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2015 11 12 Cogeneration & On-Site Power Production

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2015 11 12 Cogeneration & On-Site Power Production

  2. 2. For more information, enter 1 at COSPP.hotims.com
  3. 3. www.scania.com THE SCANIA GENSETS. REDEFINING RELIABILITY. Whatever your challenge, the Scania Gensets will deliver everything that the Scania brand stands for in terms of sustainability, operating economy, fuel effciency, uptime and proven reliability. This is why the Scania Gensets are the given choice for demanding duties. Just plug in and relax. The Scania Gensets and Scania Services – a complete range of power generation equipment and services for maximum uptime and long-term profitability. Plug in and relax. For more information, enter 2 at COSPP.hotims.com
  4. 4. Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com2 November - December 2015 WHY DEPLOYMENT OF MICROGRIDS IN GRID-CONNECTEDAREAS ISA GROWINGTREND ■ HOW MECHANICALVAPOUR RECOMPRESSION CAN IMPROVE EFFICIENCY AND HELP INTEGRATE RENEWABLES ■ HELPING COMBINED HEAT AND POWER PLANTS PLAY A ROLE IN GRID BALANCING ■ THE DOS AND DON’TS OF MAINTENANCE FOR STANDBY POWER EQUIPMENT ■ CONDITION MONITORING WITH DATA-BASED PROGNOSTIC TECHNOLOGY ■ HOW FAST-TRACK POWER CAN CREATE A BRIDGE TO ECONOMIC DEVELOPMENT ■ THE LATEST ADVANCES IN PACKAGED CHP DESIGN AND TECHNOLOGY Distributed energy’s American opportunity 18 Volume 16 • Number 6 November - December 2015Contents Features 8 America’s distributed energy opportunity Why forthcoming US federal regulations on emissions reduction are generally positive for distributed energy, but have also created uncertainty within the industry. By Craig Howie 14 Microgrids: more than remote power To ensure continuity of power supply and protect against grid faults and emergency situations,‘grid-connected’ microgrids are growing in popularity. By Celine Mahieux and Alexandre Oudalov 18 Advantages of mechanical vapour recompression How mechanical vapour recompression (MVR) can improve energy efficiency in process plants and offer possibilities for integrating renewable electricity and demand side management. By Egbert Klop 22 CHP’s grid balancing capability Energy management solutions can result in more economic CHP plant operation and allow plants to participate in the smarter business of balancing the grid. By Juha-Pekka Jalkanen 26 Intelligent maintenance with big data Data-based prognostic technology can determine the future condition of machines, laying the foundation for intelligent maintenance planning. By Moritz von Plate On the cover: The Kendall Cogeneration Station in Cambridge, Massachusetts, US. Photo credit: Jon Reis Photography
  5. 5. www.cospp.com 3 ISSN 1469–0349 Chairman: Robert F. Biolchini Vice Chairman: Frank T. Lauinger President and Chief Executive Officer: Mark C.Wilmoth Executive Vice President, Corporate Development and Strategy: Jayne A. Gilsinger Senior Vice President, Finance and Chief Financial Officer: Brian Conway Group Publisher: Rich Baker Publisher: Dr. Heather Johnstone Managing Editor: Dr. Jacob Klimstra Associate Editor: Tildy Bayar Contributing Editor: Steve Hodgson Design: Keith Hackett Production Coordinator: Kimberlee Smith Magazine Audience Development Manager Jesse Flyer Sales Managers: Tom Marler Roy Morris Veronica Foster Advertising: Tom Marler on +44 (0)1992 656 608 or tomm@pennwell.com Roy Morris on +44 (0) 1992 656 613 or rmorris@pennwell.com Veronica Foster on +1 918 832 9256 or veronicaf@pennwell.com Editorial/News: e-mail: cospp@pennwell.com Published by PennWell International Ltd, The Water Tower, Gunpowder Mill, Powdermill Lane, Waltham Abbey, Essex EN9 1BN, UK Tel: +44 1992 656 600 Fax: +44 1992 656 700 e-mail: cospp@pennwell.com Web: www.cospp.com © 2015 PennWell International Publications Ltd.All rights reserved. No part of this publication may be reproduced in any form or by any means,whether electronic,mechanical or otherwise including photocopying,recording or any information storage or retrieval system without the prior written consent of the Publishers. While every attempt is made to ensure the accuracy of the information contained in this magazine,neither the Publishers, Editors nor the authors accept any liability for errors or omissions. Opinions expressed in this publication are not necessarily those of the Publishers or Editor. Subscriptions: Qualified professionals may obtain free subscriptions by visiting our website at www.cospp.com and completing an online subscription form.Extra copies of these forms may be obtained from the publisher.The magazine may also be obtained on subscription; the price for one year (six issues) is US$133 in Europe,US$153 elsewhere,including air mail postage.Digital copies are available