what’s old is new. It turns out GE’s turbines are far from the only ones in the industry to rely on such tried-and- true engineering; Siemens and Alstom (among others) also produce air-cooled gas turbines, and it’s safe to bet that other companies are right now putting new air- cooled designs through the paces in R&D labs across the world. I guess sometimes simpler really is better. W hen I was a teenager, I dat- ed a girl whose parents wouldn’t let her dress grun- ge. Having grown up in another era, her mom couldn’t understand the movement I suppose, and she flatly outlawed such foolishness in the house. Did people real- ly wear plaid flannel and cut holes in their jeans intentionally? The whole episode became a major problem for us. (Actually, it created an existential crisis worthy of Kierkegaard’s storied prose.) Admittedly, it was the mid-nineties, and Nirvana had been over and done with for a couple years. But fashion moves more slowly in a little farm town, and grunge was still very much in vogue where we lived. Not to worry though. This was no av- erage girl, and she quickly found an en- terprising solution to her problem. If she couldn’t dress grunge, she would find an- other counter-cultural fashion statement that her mom could relate to, and drag it kicking and screaming into the modern era. She would dress like a hippy. This girl was committed. We’re talking full-on Haite and Ashbury here. It was a circus! But come on, dressing like an anachro- nistic hippy? That’s so amateurish, and we were better than that. Enter the mid-60s Volkswagen Beetle. Yes, as it happened, the neighbor up the road was selling his pitiful little bug for a pittance, so my girlfriend paid the few hundred dollars he was asking and drove it home that weekend. It was baby blue, and that afternoon she sent away for the mandatory flower decals to stick on the hood. She let me drive it a time or two. You had to stand on the clutch to shift into reverse, but other than that it handled like a dream—a fever-fueled, hallucinogenic nightmare of a dream. We drove that thing up and down the back roads all over the county. It was awe- some…and terrifying. Here’s a hint though. If you’re going to park your cranky geriatric bug at the local drive-in burger place, shut the engine off. Turns out vintage Beetles were air-cooled, and idling one in a stationary position long enough to eat a double quarter-pound- er with cheese will ren- der it hotter than an Oklahoma July. Can I really be the only per- son in the world who didn’t already know this? Next someone will try to convince me that VW put the trunk in the front of the blasted thing. A few years ago I learned Volkswagen would be ending the manufacture of their original air-cooled masterpiece. Sure, the company had already come out with a re- placement—the “new” Beetle—but it was thoroughly modern and water-cooled, so it wasn’t the same. Yes, it seems the evolu- tion of internal combustion engines has unfailingly included an upgrade from air- cooled to fluid-cooled systems. But not so with natural gas-fired turbines, it seems. Last year, I had the pleasure of speaking with Victor Abate, president and CEO of power generation products at GE Power & Water. We were talking about GE’s HA turbines, which are among the largest and most efficient in the world. Unlike GE’s previous H-class turbines which utilized steam cooling, GE’s new HA turbines rely on air for temperature regulation. (The “A” stands for air, in fact.) Economy from Thin AirBY TIM MISER, ASSOCIATE EDITOR Air cooling makes the turbine cheaper to maintain because there are no steam circuits to tear down. - Victor Abate, GE
  8. 8. Raising performance in power plant operation The new release of SPPA-T3000: Success starts in the control room PGIE-A10011-00-7600 Get in touch: Our new release of SPPA-T3000 is infused with innovations specially designed for more effectiveness and efficiency in operation. Supporting operators with the right tools, targeted cues, and guided procedures, it provides the platform to increased power plant performance. Experience our worldwide leading SPPA-T3000 control system. New release siemens.com/sppa-t3000 For info. http://powereng.hotims.com RS#3
  9. 9. 6 VIEW ON RENEWABLES www.power-eng.com capacity limits and are struggling with T&D networks critically in need of up- grades. The world may not be entirely ready to change the way it sources electricity. It will need to get ready because the conven- tional energy status quo needs to adjust rapidly in order to realize true energy in- dependence for all. True energy indepen- dence will not rely 100 percent on the electricity grid and it will look a lot more like off grid solar. The current focus on mi- cro grids, under the defi- nition that micro grids include storage, is the off grid model. True inde- pendence will encourage electricity conservation and include edu- cating electricity users about the photo- voltaic/storage systems that allow them to decouple from the utility grid when necessary. The slow, messy changing of the elec- tricity guard will also include altering the antiquated concept of what utilities are and what utilities should provide. De- ployment of PV is often antithetical to the utility model – simply put, it cuts into the utility revenue model. The slow messy changing of the electricity guard will force electricity users to become responsible for their electricity future and this is not a bad thing. All industrial and technological changes cause seismic ruptures in the status quo and this one will be no dif- ferent. The results of this change will be a seismic correction. C onventional energy technolo- gies and investors in big oil, nat- uralgasandcoalarehighlyresis- tant to letting insurgent renewable energy technologies such as solar and wind take the lead. No matter, squint your eyes and the energy future with renewable energy as the dominant technology is visible over the horizon – hazy and still a bit far off, but visible. Currently, renewable ener- gy’s share of global energy production is a fraction of conventional energy’s share but change is slowly taking hold despite well-funded resistance to it. The global photovoltaic industry has a leading role to play in this messy chang- ing of the energy guard. It’s been playing a role for decades, though it has seldom been easy and rarely highly profitable. Viewed simply through the lens that growth is always good, decades of neg- ative or low margins could be written off as the price of gaining share, though it should be remembered that PV has a very small share of global electricity production. There is another perspective with which to view decades of PV industry behavior, that of courageous persever- ance in the face of well-funded (con- ventional energy) competition. This perspective is also true. Photovoltaic industry participants have persevered through slap dash and unreliable in- centives, drastic, abrupt and some- times retroactive changes to incentives, end users waiting for the technology to mature and many others miss or poor understandings of the technology and industry. In truth, the global photovoltaic industry has persevered through decades of double digit growth and decades of fi- nancial struggle. The availability of government legis- lated incentives is a fragile and unreliable thread on which to hang the hopes and dreams of an entire industry. Sudden and retroactive changes have broken the hearts and bank balances of many a PV industry participant. Yet, deployment often contin- ues despite the cessation of an incentive primarily because, simply, it must. It would be more fiscally devastating than many realize if deployment ceased abruptly. There is significant inventory on demand and supply sides of the solar industry and if deployment ceased, it would become even more of a burden. Jobs would be lost. Research and development would stall. Continued deployment, however, is different from profitability. Incentives are expensive to support, and when governments in Europe be- gan pulling the incentive-rug out from under the PV industry this, along with fallout from pricing set below cost, stimulated an industry-wide consol- idation that included the failure of many well-known and industry lead- ing companies. Currently with deployment of renew- ables (and PV) encouraged by govern- ments and end user interest at a high lev- el, utilities are pushing back on continued accelerated deployment while globally, utility grids have been pushed to their The Slow, Messy Changing of the Electricity Guard BY PAULA MINTS, SPV MARKET RESEARCH “True energy independence will not rely 100 percent on the electricity grid and it will look a lot more like off grid solar.”