at US$60.To start a subscription call COSPP at +1 847 763 9540.Cogeneration and On-Site Power Production is published six times a year by Pennwell Corp.,The Water Tower,Gunpowder Mill,Powdermill Lane,Waltham Abbey,Essex EN9 1BN,UK,and distributed in the USA by SPP at 75 Aberdeen Road,Emigsville,PA 17318-0437.Periodicals postage paid at Emigsville,PA. POSTMASTER: send address changes to Cogeneration and On-Site Power Production,c/o P.O.Box 437, Emigsville,PA 17318. Reprints: If you would like to have a recent article reprinted for a conference or for use as marketing tool,please contact Rae Lynn Cooper.Email: raec@pennwell.com. www.cospp.com 22 8 29 Genset maintenance dos and don’ts Because proper maintenance is as critical as the unit itself, we offer top tips for maintaining your standby power installation. By Tyson Robinett 32 Packaging CHP We look at the latest developments in packaged combined heat and power systems to find out why good things come in ever-smaller packages. By Tildy Bayar Opinion 12 A bridge to economic development How fast-track power solutions can provide developing nations with rapid access to reliable generating capacity and a better quality of life. By Laurence Anderson Regulars 4 Editor’s Letter 6 Insight 34 Genset Focus 36 Diary 36 Advertisers’Index
  6. 6. Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com4 Editor’s Letter About being best or super-best W hen three people stand on the podium to receive an Olympic plaque or to be honoured for a World Championship, I often think it is not fair that only one gets gold, and the others silver and bronze. For me, all three are super achievers. The difference between the top athlete and the second- and third-place winners is often miniscule, and generally depends on just a bit of good luck. In many cases there is even evidence that a silver winner is very unhappy, since just a fraction more effort would have yielded the golden plaque. Having been so close to the absolute championship can cause frustration for an extended period of time. A bronze winner, however, is often grateful for having reached the podium, and leaving the bulk of the contestants behind is already felt as a great achievement. Okay, bronze is not gold, but there is still the silver winner in between. Next time when you watch the celebration of a championship, you can verify this story just by looking at the faces of the winners. But apart from the psychology, I like to stress that in sports nowadays, the difference in performance between winners and losers is very small. The ultimately achievable results are asymptotically approaching the theoretical limit. I was thinking about sports championships a few times at POWER-GEN Asia in Bangkok in early September. On the power generation technology track, we had a session on gas turbines and one on reciprocating engines. In each session, four competing original equipment manufacturers highlighted the energy economy of their equipment. These eight presenters showed close to the same fuel efficiency. This means that they all follow the latest technology and apply state-of- the-art developments.Combined cycles based on gas turbines approach the 61% fuel efficiency level, while reciprocating engines appear to reach an amazing 50% efficiency level in simple cycle mode. Listening to almost the same story from each presenter was a little weird. Some speakers had even borrowed pictures from their competitors to show the benefits of their products. In a restaurant, you don’t repeat the order to the waiter if you’d like to have the same menu as your table mate; you just say,“I’ll have the same, please”. In the case of the conference, the second, third and fourth speakers could have said: “We offer you the same fuel efficiency as the first speaker”. Next to that, showing only general performance slides during a presentation can be boring. Such presentations closely approach a sales pitch, which is officially forbidden at conferences. To be a real champion who beats the rest, you also have to show the durability and repeatability of your products. Having a fraction higher or lower efficiency is not so important in practice. Unexpected downtime and repair costs caused by growing pains, inadequate designs or poor spare-part management are the real issues that can be detrimental to a real- life application. That’s why I would like to see many more papers presenting actual operational results. Papers and presentations giving evidence of good performance and proven lifetime profits are much more relevant than just showing a data sheet.A few days ago, I witnessed a presentation where a manufacturer promised to extend the intervals between maintenance actions by a factor of four and a doubling of the life of crucial components. These are the things that potential customers like to hear, preferably with real-life evidence based on user experience. I would like to invite our readers to send us articles on such subjects. They would be very welcome in this magazine. PS: Visit www.cospp.com to see regular news updates, the current issue of the magazine in full, and an archive of articles from previous issues. It’s the same website address to sign-up for our weekly e-newsletter too. Dr Jacob Klimstra Managing Editor