  10. 10. A World of Solutions Visit www.CBI.com 2015 MEDAL RECIPIENT THE TEAM YOU TRUST As a fully integrated engineering, procurement and construction contractor, CB&I can handle your gas generation project from start to finish. Our complete service offerings include engineering, procurement, pipe and steel fabrication, construction and maintenance. Today’s fast moving generation market requires a team that can deliver with certainty. When it comes to constructing new gas generation facilities that are reliable and cost effective, trust CB&I’s in-depth market knowledge and industry leading experience. ADVANCED CLASS TURBINES PRICE AND SCHEDULE CERTAINTY INTEGRATED SUPPLY CHAIN SOLUTIONS EXTENSIVE CRAFT RECRUITMENT/MANAGEMENT EXPERIENCE Contact CB&I at +1 704 343 7500 to learn how our complete solutions in gas power generation can benefit your next project. For info. http://powereng.hotims.com RS#4
  11. 11. 8 ENERGY MATTERS www.power-eng.com design that has tripped up many owners during permitting. Air permits include separate limits when operating with and without duct firing. Typically the max- imum amount of duct firing is set by either the desired amount of peak plant output or the maximum practical design limit. Often, preliminary engineering is completed to estimate the amount of duct firing that is required to achieve one of these limits. Emissions produced during duct firing are calculated based on this heat input. However, the actual required amount of duct firing is determined by fi- nal major equipment OEM selection and thermal cycle design optimization. The fi- nalization of these two decisions is often completed after air permit issuance. This may result in limitations on duct firing capability. In this case, it is important that the design engineers determining cycle design and the permitting engineers de- veloping emissions estimates understand and consider the impact various major equipment OEMs and variations in cycle design may have on heat input and asso- ciated permit limitations. Gas turbine technology is evolving at a rapid pace. In the past three years, most of the major gas turbine OEMs have released several performance improvements. Many owners, especially those with proj- ect delays or longer permit approvals, have been caught with air permit require- ments restricting the ability to implement the latest gas turbine technology platform without revising the air permit. The is- sues described above can be mitigated or eliminated when the permitting and the design engineers communicate. Coordination up front can save time and money in the end. T he battle for a good permit be- gins well before the application is submitted, with the initial Front End Engineering Design (FEED) and development of conceptual engineer- ing information used as inputs to permit modeling and development. A lack of communication between per- mitting and design engineers can lead to big problems for a facility, as each group has its own perspective, language, drivers, and needs. Ultimately however, align- ment between permitting and design en- gineers will best serve the long term inter- ests of the facility. Particulate emission limits are a fre- quent sourceofpermitting/designdiscon- nect. A major contributor to condensable particulate matter (PM) is the amount of sulfur in the fuel gas and the amount of oxidation of sulfur dioxide (SO2 ) that oc- curs through the gas turbine combustion process. This occurs throughout the heat recovery steam generator (HRSG) in the selective catalytic reduction (SCR) sys- tem, carbon monoxide (CO) catalyst, and duct burner. The maximum amount of sulfur in the gas may not be easy to define over the life of the plant. Conservatively using the sulfur tariff for the gas pipeline is often too high an assumption and can lead to serious impacts during dispersion modeling, especially considering that the actual gas sulfur content is typically sig- nificantly lower than tariff value. How- ever, owners are often hesitant to rely on past gas supply sulfur levels as a reliable prediction of long term levels, as several shales predict a potential for increasing sulfur content as production areas shift. The type and location of SCR and oxi- dation catalyst impacts the conversion of SO2 to sulfur trioxide (SO3 ) through- out the gas turbine/HRSG train, and the amount of ammonia injection and slip impacts the amount of SO3 in the ex- haust gas that is converted to ammonium bisulfate. Because conversion of SO2 to SO3 is not widely understood, most own- ers are prudent to assume 100 percent conversion of sulfur to particulate when establishing their plant PM limit. Start-up emissions are another area of concern. Actual hot, warm, and cold start- up emission rates are highly dependent on the gas turbine manufacturers (OEM) and starting package selection, the HRSG and steam turbine generator design, OEM selections, the overall steam cycle design, and balance of plant equipment design. “Conventional” start-up times are based on holding the gas turbine at select, low operating loads to allow the HRSG ma- terials to gradually warm. These hold points also provide time for cycle water quality to be brought within specifica- tion before steam can be admitted to the steam turbine. This typically results in the gas turbine operating outside of emissions compliance load during start- up with NOx, CO, and VOC emissions at orders of magnitude higher than during normal steady state operation. An alter- native is to remove the gas turbine low load hold points and reduce the overall startup emissions. It is also important to understand how to appropriately esti- mate start-up emissions for the final plant configuration. Calculation of start-up emissions is not easy. Regardless of major equipment selection, start-up emissions are highly dependent on, and influenced by, the overall cycle design. Duct firing is another element of plant FEEDing the Permitting Beast BY MEGAN PARSONS, BURNS & MCDONNELL, AND ROBYNN ANDRACSEK, P.E., BURNS & MCDONNELL AND CONTRIBUTING EDITOR Megan ParsonsRobynn Andracsek
  12. 12. Duct Burner2 H.P. Superheater4 H.P. Evaporator5 H.P. Steam Drum15 L.P. Vent Silencer16 H.P. Vent Silencer14 L.P. Steam Drum w/ Integral Deaerator17 Distribution Grid1 Observation Port3 Injection Grid7 S.C.R.8 C.O. Catalyst6 H.P. Economizer10 L.P. Superheater11 H.P. Evaporator9 L.P. Evaporator 13 DA. Pre-Heater 12 Stack18 H.P. Steam Outlet L.P. Superheater Outlet BESTSUITED FORGAS TURBINESUP TO120+MW. In addition to designing and manufacturing world-class industrial boilers, Victory are custom-engineered for combined combined cycle applications. VEO HORIZON Æ Gas-Turbine HRSG Because of the current demand for small to Æ . Work directly with industry experts known worldwide for providing proven cutting edge emissions and enhanced construction. Call 918.274.0023 WWW.VICTORYENERGY.COM - 10701 EAST 126TH STREET NORTH, COLLINSVILLE, OKLAHOMA 74021 F O L L O W A L E A D E R Expect the Best from For info. http://powereng.hotims.com RS#5
  13. 13. 10 NUCLEAR REACTIONS www.power-eng.com so future leaders can see what may be available to them and how. Line leaders’ routines need to include succession planning, development and coaching in addition to the routines they use to run the plant. Leaders must serve as role models in the time they spend developing their own succession candidates as well as coaching and mentoring others. Leadership development and train- ing programs must be seen as effective by participants and sponsors. Leadership roles at the site need to be viewed as desirable opportunities by potential succession candidates. If not, site leaders need to figure out why. Line leader and HR roles and respon- sibilities should be documented, under- stood clearly and executed accordingly. HR personnel assigned to talent management and leadership develop- ment roles must be highly capable and viewed as effective by line leaders. Assessments of succession candidates and potential leaders need to be con- ducted by trained professionals who understand what nuclear power de- mands from talent to be successful. Decisions about leadership changes and promotions should be made me- thodically, with adequate input from all appropriate parties. Overall program effectiveness re- views need to be conducted regularly, focusing on process, behavior and re- sults. Although these requirements may appear demanding, the more successful utilities are following them and have made strategic decisions to invest in the leadership capabilities necessary to run nuclear plants effectively. T he cover story in the June issue of Power Engineering magazine highlighted the challenges facing the energy, utility and manufac- turing sectors in finding skilled labor as baby boomers retire in greater num- bers. These same challenges are being seen in the supervisor and manager ranks at nuclear power plants across the country. Engineering—more than any other department—appears to be the canary in the coal mine. Engineer- ing organizations are feeling the loss of knowledge and the impact of too many open engineering positions and leadership roles filled by much less ex- perienced engineering supervisors and managers. As U.S. nuclear power plants and their systems age and license exten- sions go into effect, the need for highly capable engineering leadership will in- crease, if anything. Operations departments are not feel- ing as much pain as engineering be- cause sites have been more diligent and proactive in feeding the licensed opera- tor and non-licensed operator pipelines or face being out of compliance with their legal commitments for operating the reactor. Maintenance, work man- agement and training organizations are right behind engineering in struggling to fill open positions with qualified professionals and capable supervisors. As nuclear operating companies make short- and long-term asset man- agement decisions about what equip- ment to replace, fix, or maintain, they need to be making strategic decisions about investing in the talent they need to effectively run organizations as com- plicated as nuclear power plants. On the surface, most nuclear utilities across the U.S. appear to be doing so, in that they have recruiting, assessment, and lead- ership development programs in place conceivably to grow talent and increase leadership effectiveness. But scratch below the surface, and many programs fail to reach a large portion of nuclear power leaders and potential leaders. Leadership training programs may be limited in their effectiveness and/or not available to a large portion of the pop- ulation. Succession planning, critical to focusing developmental activities, too often consist of lists of names repeated too often and discussions concentrated on personality and historical personal references, good and bad. Instead, suc- cession planning discussions need to be regular meetings, supported by the highest levels of leadership, and cen- tered on leadership attributes necessary to be effective. Candidates’ level of read- iness should be based on independent assessments of these attributes, which also serve as a basis for future leaders’ development. Some companies are applying the necessary discipline and rigor to talent development in order to close gaps and grow their own talent, forestalling lead- ership shortages. In my book, Nuclear Energy Leadership: Lessons Learned from U.S. Operators (2013), I offered a checklist that nuclear sites can use to identify where they need to work to improve their talent development capa- bilities: The site must have documented pro- cesses for succession planning, talent management and leadership develop- ment. Leaders need to follow these pro- cesses and communicate about them with the broader management team Strategic Investment in TalentBY MARY JO ROGERS, PH.D. Author Mary Jo Rogers, Ph.D. is a partner at Strategic Talent Solutions. She recently published the book, “Nuclear Energy Leadership: Lessons Learned from U.S. Operators,” by PennWell. maryjo@ strattalent.com.
  14. 14. For info. http://powereng.hotims.com RS#6
  15. 15. 12 www.power-eng.com The Fall of the F-Class Turbine Advanced class turbines such as the M501J are overtaking F-Class turbine technology as the preferred choice for new gas-fired projects.Photo courtesy:Mitsubishi Hitachi Power Systems Americas. BY MICHAEL J. DUCKER temperatures and pressure ratio. As advances were made in materials and cooling technologies, gas turbines were able to fire hotter, resulting in better efficiencies and higher outputs. Design changes in the compressor and tur- bine section were commonly needed, and thus when a manufacturer made improvements significant enough to increase output and efficiency, a new turbine class was born. Although at I t seems oil prices are not the only phenomenon experienc- ing a sudden, and seemingly unexpected, decline from the status quo. For the first time since F-Class turbine technology came to dominate the market over 20 years ago, the technology is no longer the leader in North America 60 Hz heavy duty gas turbine (HDGT) sales. Ad- vanced class turbine (typically defined as G-, H-, and J- class technologies) sales have seen greater than 50 per- cent year-on-year growth in the past five years and are the reason for this unseating. The recent gas turbine OEM emphasis on these advanced technolo- gies confirms the trend is here to stay. DEFINING THE CLASSES Historically, gas turbine frame types were defined by output, firing For the first time in over 20 years, F-Class turbine technology no longer commands majority share in the North America 60 Hz heavy duty gas turbine market Author Michael Ducker is the manager of Mar- ket Research at Mitsubishi Hitachi Power Systems Americas. In this role, Michael is responsible for strategic analysis of energy markets. GAS TURBINES
  16. 16. For info. http://powereng.hotims.com RS#7
  17. 17. 14 www.power-eng.com HDGT Market Share North Amreica Market Share Evolution between D/E-Class, F-Class, and G/H/J-Class Turbines. 1 D/E Class %ofGTsalesbetweenclasses 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% GT Sale Year 1980 1985 1990 1995 2000 2005 2010 Actual Trend G/H/J Class FClass Source: 2014 McCoy Power Report off, marking the beginning of the tran- sition away from F-class technology and into the new era where efficiency, not a turbine class or flexibility, is now king. WHY NOW? Just a few years ago, many gas turbine OEMs hyper-focused their marketing on the flexibility of F-class turbines. With increasing penetration of renew- ables – some studies even suggesting upwards of 80 percent renewables in the U.S. as technically achievable – it seemed as though F-class turbines would dominate the market and would help transition the U.S. to a new wave of renewable energy technologies. Yet in this same time frame, several events occurred helping to promote the up- ward trajectory of advanced class tur- bines. First, EPA regulations combined with low gas prices facilitated the clo- sure of thousands of megawatts of coal-fired generation. While this result was not at all unexpected, what was somewhat unexpected was how these units were replaced. Many early retire- ment forecasts pegged coal units with primarily the only large HDGT prod- ucts on the market. Yet in 1987, we see the introduction of F-class technology and a rapid rise of market shares as it simultaneously erodes D/E-class tur- bine sales. By 1996, F-class becomes the relative market leader and enjoyed nearly 20 years of sustained majori- ty market share. Yet in the late 1990s and early 2000s, the introduction of advanced class turbines begins to take times the nomenclature became murk- ier, as evidenced by technologies called “F-class” that featured firing tempera- ture, output, efficiency, and design in line with advanced technology, today’s HDGT classes can be broadly catego- rized into three areas based on OEM gas turbine product names, size, and efficiency. Focusing on size, D- and E- class engines are typically in the 75 – 110 MW range. Products include GE’s 7E.03, Siemens SGT6-2000E, and Mitsubishi Hitachi’s H-100. F-class tur- bines are typically in the 170-230 MW range. Products include GE’s 7F.03-.05 models, Siemen’s SGT6-5000F, and Mitsubishi Hitachi’s M501F. Lastly, the advanced class turbines (G-, H-, and J- frames) are typically in the 275 – 350 MW range. These include Mit- subishi Hitachi’s M501J and M501G machines, Siemens SGT6-8000H, and GE’s 7HA.01 and .02 models. A HISTORY LESSON Before considering where the mar- ket may be heading, it is worth taking a look at where we have been. Figure 1 shows a historical evolution of mar- ket shares between the HDGTs. Prior to 1987, D- and E-class engines were GAS TURBINES Past 5-Year Reliability/Availability Data (January 2010 - December 2014) Third Party Verifed Reliability and Availability Data Source: Source: ORAP® —All rights reserved. 2 100% 98% 96% 94% 92% 90% 88% 86% M501G F-Class -1.36% - 0.69% Reliability Availability Reliability/Availability% 99.05% 91.78% 97.69% 91.09%
  18. 18. Email: info@terrasource.com Web: www.terrasource.com/pe Truck Dumpers & Receiving Bunkers Positive Displacement Feeders Vibratory Feeders Crushers & Sizers Screening & Processing Conveying & Material Handling Storage & Reclaim Boiler Fuel Feed Systems for Coal and Biomass Power Material Handling & Size ReductionMaterial Handling & Size Reduction ffffffffffffooooooooooorrrrrrrrrrrr CCCCCCCCCCooooooooooaaaaaaaaaaaallllllllllll aaaaaaaaaaaannnnnnnnnnnddddddddddd BBBBBBBBBBBBiiiiiiiiioooooooooommmmmmmmmmmaaaaaaaaaaaasssssssssssssssssssssss PPPPPPPPPPPPoooooooooowwwwwwwwwwwweeeeeeeeeeeerrrrrrrrrrffff CCCCCC lll ddd BBBBBBiii PPPPPPfor Coal and Biomass Power CRUSH. FEED. PROCESS. CONVEY. STORE. TerraSource Global offers three market-leading brands of material handling and size reduction equipment to the power industry, whether it be for coal-fired power generation or 100% or co-firing of biomass and alternative energy fuels. Our Gundlach Crushers brand single- stage and two-stage double roll crushers crush coal at the mine mouth or preparation plant, or at coal-fired power stations. Our Jeffrey Rader brand material handling systems are used to unload, convey, screen and crush in the multiple stages of biomass energy generation, from truck/rail receiving through metered in-feed into the boiler. Our Pennsylvania Crusher brand impactors, granulators, hammermills, single roll crushers and sizers are found in 75% of all power plants processing coal in the USA and are used for multiple material reduction and processing applications in 79 countries worldwide. Additionally, Pennsylvania Crusher brand positive displacement feeders provide consistent, dust-free feeding of coal for improved plant safety. These three distinguished brands, recognized and trusted across the globe, are now available from a single source. Contact us today, visit our website or follow us on social media for additional information. Handling a World of Materials The brands comprising TerraSource Global (Gundlach Crushers, Jeffrey Rader and Pennsylvania Crusher) are wholly-owned subsidiaries of Hillenbrand, Inc. (NYSE: HI) © 2015 TerraSource Global. All Rights Reserved. BOOTH 417 Coal Handling & Storage Conference & Exhibition October 5-7, 2015 Hyatt Regency at the Arch St. Louis, MO For info. http://powereng.hotims.com RS#8
  19. 19. 16 www.power-eng.com Yet the regulatory permitting issue is unfortunate with the number of own- ers and developers who, in prior years, based air permits, certificates of public need, transmission interconnect studies, and the like on a smaller F-class tech- nology but viewed changing permits to advanced class turbines as too costly or, more importantly, a potential regulato- ry delay. When a permit is in hand, not many developers are eager to risk opening their projects to public or governmental change of hearts even if the economics make better sense. As more permits are initially filed to include advanced class technologies, it is likely this portion of the F-class market share will continue to deteriorate over time. Of course there are other strategic reasons a developer may choose F-class over advanced class turbines – such as parts pooling, desire for multi-unit configurations, mitigating regional re- quirements for loss-of-load contingen- cies, and other reasons not considered beyond maximum capacity needs or permitting issues. Still, the economics and competitiveness of advanced class turbines over F-class technologies are difficult to negate. THE DRIVE TOWARDS EFFICIENCY In 2011, Mitsubishi Hitachi Power Sys- tems (MHPS) demonstrated the J-class technology at its “T-Point” test facility in Takasago, Japan. 2,900°F turbine inlet temperature was achieved, translating into a combined cycle efficiency of 61.5 percent. Today, MHPS is poised to release additional improvements to its advanced class technologies capable of achieving >63 percent efficiency. General Electric markets its 7HA.02 capable of achiev- ing >61 percent efficiency and Siemens, though quiet recently, still maintains their SGT6-8000H at 60 percent efficien- cy. With natural gas prices continuing at record lows, will these major gains on efficiency still be realized in the market? order until system load is met. Therefore, competitiveness in deregulated power markets translates into being “1st on, last off” – meaning the most efficient units will be the first ones to power on (and be- gin earning profits) and the last ones to turn off (maximizing profits throughout operation). From the value chain of these markets, advanced class turbines are the clear winner and, subsequently, sales in these markets have reflected that. WHY F-CLASS STILL SELLS Some still consider F-class as the “proven” technology (i.e. less risky from a reliability standpoint) even though the new F-class engines of to- day have less operating hours than the G-class engines that have been run- ning since the late 1990s. Additional- ly, 3rd party gener- ator reliability and availability data clearly shows some of these advanced engines featuring steam cooling are ac- tually more reliable than their F-class counterparts (see Figure 2). Still, other themes emerge outside of the “proven” technology view- point. Primarily, two rational reasons come to light for a developer to choose F-class over advanced class technolo- gies: transmission issues that would require system upgrades to incorporate a larger unit, or the tragedy of regula- tory permits. Not much can or likely will change with the former. There will continue to be a market for D/E-class and F-class turbines to meet the needs of developers who have finite capacity needs. These include building a gas tur- bine in a region that does not require >500 MW capacity due to demand or building at a brownfield/other site that would require significant – and costly – transmission upgrades to enable the larger unit. low utilization rates as the most at risk to retire, and thus a 1:1 capacity re- placement would be unlikely. Yet what materialized are a number of the large advanced class turbines replacing these coal units that had minimal operating hours. Long-term resource planning hinges on having an adequate installed base to meet peak demand, and this motivated many owners to replace old- er under-utilized capacity with new, highly efficient baseload NGCC capac- ity that simultaneously displaced more costly generation on their system. Moreover, continued expansion of de- regulated energy markets and consolida- tion of balancing authorities in the US and Canada helps to improve region-wide load balancing. As a result, a highly inte- grated grid capable of pooling many re- sources with minor flexibility require- ments reduces the needs to procure sources with major flexibility capabilities. For instance, as PJM has grown, the entire regional trans- mission organization (RTO) now only typically procures 2,000 MW of primary reserve requirements for a market that sees peak loads in excess of 150,000 MW (<2 percent of total demand). These an- cillary services are pooled across the RTO and within regional subsets, not just via a few highly flexible units. Undoubtedly some markets need greater flexibility, but advanced class turbines are continuing to push the envelope in this area. Minimum emissions compliant loads and start times are now nearly equivalent between F-class and advanced class units. And thus if flexibility attributes between the gas turbine classes is es- sentially equivalent, what is valued in these markets? At their core, deregu- lated energy markets thrive on the eco- nomic dispatch principal whereby units are cost-effectively dispatched in merit GAS TURBINES “The economics and competitiveness of advanced class turbines over F-class technologies are diffcult to negate.”