  7. 7. Engine and Marine Systems Power Plants Turbomachinery After Sales Go for Gas For ᣝexibility in an era of renewables As we enter an age of renewables, the V35/44G is a great source of power, and a great source of ᣝexibility. It is the ᣞrst fully electronic four-stroke gas engine from MAN Diesel & Turbo, and combines exceptional efᣞciency, proven reliability and excellent TCO. The V35/44G produces up to 10.6 MW, making it ideal for industrial applications and local electricity generation, including CHP. Discover the power of MAN gas technology: www.mandieselturbo.com For more information, enter 3 at COSPP.hotims.com
  8. 8. Insight 6 Steve Hodgson Contributing Editor H ow extensive is the role played by decentralised energy in power systems across the world? This is not an easy question to answer, partly because there doesn’t appear to be any globally- gathered data, and partly because no two definitions of decentralised energy agree. It is certainly growing, though, as all the major analysts agree. The world’s power systems are therefore in the early stages of a transformation to a ‘cleaner, more local future’, as Michael Liebreich of Bloomberg New Energy Finance described it this summer. Liebriech makes the point that there is more going on than the rise of renewables and decarbonising electricity generation: ‘There is a third level on which the struggle between defenders of clean and fossil energy must be understood, and that is in terms of the social structures in which we want to live.’ Liebreich continues: ‘While fossil-based energy lends itself to scale and centralisation ... clean energy is inherently more local, more distributed, more accountable.’ Though sometimes confused, the two terms – decentralised and renewable – are by no means synonymous. Some renewables technologies just don’t fit the decentralised description at all – I’m thinking of remote, utility- scale (and usually utility-owned) offshore wind farms, and the largest ground-mounted PV arrays. But it’s true that large proportions of the rest are local in nature – feeding their output to the host building or industrial facility, or at least connecting to local, low voltage distribution grids. Anyway, it’s not easy to find reliabledataonjustdecentralised generation, although there have been attempts in the past to quantify the global picture. A decade ago, an article in COSPP magazine by Amory Lovins of the US-based Rocky Mountain Institute (RMI) suggested that decentralised generation – it also used the term micropower – was, even then, bigger than nuclear in both installed capacity and annual output. The RMI included most renewables in its definition of decentralised generation and suggested a global micropower capacity of 400 GW back then, of which around 65% was fossil- fuelled CHP; i.e., around 260 GW. The RMI says that, globally, micropower now accounts for slightly more than 25% of power capacity, up from about 16% in 2004. Whatever the history, the current direction of travel is clear and power systems are having to change. One organisation that has to fully understand how systems should evolve to accommodate decentralised generation is the transmission and distribution system operator. Homing in on just one country, Britain’s National Grid predicts that small-scale distributed generators will represent a third of total UK generating capacity by 2020, adding that the concept of baseload supply will be turned on its head, so that distributed generators will supply baseload power, and large-scale centralised plants will be used to meet peak demands and fixed loads from businesses. Demand- side response and management will enable the market to balance supply and demand. This would be quite a different system to that of a few years ago, in which large and remote coal, gas and nuclear-fuelled power stations were dispatched centrally, with smaller oil-fired stations and pumped storage plants used to balance the system. Energy flowed in just one direction – from generator to user. Now, thousands of (much smaller) power stations switch themselves on as the sun rises, the wind blows or the plant operator sees fit according to local loads, and power flows in both directions. Renewable or not, decentralised energy is changing electricity. A more local energy future Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com
  9. 9. ᣝ Customer: Business district energy system. ᣝ Challenge: Increase efficiency and reduce energy costs. ᣝ Result: Elliott steam turbine generators replaced PRVs to produce valuable on-site electricity. They turned to Elliott to light up their bottom line. The customer turned to Elliott Group to boost energy efficiency with steam turbine generators in place of pressure reducing valves. Their “purchased energy” costs paled, and the bottom line got brighter. Who will you turn to? C O M P R E S S O R S ᣝ T U R B I N E S ᣝ G L O B A L S E R V I C E www.elliott-turbo.com The world turns to Elliott. For more information, enter 4 at COSPP.hotims.com
  10. 10. Policy & markets: USA Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com8 Forthcoming US federal regulations on emissions reduction are generally positive for distributed energy but have created uncertainty within the industry, finds Craig Howie T he US Environmental Protection Agency (EPA) released the final version of its heavily anticipated Clean Power Plan (CPP) in early August, after several revisions and some 4.3 million comments submitted within the public consultation period on the 1560 pages of regulations which have lasted since the EPA first announced its plans for new limits in September 2013. The agency’s goal is to reduce carbon emissions by 32% below 2005 levels by 2030, and to provide America’s first national standard to limit pollution from power plants. US states are expected to show compliance with the recommendations by 2022, on a gradual ‘glide path’ of emissions reductions to 2030. The plan is being authorised under existing primary legislation – the Clean Air Act – so it does not have to be presented to Congress for approval. The Obama administration expects that implementing these emissions limits will cost $8.4 billion annually by 2030. After the plan is entered into the Federal Record, which could happen as COSPP goes to press,it will be subject within 60 days to an expected legal challenge from 15 states which are largely invested in the coal industry, and which do not necessarily have significant distributed energy schemes planned or in place. Many in the industry have compared the regulations to the 2010 effort to create New US policy A boon for distributed energy? Absorption chiller at St Peter’s University in New Jersey Credit: ENER-G Rudox
  11. 11. Policy & markets: USA www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 9 a national cap-and-trade scheme for carbon emissions – a plan that failed to pass the US Senate. At the CPP’s release, President Barack Obama said: ‘There is such a thing as being too late when it comes to climate change.’ Distributed energy is expected by many to benefit from the new rules, as decentralised, small-scale power production that can be aggregated to meet regular demand, often linking with main grids, is a good fit. Of course, it helps that it can take the form of renewables such as solar and wind power, or harness biogas or biomass and geothermal power, and often incorporate combined heat and power (CHP). Rob Thornton, president and CEO of the International District Energy Association (IDEA), which has been working with the EPA for 15 years and has contributed to the language and provisions in the CPP’s current and revised forms, said the plan is‘a structured federal guidance to the states to make the electric generating industry more efficient’. The emissions regulations are ‘generally favourable’ for the distributed energy sector, he suggested, but added that the ‘devil is in the details,’ acknowledging the states’ legal challenges. ‘We see it as being operable in certain states; other states remain to be determined.’ States are expected to present their own plans to achieve emissions reductions in line with the federal regulations, and can comply by employing one of two mechanisms.They can operate on a rate-based system, where they are allowed a certain level of emissions per MWh per unit; or on a mass-based quota that sets an allowance for aggregate total emissions. The rules will affect states in different ways depending on which system they choose. ‘I think CPP is a reasonable compliance measure that can help those states at least move the needle on reducing emissions,’Thornton said. Moving the needle To illustrate how distributed energy can be utilised to reduce emissions, Thornton points to Kendall Cogeneration Station in Cambridge, Massachusetts, a 256 MW gas-fired plant which, under prior ownership, was a market- based electricity generator. Now under new ownership, the station recovers heat that was being rejected into the Charles River, dramatically improving the heat rate of the plant, reducing thermal pollution and supplying more heat to the district network, where it is displacing unregulated boilers. Thornton said some environmental groups have expressed disappointment that the plan does not lay out an energy vision that is 100% based on renewables such as wind and solar power, but, to Thornton,‘incremental change is better than none’. He notes that ‘CPP gives us a vehicle from which to explain and demonstrate the advantages of distributed energy, particularly at scale.’ The state of Massachusetts is a leading proponent of distributed power alongside California, New Jersey and Maryland. And state-based emissions initiatives have given it a head start in complying with the federal emissions legislation, notes Moe Barry, a spokesman for Energy Choice, a Somerville, Massachusetts- based provider of power generation and CHP units The InteliSysNT and InteliGenNT ranges are high quality, reliable generating-set controllers with ideal features for CHP. ᣞ ᣞᣟᣠᣡᣞᣢᣣᣡᣤᣡᣥᣞᣦᣡᣤᣞᣧᣨᣩᣞᣪᣣᣞᣫᣪᣦᣥᣞᣬᣭᣣᣡᣞᣮᣪᣭᣣᣞᣪᣯᣦᣞᣰᣪᣣᣞ ᣱᣞᣲᣞᣡᣳᣴᣵ᣶ᣡᣞᣠᣮᣠ᣷ᣡ᣸ᣞ᣷᣹ᣱ᣷᣺ᣠᣞ᣷ᣱᣴ᣶ᣪᣣᣡᣤᣞ᣷ᣪᣞᣮᣪᣭᣣᣞᣦᣡᣡᣤᣠ ᣞ ᣞ᣻ᣪᣢ᣹ᣴᣠ᣷ᣴᣫᣱ᣷ᣡᣤᣞᣱᣦᣤᣞᣴᣦ᣷ᣭᣴ᣷ᣴ᣼ᣡᣞ᣻ᣩ᣽᣾᣽ᣞᣠᣮᣠ᣷ᣡ᣸ᣞ ᣞ ᣞ᣾ᣡ᣷ᣱᣴ᣶ᣡᣤᣞ᣹ᣴᣠ᣷ᣪᣣᣮᣞ᣶ᣪᣬᣞᣡᣦᣠᣭᣣᣡᣠᣞᣱᣫ᣷ᣴ᣼ᣴ᣷ᣮᣞ ᣸ᣪᣦᣴ᣷ᣪᣣᣴᣦᣬᣞᣰᣪᣣᣞᣪᣢ᣷ᣴ᣸ᣱ᣶ᣞᣪᣢᣡᣣᣱ᣷ᣴᣪᣦᣞᣱᣦᣤᣞᣫᣪ᣸ᣢ᣶ᣡ᣷ᣡᣞ ᣤᣴᣱᣬᣦᣪᣠ᣷ᣴᣫᣠ ᣞ ᣞ᣿ᣴᣬ᣹ᤀᣣᣡᣠᣪ᣶ᣭ᣷ᣴᣪᣦᣞᣫᣪ᣶ᣪᣭᣣᣞᤁᣦ᣷ᣡ᣶ᣴᤂᣴᣠᣴᣪᣦᣞᤃᤄᤅᣪᣭᣫ᣹ᣞ ᣤᣴᣠᣢ᣶ᣱᣮᣞ᣸ᣱᤆᣡᣠᣞᣴ᣷ᣞᣠᣴ᣸ᣢ᣶ᣡᣞ᣷ᣪᣞ᣸ᣪᣦᣴ᣷ᣪᣣᣞᣱᣦᣤᣞᣫᣪᣦ᣷ᣣᣪ᣶ᣞ ᣶ᣱᣣᣬᣡᣞᣱ᣸ᣪᣭᣦ᣷ᣠᣞᣪᣰᣞᣤᣱ᣷ᣱ ᣞ ᣞ᣻ᣡᣫᣭᣣᣡᤇᣞᣡᣱᣠᣮᣞ᣷ᣪᣞᣭᣠᣡᣞᣣᣡ᣸ᣪ᣷ᣡᣞ᣸ᣪᣦᣴ᣷ᣪᣣᣴᣦᣬᣞ ᣱᣦᣤᣞᣫᣪᣦ᣷ᣣᣪ᣶ᣞᣯᣴ᣷᣹ᣞ᣸ᣱᣣᤆᣡ᣷ᤀ᣶ᣡᣱᣤᣴᣦᣬᣞᣩᣪ᣸᣽ᣢᣞ ᤈᣡᣵ᣻ᣭᣢᣡᣣ᣼ᣴᣠᣪᣣᣞᣱᣦᣤᣞ᣽ᣴᣣᤉᣱ᣷ᣡᣞ᣷ᣡᣫ᣹ᣦᣪ᣶ᣪᣬᣮᣞ᣼ᣴᣱᣞ ᣧᣩᤇᣞ᣷ᣱᣵ᣶ᣡ᣷ᣞᣱᣦᣤᣞᣠ᣸ᣱᣣ᣷ᣢ᣹ᣪᣦᣡᣞ ᣞ ᣞ᣽ᣤ᣼ᣱᣦᣫᣡᣤᣞᣢᣣᣪ᣷ᣡᣫ᣷ᣴᣪᣦᣠᣞ᣷᣹ᣱ᣷ᣞᣡᣳᣫᣡᣡᣤᣞᣭ᣷ᣴ᣶ᣴ᣷ᣴᣡᣠ᣺ᣞ ᣣᣡᤊᣭᣴᣣᣡ᣸ᣡᣦ᣷ᣠᣞᣯᣴ᣷᣹ᣞ᣷᣹ᣡᣞᤁᣦ᣷ᣡ᣶ᣴᣧᣣᣪᣞᣢᣣᣪ᣷ᣡᣫ᣷ᣴᣪᣦᣞ ᣣᣡ᣶ᣱᣮᣞ ᣞ ᣧᣣᣪ᣼ᣡᣦᣞᣠᣪ᣶ᣭ᣷ᣴᣪᣦᣠᣞ᣷ᣣᣭᣠ᣷ᣡᣤᣞᣵᣮᣞᣩ᣿ᣧᣞᣡᣳᣢᣡᣣ᣷ᣠ Perfect solutions for CHP www.comap.czᤅ᣿ᤋᤌᤋ᣺᣻ᣞ᣽ᣞᣩᤍᤎ᣽ᣧᣞ᣻ᤍᣨᣟᤅᤁᤍᤏᣞᤐᤍᤌᣞᤋᤂᤋᤌᤑᣞ᣽ᣧᣧᣨᤁᣩ᣽ᤅᤁᤍᤏ For more information, enter 5 at COSPP.hotims.com
  12. 12. Policy & markets: USA Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com10 rated from 100 kW to 7.5 MW. The CPP rules were not a surprise within the industry, Barry says. ‘More stringent emissions regulations have been consistently happening, it’s something we anticipated happening.’ Energy Choice’s main focus is utilising natural gas to collect biogas emissions through reciprocating engines. Barry suggests that the key impact of the federal rules will add some cost to smaller projects through the addition of emissions- reducing technology such as selective catalytic reduction (SCR), which may deter some buyers seeking units from 500 kW to 7.5 MW. ‘Emissions catalysts can make a project less feasible. You can still do it and you can hit the emissions regulations, it’s just [that] costs for some of these beneficial CHP technologies are a little more difficult and harder to finalise,’ says Barry. But he says the CPP ‘really makes us confident we can go to any part of the country, where traditional forms of power generation aren’t feasible anymore. In the northeast, we’re able to soften the fear of what’s permissible today and may be permissible tomorrow.’ The CPP could also affect one of America’s main users of distributed energy: university campuses. Princeton University in New Jersey has also benefited from the state’s long- standing initiatives to promote microgrids that provide more reliability and resilience of supply, of particular importance when the state dealt with Hurricane Sandy and its aftermath in 2012.When the hurricane hit, the university’s 15 MW of power provided by a GE LM1600 gas turbine serving 180 buildings and 12,000 people helped keep the research facilities running. Vital projects in the university’s data centre could have been lost without a separate 1.9 MW gas-fired reciprocating engine that provides cooling power from waste energy. The university has also installed 16,528 solar panels. With a setup like this already in place, Ted Borer, Princeton’s energy plant manager, says that the ‘shock to the system’ of any new federal regulations ‘wouldn’t be nearly as strong. We’re burning natural gas as our primary fuel.Diesel is only a backup, so there is low or zero impact at our scale’ from the CPP, Borer explained. Alongside facilitating the use of distributed power by way of renewables including solar and wind, some CHP companies invested in natural gas see increasing benefits from the CPP regulations. Tim Hade, a spokesman for New York-based ENER-G Rudox, which has supplied some 4000 backup power generators utilising cogeneration, says: ‘We’re very interested in the outcome of CPP and, in particular, how it’s going to be implemented.Right now there’s a lot of uncertainty,but CPP is a step in the right direction. ‘What will come out on the other side,’ he says, ‘is policy that integrates greater use of natural gas.’ ‘Ultimately we’re looking at what states are doing in order to comply, forward-thinking the process that they come up with to meet targets. That’s a state we’re very interested in focusing on. Conversely, if a public utility is fighting the rule, then we’re probably going to stay away from those states.’ However, some distributed power providers see benefits in seeking business in coal-reliant states, seeing greater potential than in states that already have many such systems in place. Some 15 states have joined a potential lawsuit to challenge the CPP. While the challenge is being led by West Virginia, which is synonymous with America’s coal industry, states involved in the lawsuit from the Midwest including Indiana, Michigan and Ohio also present significant opportunities for CHP providers, said Patricia Sharkey, policy director for the Midwest Cogeneration Association (MCA), which has been working to educate its member organisations throughout coal- reliant states. The MCA is working to pull together a distributed energy template in partnership with the Great Plains Institute, while working on a potential eight-state compact to become ‘trading ready’ or by way of a mass-based emissions plan. Some states will be dragged into the CPP ‘kicking and screaming’, Sharkey said, as it is a better alternative than refusing to follow the regulations, which then would involve greater federal oversight and allocation of state energy resources. ‘Some utilities are very friendly to the notion that we’re moving into new era of distributed generation as part of the overall energy mix. Others are fighting it tooth and nail. Indiana [has] a lot of resistance; [there is] a big battle in Michigan. Ohio [is] split also. That tells you that some of the industry groups really understand that energy efficiency can lower the energy costs,’ Sharkey noted. ‘They have the potential to be doing the kind of projects in our coal states, have the potential to offset coal emissions and keep those plants going because they’re able to buy allowances from the industrial CHP generators.’ Such additional funds could be valuable given that distributed energy and CHP projects in the Midwest can also be hindered by smaller- margin spark spreads, lack of money for regional greenhouse gas initiatives,and reductions in The Kendall Cogeneration Station in Cambridge, Massachusetts Credit: Jon Reis Photography
  13. 13. Policy & markets: USA www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 11 federal aid for natural disaster planning and response, which can feed into distributed energy.Even then,Sharkey says, legislators in coal-reliant states are keeping an eye on how other states are responding to the CPP legislation, as a means of developing a ‘Plan B’ response to avoiding the federal oversight and allocation plan:‘There’s a lot of push and pull, but the CHP component is getting a lot of attention. CPP is one more thumb on the scale for CHP.’ One state without such residual opposition is California, which has learned its lessons from its energy crisis of 2000–2001 when capacity shortages led to blackouts. It has, as a result, pursued distributed energy as a matter of political necessity. The state’s use of coal in electricity generation is practically negligible, and it operates an energy cap-and- trade system under the nation’s most stringent greenhouse gas emissions regulations. Some 19% of its electricity comes from renewable sources, according to the California Energy Commission. Beth Vaughan, executive director of the California Cogeneration Council, said that her group has fielded multiple calls from businesses headquartered outside the state with one question: How will this affect us? But Vaughan, who has also held positions in the Canadian and New Zealand governments advising on climate change issues, cited a lack of widespread distribution of information at the federal level as contributing to an air of uncertainty about the new regulations within the distributed power industry. ‘Dissemination of information is not consistently done at a national level; you need to get the communication in the background,’ she says. Despite this, the message to companies already operating within California’s heavily regulated economy is: ‘Don’t worry, you’re already covered’, Vaughan says. However, she notes that also high on the priorities list should be:‘How do we go the extra mile?’ This is a message that the AmericanCouncilforanEnergy Efficient Economy, a non-profit research organisation based in Washington DC, may have taken to heart. In the wake of the CPP’s release, the group has worked to convene energy producers, distributers and users in working groups to discuss the way CHP is treated under the new EPA rules. Meegan Kelly, a senior research analyst with the group, thinks that such outreach will help the EPA reach its goal of significant emissions reduction across America. ‘We think that the CPP could represent a big opportunity for the distributed energy sector and CPP can help states achieve significantly lower emissions, increase competitiveness and energy reliability and resiliency,’ Kelly says.