  20. 20. ADVANCED CLASS TURBINES WILL CONTINUE TO LEAD Moving forward, there are many questions regarding centralized power generation and the role it will play in a future considered ripe for demand re- sponse, energy efficiency, and distrib- uted generation. Yet at least within the bulk power category, advanced class turbines are in a position to succeed and recent market events certainly sup- port this fact. The way any successful developer operates is simply to hedge risks against potential market out- comes. When one stacks up the potential and likely future market needs for cen- tralized power, it is hard to see F-class technology being a better hedge over the advanced class turbines. Meanwhile, President Obama’s proposed CO2 new source (NSPS) and existing source performance standards (ESPS) will no doubt have a profound effect on the drive towards better efficiency. The NSPS rules themselves are essentially an efficiency standard, whereby the more efficient the unit is the lower the lb-CO2/MWh emissions rates will be. The ESPS rules may further exacerbate coal retirements and give way to newer, more efficient advanced class gas turbines. Just the threat of CO2 taxes or a formal carbon trading scheme, even if assumed 10-15 years away, can still make a dent in a project’s proforma. While the regulations themselves will be contested, the general trends are driving towards a low-carbon regulatory and policy landscape. In North America, the future certainly seems promising for high efficiency gas turbines. Deregulated markets continue to expand, and with recent and new environmental regulations continuing to push coal out of the market, baseload gas generation is a nice fit. This trend is not unique just to the United States and Canada; Mexico’s recent market reforms are bolstering the need for more efficient and environmentally friendly gas-fired generation in lieu of existing coal assets. Additionally, as markets continue to move towards greater dependencies on gas-fired generation, gas units will evermore be competing amongst themselves to be the lowest cost energy producer. Efficiency will drive who outperforms who in the markets.
  21. 21. 18 www.power-eng.com MARKET ANALYSIS A New Era of Demand Response D emand Response (DR) capability in North America has grown considerablyinthepast five years, both at utili- ties and within competitive markets such as PJM. However, DR technologies and policies have generally relegated DR to a minor role as a last-called resource. DR has typically been slower to respond than combustion turbines, and the load relief it provides has been difficult to assess pre- cisely (if at all) in the real-time operating environment in which control center staff operate. Furthermore, regulatory policies in support of DR have generally focused on the magnitude of megawatts achieved at the expense of the quality and useful- ness of those megawatts. Slowly, but sure- ly, this is changing. The use of DR in grid planning and operations has solidified as utilities in- creasingly rely on DR to meet installed capacity requirements and sometimes even operating reserve requirements. Fur- thermore, independent system operators (ISOs) led by PJM have incorporated DR into procurement mechanisms for capaci- ty, energy, and ancillary services. Industry acceptance of DR as an integral part of the future grid continues to grow, with states like California and New York rolling out major regulatory initiatives and Hawaiian Electric issuing a request for proposals to Authors Stuart Schare is a Managing Director of Energy at Navigant Consulting Inc. Brett Feldman serves as Senior Research An- alyst at Navigant Consulting. Blurring the Lines between Generation and Demand-Side Resources BY STUART SCHARE AND BRETT FELDMAN
  22. 22. 316 SS Construction IP66/68 a better way to view LEVEL viewing angle 140° orioninstruments.com High-visibility level indicators and transmitters from Orion Instruments are custom-engineered and built tough for the most demanding applications. Contact us to find out how personnel safety, cost of ownership, and reliability can all be improved over traditional sight glass gauges. ORION For info. http://powereng.hotims.com RS#9
  23. 23. 20 www.power-eng.com MARKET ANALYSIS in electricity usage by end-use customers from their normal consumption patterns. What makes these consumption changes “demand response” is that they are in re- sponse to changes in the price of electrici- ty or to direct incentives, typically at times of high wholesale market prices or when system reliability is jeopardized. Common examples of DR include direct load control of residential air con- ditioning, curtailment of commercial cooling and lighting loads by building op- erators participating in utility programs, and shutdown or deferral of industrial/ manufacturing processes. An important distinction for DR is that it must be dis- patchable by a utility or system operator, or be initiated by a customer in response to a non-fixed price signal. Thus, static time-of-use rates and scheduled thermal energy storage are not typically consid- ered to be DR; but critical peak pricing— where the highest price tier is only in ef- fect periodically as called by the utility or operator—is characterized as DR. UTILITY PROGRAM OR GRID RESOURCE? DR has matured from manual response to inflexible, interruptible industrial rates of a generation ago to the much more automated and customizable programs and products being offered today—with plenty of everything in between account- ing for the bulk of current DR capacity in North America. An important distinction in characterizing DR activity is whether the curtailment capacity is part of a verti- cally integrated utility program or within a market defined by an independent sys- tem operator (ISO). Utility programs are typically based on a regulator-approved tariff, and offer a fixed incentive, or set of participation and incentive options, to eligible customers who voluntarily enroll in the programs. While voluntary, many programs have non-performance penalties or provisions for withholding incentives or removing customers from the programs. One of the most frequently used and long-standing programs is Florida Power & Light’s (FPL) On Call Savings Program with more than 800,000 participants and well over 1,000 MW of central air conditioning curtailment capability. Xcel Energy in Minnesota and Colorado has a similar participation rate of over 20 per- cent of eligible customers. Other non-ISO utilities with significant residential DR programs include Duke Energy Caroli- nas, NV Energy, and PacifiCorp. Most investor-owned utilities also offer one or more rates or programs for commercial/ industrial DR. DR programs tend to be more lim- ited in ability than generators in that they are often only available when cooling loads are prominent, and they are commonly restricted to perhaps a dozen events per year of four to six hours in duration, often within a nar- row window of eligible hours. DR IN ISO MARKETS In the United States and Canada, there are nine major Regional Transmission Or- ganizations (RTO) and ISOs responsible for running wholesale electricity markets DR aggregators for the provision of “grid services,” including ancillary services, from demand-side resources. So which technologies and policies will drive DR into the future as a more integrated and valued resource? This article describes the current DR landscape in North America, including state and regional activities that uniquely affect how much DR is in place and how it is utilized. It covers some of the emerging DR technologies that are allowing DR to be viewed more on par with generators, and it reviews new applications of DR that are raising its prominence as a valued re- source alternative for utilities and system operators. Looking ahead, emerging state policies and utility initiatives are driv- ing DR to a heightened prominence that would have been difficult to envision just five years ago. DR IN NORTH AMERICA Demand response is a term that can mean many different things to many dif- ferent people. A common definition that tracesbackatleasttoaU.S.Departmentof Energy report nearly 10 years ago charac- terizes DR as changes (usually reductions) North America RTO and ISO Map and Associated DR Capacity 1 ISO New England NewYork ISO Electric Reliability Council ofTexas California ISO Southwest Power Pool Midcontinent ISO Alberta Electric System Operator Ontario Independent Electricity System Operator PJM Interconnection 500 MW 1000 MW 1000 MW 3000 MW 2000 MW 10,000 MW
  24. 24. For info. http://powereng.hotims.com RS#10 Lapeyre Stair... We don’t miss a step. Lapeyre Stair serves all your stair needs quickly and precisely. In-house detailing and design ensure project accuracy – every time, on time. Choose from our expanding product line to meet your on-site assembly requirements. www.lapeyrestair.com Welded Egress Stairs • Alternating Tread Stairs • Platform Systems • Bolt-together StairsW lW lW lW ldeddeddedded Eg s Ss Ss Staitaitaitaitai • Alte m S BolBol thethethethether Sr Sr Sr Sr Staiting Tg Tg T d Stai • P• P• P• P• Platlatlatlatform Sm S Accurate and timely advanced stair building technology since 1981. Send us your plans or email us at ls.sales@lapeyrestair.com to learn how you can experience the ease of working with long-time stair building professionals. Or, to immediately consult a knowledgeable customer service agent, call 800-535-7631. 21www.power-eng.com Reforming the Energy Vision (REV), the initiative’s goal is to transform the cur- rent utility model into a distribution sys- tem platform (DSP). The role of the DSP would be to lay the groundwork required for energy service providers on both the grid side and the customer side of the meter to provide products and services 2014 Polar Vortex, most DR bid into PJM was only required to be available for ten six-hour events during summer months. Within the New York ISO footprint, the New York Public Service Commission is undertaking perhaps the most ambitious plan to date from a state looking to mod- ernize its electric utility sector. Called and managing a large transmission grid with high voltages. Some of these orga- nizations have crafted DR programs or integrated DR into their market designs, thereby encouraging customer load par- ticipation. DR has matured in the elec- tricity market and has been afforded the opportunity to bid directly against gen- eration in these markets—commonly for capacity, but also for energy and ancillary services in some regions. Currently, there are approximately 30,000 MW of DR in North America, according to Navigant Research’s recent Demand Response report, with a bit over half coming from the RTOs/ISOs. This is made up of about 8 million residential and commercial & industrial (C&I) cus- tomers. This market size equates to ap- proximately $1.5 billion in DR revenues for DR providers and customers. PJM manages the largest DR market in the world, at approximately 10,000 MW. In some zones within the ISO, DR makes up more than 10 percent of the capacity resource base. PJM has also been a leader in making it possible for DR to participate and submit bids for reductions in the syn- chronized reserves and frequency regu- lation markets. However, there are some headwindsthatmay challengethecontin- ued growth of DR in PJM markets, such as regulatory/legal challenges and increased operational requirements that limit com- pensation for DR that is not available 24 hours a day, year round. Until recently, punctuated by the grid demands of the “Looking Ahead, emerging state policies and utility initiatives are driving DR to a heightened prominence that would have been diffcult to envision just fve years ago.”