‘Business owners are likely to benefit from the cap-and- trade aspect, lower operating costs and by investing in efficiency.’ Craig Howie is a journalist based in Washington, DC This article is available on-line. Please visit www.cospp.com For more information, enter 6 at COSPP.hotims.com SOHRE TURBOMACHINERY® SHAFT GROUNDING BRUSHES SELF CLEANING OPERATE DRY OR IN OIL GOLD/SILVER BRISTLES LITTLE OR NO MAINTENANCE CAN BE SERVICED DURING OPERATION TRANSMIT INSTRUMENT SIGNALS FROM ROTOR WITHOUT SPECIAL SLIPRINGS Are stray electrical currents destroying your bearings and seals? WWW.SOHRETURBO.COM ï INFO@SOHRETURBO.COM ï PH: +1.413.267.0590 ï MONSON, MASSACHUSETTS, USA
  14. 14. Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com12 Opinion A bridge to economic development Fast-track, turnkey power can provide developing nations with rapid access to reliable generating capacity and a better quality of life, argues Laurence Anderson Fast-track power: A ccording to the I n t e r n a t i o n a l Energy Agency, 1.3 billion people – 18% of the world’s population – are currently without access to electricity, and that number is expected to grow by 2.1% per year through 2040. Approximately 80% of that growth is forecast to occur in non-OECD countries throughout Africa, Latin America and Asia, largely due to rapid global population growth that is spurring industrialisation, demand for a better quality of life and a significant rise in the use of electronic devices and power- intensive appliances such as refrigerators. The need for additional generating capacity has only grown more crucial, and a number of countries and governments have voiced commitments to bridging the growing gap between supply and demand. In Southeast Asia, for instance, Indonesia’s government has pledged that the nation would be 99% electrified by 2020 – no small order considering that the current electrification rate is approximately 74% and some 60 million people lack power. In the Philippines, the challenge to meet that country’s pledge to attain 99% electrification by 2017 seems even more daunting, with approximately 29 million people – roughly 30% of its population – currently without access. Similarly, in the US, the Obama administration issued a much-publicised pledge last year to bring 30,000 MW of new generating capacity to Africa.To date, according to a recent administration estimate, the Power Africa initiative has resulted in approximately 2500 MW of new capacity. That’s enough to power about 3.5 million homes on a continent where the Africa Progress Panel estimates 621 million lack electricity and the population is forecast to double by 2040. While the panel suggests that solar power is the key to Africa’s future, the fact remains that a diverse portfolio of generating technology is needed to offset and compensate for the disadvantages inherent in any power technology. In the case of solar, beyond the limitation of intermittent sunshine, there’s also the issue of high initial cost. Therefore, with or without the financial assistance and incentives that would be needed for a massive solar build-out in Africa and other developing regions, conventional fossil- powered generation is likely to remain part of the mix for the foreseeable future. The same need for diverse sources of power generation can be found in those parts of the world that are heavily reliant on other renewables, such as hydropower. Whether it is due to the annual dry season or unexpected droughts, a number of developing nations in Africa, Asia and South America would benefit from the availability of supplemental or backup generation. Perhaps the greatest challenge to closing the power gap facing developing nations is that bringing permanent electric generation online – from planning and financing to construction and eventual commissioning – can take years.Throw in the lack of available financing, political instability, permitting hurdles and socio-political events, and the timeline can become insurmountable for many developing nations. But that doesn’t mean that the 1.3 billion people lacking electricity should have to go years – even decades – waiting for this essential ingredient for economic development and a better quality of life. Reliable power generation – fast Fast-track, turnkey power, available using state-of-the- art gas turbine technology and diesel- and gas-powered reciprocating generators, offers myriad benefits as a bridge to a better quality of life and economic growth while permanent power stations are progressing along the long path to reality. Among the benefits of interim fast-track power are: • Mobile power modules and gas turbines are easily transportable by land, sea and air; • Power modules and gas turbines can be bundled, providing scalable generating capacity from approximately 10 MW to 500 MW or more; Laurence Anderson