  25. 25. For info. http://powereng.hotims.com RS#11 Highly accurate and reliable flow measurement in extreme temperatures No process stops for installation Virtually maintenance free Decreased downtimes and forced outages The Ideal Solution for: Phase detection – steam or water in the HRSG during startup Controlling drain valves during heavy cycling Measurement of auxiliary liquid systems – water treatment, cooling tower flows, natural gas Non-Intrusive Flow Measurements in the HRSG Industry Toll free: 1 888 852 7473 www.flexim.com salesusHflexim.com FLEXIM AMERICAS Corporation www.power-eng.com MARKET ANALYSIS to enhance the distribution system’s ef- ficiency. Examples of these products and services include network sensors, dis- tribution automation, DR, distributed generation, and microgrids. As part of the proceeding, utilities are required to develop their own DR programs as a sup- plement to or replacement of the NYISO DR programs. In California, the ISO (CAISO) is one of several bodies contributing to a “bifur- cation” plan to split DR into supply-side and “load-modifying” resources. Essential- ly, this means is that price-based programs intended to shape loads will remain with the utilities, while programs focused on reliability, flexibility, and ancillary services will reside with CAI- SO. Furthermore, a stakeholder process is underway where all types of DR would be identified, as well as how they could play a part in California’s electrical grid and what ben- efits they could provide. State policy is directing utilities to consider DR, not just generation, as a partner in planning how to balance and ensure reliability for the electric grid. Further, the California PUC is leading a process to value different types of DR for its ability to contribute to reliability, as well as to support the state’s goals for reducing greenhouse gas (GHG) emissions. DR VENDORS AND SERVICE PROVIDERS As DR offerings and technologies have matured, an ecosystem of vendors has emerged with continually advanc- ing hardware, controls, and head-end communications systems. Similarly, load curtailment “aggregators” have formed to recruit and enable custom- ers to collectively deliver to utilities and ISOs DR capacity measured in the tens or hundreds of megawatts—or even more in some ISO markets. The DR market can be segmented from a vendor/aggregator perspective. On the C&I side, companies such as EnerNOC, CPower, and Johnson Controls special- ize in one or more DR-related services including recruiting customers, automat- ing rapid and reliable load response, and providing granular building usage data and performance diag- nostics. The bulk of the mass-market segment includes single-fami- ly homes with central air conditioning and/ or electric water heat- ing, as well as small businesses with pack- aged units of 20 tons or less. As load control switches are nearly a commodity, and com- municating “smart” thermostats are fast becoming the specialty domain of Nest and a variety of established and start-up companies, players in the mass market segment such as Comverge and Eaton (formerly Cooper Power Systems) special- ize in one or more of the following: mar- keting/customer acquisition, head-end control systems, and communications be- tween the customer and the service pro- vider/utility (for example, Eaton offers a two-way mesh network dedicated to load control). A few vendors attempt to service all markets in the DR space. Honeywell is probably the best established, leveraging its experience in commercial building management as well as its thermostat hardware business and its 2010 acquisi- tion of Akuacom, an early developer of open source Auto-DR software on the OpenADR platform. Other major players include Schneider Electric and Siemens, global companies attempting to develop differentiated services and acquire market “State policies provide one indication of the future of DR, and these suggest a more integrated role for DR in resource planning and grid management.”
  26. 26. For info. http://powereng.hotims.com RS#12 For info. http://powereng.hotims.com RS#13 www.power-eng.com Fastest Biodegradable Descaler Yet! Goodway ScaleBreakÆ recaptures TIP THE SCALE IN YOUR DIRECTION. BEFORE AFTER CALL 888-364-7749 www.goodway.com share from those who have focused lon- ger on the DR market. DR AS A GRID MANAGEMENT RESOURCE If DR is now well-established as a ca- pacity resource that can provide emer- gency relief for reliability purposes, it has only recently begun making a name for itself as an operating resource to be used on a more regular basis for providing 10-minute operating reserves and other more precise ancillary services. Many of the core attributes describ- ing combustion turbines and other generators have analogs for DR re- sources. For example, both generators and DR can be characterized by their megawatts of capacity and by the time it takes to bring those megawatts onto the grid. The real question is whether the per- formance of DR is comparable to gen- eration—or at least whether DR can perform well enough compete and to provide a portion of the services re- quired by grid operators. DR has been active in the synchro- nous reserves market in PJM for several years, providing up to 25% of the re- quirement at times. However, chang- es to the transmission system in 2013 dramatically lowered prices in this market and made it uneconomic for a lot of the DR to participate. These conditions may change in the future, so the technical capability is ready to jump in when prices warrant it. The frequency regulation market has shown signs of growth, particularly since PJM implemented FERC Order 755 which affords greater compensation to faster-responding resources. Several alternative resource providers, including batteries and DR, have begun bidding into the market and showing their ability to compete. A major driver for DR is the increasing penetration of intermittent renewable energy due to both regulatory mandates
  27. 27. 24 www.power-eng.com MARKET ANALYSIS of the generation portfolio. The state will experience steeply declining net loads (customer demand minus cus- tomer-sited renewable generation) in the mid-to-late morning as solar pro- duction picks up, and even more dra- matic increases in net load growth in the late afternoon as solar production drops off concurrent with an increase in residential loads. The new load shape provides op- portunities for DR (as well as storage), especially in the late afternoons when load curtailment could slow—or at least help manage—the sharp ramp up. Alternatively, DR could be used to shave off some of the new evening peak. In the mornings when net load is in decline, DR can also help to balance the grid by soaking up excess supply as generators struggle to ramp down. Re- call that DR is defined as “changes” in usage by end-use customers, but these changes don’t always have to be reduc- tions. An increase in demand—in response to an incentive or price signal—is also demand response. Some of the ap- plications and technologies for DR as a down-ramping resource include over-cooling cold storage facilities and refrigerated warehouses, within ac- ceptable limits of course. Essentially, the customers are using existing facilities and technologies for on-demand thermal storage. In this case, the benefit may be the ability to draw power from the grid, as well as the ability to tap into the stored energy at a later time to reduce demand from the grid.A newer and more innovative application of customer-sited thermal storage is grid-interactive water heat- ing (GIWH). GIWH is the emerging consensus term for describing electric water heaters controlled by real-time, two-way communication with the util- ity, grid operator, or load aggregator. When equipped with grid-interac- tive controls, an electric water heater and improving economic and regulatory treatment of renewables. Resources like solar and wind pow- er rely on natural elements that can sometimes be unpredictable and re- quire backup power resources to re- spond quickly if clouds roll in or the wind stops blowing. Traditionally, this has been accom- plished by having fossil power plants on standby or generating at below op- timal levels. As the penetration of intermittent renewables increases, however, build- ing generation just for this purpose may kill the business case for the re- newable energy, so cheaper, more flex- ible backup alternatives must be con- sidered. DR can help fill this void. California is perhaps the poster child for renewable energy inputs un- settling a grid. In 2013, CAISO con- structed the now famous “duck chart,” which shows the anticipated future load shape for the state in the shoulder seasons as solar becomes a larger part Source: Attribute DR Resources Generation Resources Resource Size Number and size of customers; curtailable share of total load MW unit size Responsiveness Advanced notifcation requirements Start-up/ramp-up times Reliability Communications reliability & variance in customer load response Availability of fuel supply & transmission capacity Limitations Constraints on number and duration of events Emissions limits Temperature Dependency Temperature-dependent loads; hourly/seasonal variations Temperature-dependent heat rates and capacity Resource Diversifcation Diversity of self-generation, customer sectors,and participating end-uses Fuel diversity and baseload vs.peaking AnalogousAttributes between DR and Generation Resources California’s Future Load Shape and Opportunities for DR 2 Increase in load could allow generators time to ramp down Overgeneration risk Reductions in load could allow generators time to ramp up or shave off the new evening peak 2012 (actual) 2013 (actual) Ramp need ~13,000 MW in three hours 28,000 26,000 24,000 22,000 20,000 18,000 16,000 14,000 12,000 10,000 0 Megawatts Hour Net load – March 31 12am 3am 6am 9am 12pm 3pm 6pm 9pm 2014 2015 2016 2017 2020 2018 2019
  28. 28. 25www.power-eng.com For info. http://powereng.hotims.com RS#14 can respond to near real-time input by enabling fast up and down regulation and frequency control for the purpose of providing ancillary services and renewable storage to the utility or grid-operator. In addition to two way communication, GIHWs can measure and transmit information on water tem- perature, so grid operators know how much energy storage potential the fleet of GIWHs have at any given time; and based on customer usage patterns, they also can judge how much load curtailment, or regulation down service, the fleet can provide while still meeting customers’ needs. Through the use of high-storage capacity, highly in- sulated water heater tanks, GIWH can provide even greater storage and operational capacity/flexibility than traditional water heaters that are simply retrofit- ted with interactive controls. THE FUTURE OF DR IN NORTH AMERICA If DR is on a decades-long evolutionary path, will it continue to mature into an even more valuable grid re- source on par with generation? Or will energy storage and the increasing demands for grid management in a world of high renewables penetrations squeeze DR out of the picture? State policies provide one indication of the future of DR, and these suggest a more integrated role for DR in resource planning and grid management—but with stricter requirements on how DR must perform. The days of rarely called interruptible rates and monthly capacity payments for the occasional 3-hour event may be in the past. The advent of grid modernization is tied to the new resiliency view on how the grid should be designed. States like California, Illinois, Maryland, New York, Massachusetts, and Hawaii have begun grid moderniza- tion proceedings to investigate how the future grid should look in terms of issues including metering and dynamic rates, distributed generation, and the associated implica- tions transmission and distribution infrastructure. This modernization approach goes beyond siloed hearings on the individual aspects of utility operations to create a holistic structure for grid planning and payment formulas. DR may finally be able to compete on a level playing field, which could eliminate some current forms of DR while encouraging development of others. At the national level, a current FERC Supreme Court case has much bearing on the ability of DR to partici- pate in wholesale markets in the United States. In ear- ly 2011, the FERC issued Order 745, which required
  29. 29. 26 www.power-eng.com MARKET ANALYSIS This change encompasses a diverse suite of technologies that includes en- ergy storage, energy efficiency, DR, and the advanced software and hardware that enable greater control and interop- erability across heterogeneous grid ele- ments. These are all key components of the emerging energy cloud that is be- ing accelerated by evolving regulation of carbon emissions, a more proactive consumer or pro- sumer, and the con- tinuously improving financial viability of distributed resources compared to tradi- tional generation. Navigant projects that there will be about 70,000 MW of DR in North America by 2023, an 11 percent annual growth rate. One indi- cation of the growing prominence of DR and the vendors/service providers supporting it is the growth in membership of the leading DR trade association. The Peak Load Manage- ment Alliance (PLMA) has been in existence since 1999, yet just in the past three years had more than dou- bled in membership from less than 40 members to nearly 90 today. The recent setbacks and regulatory uncertainty in PJM—while interrupting DR’s long-term trajectory— are an indication that the industry demands more re- sponsiveness and account- ability from DR resources. This will push the continued evolution to more fully auto- mated, fast-responding, and controlla- ble DR resources that are able to play an increasing role in integrating inter- mittent renewable energy and in man- aging real-time grid operations. wholesale energy markets to pay the same for DR as they do for electricity generation. Energy supplier and gen- eration groups challenged the order in federal courts as unjust and unreason- able compensation. In May 2014, a panel of the U.S. Court of Appeals overturned the or- der by a 2-1 vote, potentially reverting things to how they were before—or making them worse, depending on interpretation. The majority opinion went even further and found that DR in the wholesale energy market is a re- tail transaction, which is outside of the FERC’s jurisdiction. In December 2014, FERC asked the U.S. Supreme Court to review the case, which was granted, setting the stage for a hearing likely in early 2016. If the worst-case scenario plays out and DR is disallowed from all wholesale markets, states and utilities will have to fill the void. Depending on their status and disposition, this could take months to several years to enact. The short-term momentum of DR would be halted, but in the long term, if states and utilities assign higher value to DR than do the wholesale markets, it could lead to in- creased opportunities for DR. DR IN THE ENERGY CLOUD Aside from government policy, the power sector is undergoing a fundamen- tal transformation that could lead to an increase in DR capacity or how widely DR is used. Led by rooftop so- lar, encouraged by the prospect of cheap storage, and with the possibility of massive amounts of electric vehicles on the grid, the industry is slowly shifting away from a centralized hub-and- spoke grid architecture based on large centralized generation assets like fossil fuel, hydro, or nuclear power plants. The new paradigm—dubbed the En- ergy Cloud in a 2015 Navigant white paper—envisions an increasingly de- centralized electrical grid that makes greater use of distributed energy re- sources, including DR. “Navigant projects that there will be about 70,000 MW of DR in North America by 2023, an 11 percent annual growth rate.” “Smart”thermostats are fast becoming the specialty domain of several established startup companies,as demand response (DR) becomes a major resource for power producers.In some places,DR developers are granted the opportunity to bid directly against generation.
  30. 30. For info. http://powereng.hotims.com RS#15
  31. 31. 28 www.power-eng.com A large Hyundai shovel operates on the surface of cured dense slurry at the Matra power facility’s impoundment in Hungary,attesting to the compressional strength and environmental stability of the end-product.The shovel excavates cured slurry from around the perimeter for use in building up the levee of the 15-tiered,150-foot-high impoundment.Photo courtesy:NAES ENVIRONMENTAL REGULATION
  32. 32. 29www.power-eng.com BY DALE TIMMONS T he Environmental Protec- tion Agency’s (EPA) newly enacted Coal Combustion Residuals (CCR) rules and proposed Effluent Limita- tions Guidelines (ELG) will significantly impact waste management practices in the coal-fired power industry. The new rules will regulate fly ash settling ponds out of existence; regulate the location, de- sign, operation, and closure requirements for impoundments; and impose new re- quirements for wastewater. Traditional “dry ash” management techniques satisfy the rules’ proposed re- quirements, but they suffer from inherent technical deficiencies and pose prohibi- tive costs. The Circumix™ Dense Slurry System (DSS) technology, developed by GEA EGI Ltd. of Hungary and represented ex- clusively by NAES Corporation in North America, mixes wastewater with CCRs to produce a stable product with near-stoi- chiometric use of water. Once cured, the slurry exhibits low hydraulic conduc- tivity, high compressional strength, no discharge of fly ash transport water, little or no fugitive emissions, and enhanced metals sequestration, thereby achieving the goals of the CCR and ELG rules. The EPA has also imposed stricter stan- dards for air emissions with the Mercury and Air Toxics Standards (MATS). As with the proposed CCR and ELG rules, the vast majority of toxic metals targeted by MATS originate from coal-fired power plants. The EPA recognized that many processes designed to remove metals from gaseous emissions result in a transfer of the metals to other effluents, which is one reason it Author Dale Timmons is a egistered geologist and Business Development Program Manager with NAES Corporation. Dense Slurry Coal Ash Management: Full Compliance, Lower Cost, Less Risk
  33. 33. Electron Microprobe Image of a No-Lime Sample 1 Source:NAES Corporation 30 www.power-eng.com fly ash transport water discharge, little or no fugitive dust, and enhanced se- questration of contained metals. These properties meet the performance re- quirements specified in the new CCR rule and the proposed ELG. DSS is currently used at eight power plants – seven of them in Europe and one in the U.S. Two more plants are being built or commissioned – one in Europe and one in India – that will use the technology. Circumix DSS systems have processed over 60 million cubic yards of dense slurry into environmen- tally stable end products, primarily using flue gas desulfurization (FGD) water and other plant wastewater as the stabilizing medium. In addition to achieving compliance with the new ELG and CCR rules, DSS offers numerous additional advantages: • Combined stabilization of ash and wastewater • Reduction of water use by 80 to 90 percent compared to traditional practice • Zero discharge of transport water • Significant reduction of plant-wide wastewater of trucks and heavy equipment signifi- cantly increases safety risks. DENSE SLURRY SYSTEM ASH MANAGEMENT A dense slurry system (DSS) offers a safer, less expensive alternative to dry ash management while producing a product with improved environmental perfor- mance. DSS is a high-intensity mixing process that combines plant wastewater with CCRs to produce dense slurry that is easily pumped to an impoundment or landfill. The process maximizes the avail- ability of reactive ions in the ash and opti- mizes the use of wastewater. Dense slurry produced by the DSS process displays a consistency of 50 to 60 percent solids by weight with a density of about 1.3 g/cm3 , which is maintained to within 1 percent. This is thick enough to minimize free water but thin enough to allow pumping to a distance of over 6 miles using centrifugal pumps. Once discharged, the slurry hard- ens in 24 to 72 hours and substantial- ly cures in about a month. The cured product exhibits low hydraulic conduc- tivity, high compressional strength, no proposed the ELG rule. Suffice it to say, the CCR, MATS, and proposed ELG rules are requiring own- ers and operators of coal-fired power plants in the U.S. to make pivotal de- cisions regarding future operations at these plants and how best to address the regulatory changes. DRY ASH MANAGEMENT Power plants face a number of chal- lenges when converting to an alterna- tive ash management system because few options are available. Conventional practice is commonly called “dry ash” management, which is misleading. So- called dry ash management for transport and disposal to an impoundment or landfill typically involves the addition of 20 to 25 percent water to suppress dust. Once the wetted ash is transported and disposed of, it is typically spread and compacted using heavy equipment. Ad- ditional water is often added using sprin- klers or water trucks to control dust and improve compaction. Traditional dry ash management typ- ically involves handling and moving the ash multiple times, with each transfer adding more risk of dust release. To ad- dress this, the new CCR rules impose stringent controls on fugitive dust at im- poundments. Even after ash is spread and compacted, it can easily be mobilized by wind if allowed to dry. It also exhib- its relatively high hydraulic conductivity, which translates into high rates of leach- ate production. Traditional dry ash management also poses a major expense. The costs of transferring the ash to ash/water mixing facilities, together with the capital and operating costs of the facilities them- selves, are high. Truck transport, road construction and maintenance, fuel management, heavy equipment opera- tion and maintenance, continual dust suppression, lighting and security at the disposal site, plus associated labor fur- ther reduce the appeal of dry ash han- dling. Lastly, the continual operation ENVIRONMENTAL REGULATION
  34. 34. Electron Microprobe Image of a Lime-Added Sample 2 Source:NAES Corporation 31www.power-eng.com concrete contains about 25 percent bound water.) Although DSS has been used extensive- lyinEuropeandatoneplantintheUnited States for decades, plant-specific testing is still required to establish the proper blend of solid waste products and wastewater for optimal environmental performance. While performance-enhancing additives are available, all of the DSS facilities cur- rently in operation process ash that is suf- ficiently reactive on its own. The ash produced by some power plants in the United States, however, ex- hibits little or no reactivity. Where this is the case, additives may be used to in- crease compressional strength and reduce hydraulic conductivity. Typically, 2 to 3 percent active lime is enough to achieve adequate solidification. CASE STUDY: PRB COAL ASH For example, NAES tested samples of Powder River Basin (PRB) coal ash to determine their performance relative to DSS. The samples contained over 20 per- cent CaO, but only 0.14 percent of it was chemically active. Figure 1 shows an electron microprobe image of cured slurry product made using 60 percent PRB fly ash and 40 percent water. (Note the regions where ettringite crystals have formed.) After six weeks of curing, the low reactivity of the ash result- ed in very little cementation. The cured product exhibits a porosity of about 50 percent, as evidenced by the dark regions of empty space in the image. After curing, the sample showed com- pressional strength of 48,263 Nm-2 (7 psi) and the hydraulic conductivity measured 3 x 10-5 cm/sec. To find out how the PRB slurry per- formance could be improved, NAES pre- pared another sample – this time using 50 percent fly ash, 2.5 percent active lime, and 47.5 percent water by weight – and allowed it to cure for six weeks. In figure 2, the cured product shows a significant reduction in porosity compared to the variations in the amount of water used to make the slurry can impact process- ing parameters of that slurry. It has also demonstrated that small quantities of ad- ditives, where indicated, can dramatically improve product performance. The compressional strength and hy- draulic conductivity of cured DSS prod- ucts depend largely on the chemical reactivity of the fly ash contained in the slurry. This reactivity in turn depends on several variables: type of fuel, emission controls used, type of boiler, and combus- tion temperature, among others. As dense slurry cures, hydrated mineral crystals grow in the spaces between ash particles, including the following: Ettringite 60% Bound Water Allite 32% Bound Water This interstitial crystal growth se- questers water, entrains small parti- cles, and inhibits fluid flow. In addi- tion, the crystals act as an adhesive that binds ash particles together, resulting in greater compressional strength. This process – the same that occurs in the curing of concrete – is a desired outcome of DSS. (For reference, most • Low hydraulic conductivity (10-6 to 10-10 cm/sec) • High compressional strength • Enhanced metals sequestration • No risk of liquefaction or spills asso- ciated with liquefaction • Significant reduction of leachate vol- ume • Significant reduction of fugitive dust emissions • Enhanced land-use efficiencies from elevated disposal facilities • Reduced energy consumption Several variables contribute to low hy- draulic conductivities in the cured prod- uct, including particle size distribution, particle shape, water chemistry, and ash chemistry. The mixing process results in close packing of the ash particles upon discharge. The chemistry of the ash and water determine the type of crystal growth that takes place in the interstitial spaces between ash particles upon curing. PERFORMANCE ENHANCEMENT OF SLURRY PRODUCTS NAES has found in recent testing that
  35. 35. Hydration Curves Showing Sequestration ofWater OverTime 3 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0 5 10 15 20 25 30 35 40 45 50 0% CaO 2,5% CaO 5% CaO 10% CaO Free water (kg free water/kg total process water) Number of days of curing Freewaterpercentage 32 www.power-eng.com by progressively reducing hydraulic conductivity and increasing compres- sional strength. In active impoundments and land- fills that receive dense slurry, evapo- ration removes significant quantities of water before it can infiltrate the im- poundment. The hydration reactions that occur during curing, coupled with evaporation, result in zero discharge of fly ash transport water. A COMMERCIALLY OPERATING DSS IMPOUNDMENT IN HUNGARY The active ash disposal impoundment at the Matra Plant, which began opera- tion in 1998, consists of 15 tiers, each 10 feet thick, of solidified Type F ash that has been pumped to the impoundment from the plant as dense slurry. The 150-foot high impoundment covers an area of 314 acres at its base and 122 acres at the top. The established tiers have been planted with fruit trees. The top of the impoundment is di- vided into six smaller enclosures sep- arated by dikes. When an enclosure is full, discharge is transferred to an adjacent enclosure. Cured dense slur- ry from the perimeter of the full im- poundment is then excavated and used to construct the dike for the next tier. To prevent interruptions in plant operations caused by lack of dispos- al space, at least two of the multiple smaller impoundments at the top of the facility are always made available to receive dense slurry. The impound- ment poses no risk of liquefaction of ash products or catastrophic failure (e.g., inundation of the surrounding community) because the compres- sional strength of the contents ranges from 5,000 to 11,000 lbs/ft2 . Hence, there have been no slope failures or other incidents requiring remedi- al action since operations began. All leachate is returned to the plant for use in DSS processing, making this a amount of water sequestered with the concentration of lime. The samples were molded into 4-inch plastic tubes wrapped with geo- textile fabric at the base to allow leach- ate to drain out of the slurry. The cap- tured leachate was periodically poured back through the curing product. The samples and drained water were main- tained in a closed system to prevent evaporation of water. As shown in the hydration curves for the four mixes (Figure 3), water is rap- idly sequestered during curing. The mix with 2.5 percent active lime sequestered 90 percent of the free water in 15 days. Samples with higher active-lime concen- trations sequestered the same amount of water in five days or less. NAES also found that as the thick- ness of accumulated slurry product in- creases in an impoundment or landfill, so does the amount of water seques- tered. As dense slurry impoundments accumulate more slurry, the amount of leachate produced thus declines over time because the water that infiltrates has more time to react as it percolates through the curing product. These con- tinuing reactions enhance the perfor- mance of the impoundment over time no-lime sample – about 6 percent po- rosity in the lime-added product versus 50 percent in the no-lime product. The reduction in hydraulic conductivity of the lime-added sample – 3.4 x 10-6 – rep- resents about one order of magnitude. The compressional strength increased by 97 percent to 1,296,214 Nm-2 (188 psi). SEQUESTRATION OF WATER Mineral growth that takes place during curing sequesters significant quantities of water. This is important because the EPA’s preferred options under the proposed ELG prohibits discharge of fly ash trans- port water under any circumstance. Dis- posal facilities that use the DSS process have achieved zero discharge of transport water by reprocessing leachate to produce more dense slurry. To assess how much water is seques- tered in the DSS curing process, NAES tested ash samples from the Matra Pow- er Plant near Budapest, Hungary, the ‘flagship’ of DSS facilities. Using a slur- ry of 60 percent fly ash and 40 percent water by weight, NAES prepared sam- ples with 2.5, 5, and 10 percent active lime added, as well as a control sample without added lime, to correlate the ENVIRONMENTAL REGULATION
  36. 36. 33www.power-eng.com For info. http://powereng.hotims.com RS#16 Vacuum Systems by Busch Power up with custom vacuum system solutions by Busch Busch liquid ring solutions offer: Rugged reliability Single- and two-stage options Variety of materials of construction Meet all HEI standards ‘recipe’ for stabilizing CCRs. NAES conducted testing at numerous loca- tions using a pilot-scale dense slurry processing system. Prior to the pilot test, samples of combustion products and wastewater are analyzed to determine their chem- istry and particle size distribution. zero-discharge facility for both trans- port water and leachate. DSS TESTING The physical and chemical proper- ties of ash and water vary from plant to plant, so these materials must be tested at each site to determine the best The tiered and elevated DSS impoundment at Matra Power Plant in Hungary is planted with fruit trees.Inset: The cured dense slurry from the impoundment perimeter is used to construct a dike for newly discharged slurry on the top level.Photo courtesy:NAES The pilot-scale system is then used to process a range of promising ‘recipes.’ Each recipe is allowed to cure for 90 days before the samples are collected for testing. Data collected during slurry pro- cessing includes rheology parameters (yield stress and rigidity), water con- tent/flow dynamics, energy consump- tion, mix ratios, and water stoichiome- try. Cured samples may be analyzed for the following: • Compressional strength • Porosity and hydraulic conductivity • Bulk chemistry • Moisture and density • Electron microprobe analysis • Leach performance
  37. 37. WEBCAST REGISTER TODAY THE TOTAL CONDENSER PERFORMANCE WORKSHOP™: NON-DESTRUCTIVE TESTING SEPTEMBER 1, 2015 | 2:00PM CDT For info. http://powereng.hotims.com RS#17 produce the dense slurry • Zero discharge of transport water • Zero discharge of leachate if re- used for dense slurry production • Enhanced sequestration of con- tained metals • Reduced risk of groundwater con- tamination • Reduced or eliminated risk of dust generation • High compressional strength In addition, the tiered, elevated disposal facilities typically used with DSS enable more efficient use of dis- posal space. Piping the slurry to these impoundments reduces or eliminates the use of heavy equipment and its attendant safety and environmental risks. More to the point, DSS process- ing eliminates ash sludge liquefaction, and with it the risk of dike failure and catastrophic releases. The data collected, along with plant information, are used to determine system capacity, slurry pumping re- quirements, and impoundment/land- fill design. They are also used to esti- mate probable leachate production and environmental performance of the sta- bilized product. ENVIRONMENTAL PERFORMANCE The CCR and ELG rules are closely related and interdependent. Design changes at coal-fired power plants that affect the quantity and chemistry of generated wastewater also affect the transportation, management, com- position, beneficial reuse options, and disposal of combustion products. These changes in turn affect the design, operations, monitoring, and closure requirements for impoundments into which CCRs are deposited. They also influence decisions regarding the man- agement and fate of CCRs in existing impoundments. In terms of environmental protec- tion, operational safety, and financial risk, DSS has proven itself altogether superior to “dry ash” management. It not only meets the requirements of CCR and ELG but yields a product with outstanding environmental perfor- mance: • Hydraulic conductivity that is sub- stantially lower than that resulting from traditional “dry ash” man- agement as described in the pro- posed ELG • 80-90 percent less consumption of water compared to traditional ash sluicing • Stabilization of wastewater (in- cluding FGD water) used to ENVIRONMENTAL REGULATION
  38. 38. For info. http://powereng.hotims.com RS#18
  39. 39. 36 www.power-eng.com Valves & ActuatorsBY RUSSELL RAY, CHIEF EDITOR unchanged, innovative applications and design modifications are being developed to withstand these demand- ing environments. In addition, these improvements can reduce costs by sup- porting the control valve’s ability to throttle accurately, thereby providing better performance for high-pressure steam bypass, turbine bypass and oth- er critical power plant operations. Actuators regulate mass and energy flows by adjusting valves, flaps and cocks. The actuator and valve create a single unit — the control valve. Actuators perform different motion sequences, including linear, pivoting and rotating motions, and they are powered by pneumatic, hydraulic or electrical energy. Actuators receive a control signal from automation systems. The signal is converted into a motion so that the A single power plant uses hundreds of valves to control almost every as- pect of its operation. Valves, in conjunction with a con- trolling actuator, are used for pollu- tion control, feed water, cooling water, chemical treatment, bottom ash and steam turbine control systems. They work in harsh environments and are exposed to a variety of chem- icals, abrasive materials and high temperatures. They are critical in optimizing efficiency, and they are often the final control element in the operation of a power plant. What’s more, additional demands are being placed on valves and actu- ators as power plants are forced to be more flexible to accommodate the growth of intermittent sources of re- newable power and mandates to curb carbon emissions. As a result, valves and actuators must operate at higher pressures, temperatures and frequency. Although the basic technology for most valves and actuators has remained Cycle Isolation testing utilizes acoustic monitor- ing instruments to help customers monitor valve performance.Photo courtesy:ValvTechnologies OPERATIONS & MAINTENANCE
  40. 40. You know that Magnetrol® liquid level switches work hard for decades of accurate and reliable level detection. After all, that’s why you trust your operation’s safety and performance to them every day. So to honor the hardest-working, longest-lasting level switches still in operation, we want to hear your story. Tell us about your switch at justcantstop.magnetrol.com for a chance to WIN $500 and let MAGNETROL toughness pay off for you again. The hardest working buoyancy switch has already won your loyalty. Now let it win you some cash. magnetrol.com • 1-630-969-4000 • info@magnetrol.com © 2015 Magnetrol International, Incorporated For info. http://powereng.hotims.com RS#19
  41. 41. 38 www.power-eng.com acts as a piston to create linear force to close and open the valve. Power plants have traditionally used pneumatic actuators to drive the many control valves throughout their facilities. However, major improvements in control element of the actuating el- ement assumes a corresponding po- sition. With control valves, this is a stroke motion. With flaps, ball cocks or rotary plug valves, this is a pivoting motion. VALVE-ACTUATOR TYPES There are three common types of actuators: Electric, pneumatic, and hy- draulic. Pneumatic valve actuators are pow- ered with air or gas. The air pressure The Rotork CVA offers an accurate and responsive method of automating control valves without the complexity and cost of a pneumatic supply.Photo courtesy:Rotork OPERATIONS & MAINTENANCE
  42. 42. 39www.power-eng.com For info. http://powereng.hotims.com RS#20 www.cd-adapco.com info@cd-adapco.com COMBUSTORSGAS TURBINES GENERATORSCOMPRESSORS HEAT EXCHANGERSPUMPS DISCOVER BETTER DESIGNS. FASTER. MULTIDISCIPLINARY SIMULATION FOR CLEAN, EFFICIENT ENERGY AND ECONOMICAL, RELIABLE POWER VISIT US AT PUMP & TURBOMACHINERY SYMPOSIA AT BOOTH 1529/1531 position transmitter is greater than 300:1 position turndown. The valve body is coupled to an actu- ator assembly that contains a fail-safe spring to quickly close the valve, halt- ing fuel flow in the event of a power failure or turbine trip condition.  When electric control-valve actuator technol- ogy are helping power producers lower costs and boost efficiency. Valve actua- tors powered by an electric motor can withstand the demands of continuous movement. In addition, they work ef- fectively in harsh environments, and provide superior performance in a wide range of applications. The bene- fits include better efficiency, less main- tenance and enhanced performance of the control valves. What’s more, electric actuators do not require recali- bration over time. Once calibrated, the electric control valve actuator can op- erate for months, even years, without adjustment. Hydraulic actuators, which use pres- surized hydraulic fluid to open and close valves, are increasingly popular because of their ability to achieve high torque. Hydraulic actuators are de- signed to carry out linear movement of all kinds. When a large amount of force is required to operate a valve, hydraulic actuators are normally used. The most common type of hydraulic actuator uses pistons that slide up and down within a cylinder containing hydraulic oil and a spring. Young & Franklin offers electrome- chanically actuated (EMA) gas control valves designed specifically for the challenging operating conditions of in- dustrial gas turbines. Industrial gas turbines require pre- cise control of the combustion process to drive efficiency, reduce emissions, and maximize availability. According to Young & Franklin, the company’s EMA valves offer substantial advan- tages over their hydraulically actuated counterparts. Young & Franklin 3010 Series Choked flow valves are electromechan- ically actuated (EMA), single seat pre- cision fuel control valves. These sonic flow valves are available in a range of sizes suitable for industrial or power turbines of any size. The Y&F 3010 EMA gas control valve (GCV) is a modern, high precision control valve with excellent speed and valve position accuracy at low open- ings. This GCV electronically re-ze- ros its closed position reference every time the power is cycled and the valve