  15. 15. www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 13 Opinion • Installation and commissioning are rapid due to minimal construction and setup required for this modular solution; • Rapid installation means reliable power in weeks not years – for as long as the need exists; • Distributed power means the capacity can be located near demand, reducing the need for transmission and distribution infrastructure, while also cutting the power loss that occurs as electricity travels long distances across the grid; • Up-front customer investment is minimal, avoiding long-term financing and credit issues; • Mobile, modular design allows the plants to be rapidly demobilised and removed from the site when a permanent solution becomes available. A promising future Beyond the pent-up demand for power and the long timeline to bring permanent generation online, I am seeing three other factors that should drive increased adoption of interim fast-track power. The first is that on-site power solutions can be tailored to the unique requirements of each country and customer. Developing nations increasingly need a range of technologies and types of fuels and voltages, as well as scalability in project size and duration. In addition, services that encompass engineering and design, project planning, installation, construction, commissioning, operation and maintenance,balance of plant and decommissioning are especially attractive in remote areas of the developing world looking to industrialise and grow their local economies. Case in point is our recent project in Myanmar,where 70% of the population lives in rural locations and approximately three quarters of the people are without electricity. In 2014, APR Energy signed the first agreement between a US- based power generation company and the government of Myanmar since the lifting of sanctions by Western nations. Within 90 days, the company had installed and commissioned 82 MW of gas- fired power and later added another 20 MW of capacity. While this fast-track solution provides the power equivalent needed to electrify six million homes in central Myanmar, this generation predominantly is being used to grow the country’s manufacturing base south of Mandalay. As Myanmar manufacturing expands, jobs are created, household income and purchasing power rises, and the production of revenue- generating export products grows. The suitability of mobile, modular generating equipment also makes this an ideal solution for energy- intensive industries such as mining, where operations typically are in remote locations, far removed from the power grid. Remote mining projects in places like Botswana and Mozambique required round-the-clock power and the ability to meet variable load requirements until the power was no longer needed. The second factor that I see driving growth for interim, fast- track power is an increased demand for mobile gas turbines, which offer a higher power density, resulting in a reduced footprint, and lower emissions and quieter operation than reciprocating generators. They also provide significantly greater grid stability, as well as ancillary services such as spinning reserves, positive frequency control and power system stabilisation. The growing interest in gas turbines brings me to the third factor I see driving growth in interim fast-track power: the shale gas explosion and a shift to abundant, low-cost natural gas as a fuel of choice for electric generation. In developing nations rich in these natural resources, declining worldwide hydrocarbon pricing and reduced export revenues have become a disincentive for exploration-and-production companies to tap into vast reserves off the coast of West Africa, parts of Southeast Asia and elsewhere. Mobile gas turbines are an ideal way for these nations to monetise the economic value of their idle gas resources, and to transform this energy into electric power that will support industrialisation and manufacturing of products that might generate higher export revenues. Then, as the economic wealth of these developing countries grows – thanks to this gas turbine-powered bridge – they will begin to amass the financial resources to invest in permanent generation. A meeting at the Center for Strategic and International Studies, held this past May, provided an early glimpse into what future demand might look like for LNG. An executive from the Panama Canal Authority explained that when the expansion of the locks was being designed, LNG shipments were not a consideration. When the expansion is completed in the next year, two LNG shipments per week from the US are expected to pass through the canal,en route to Asia – quickly ramping up to three shipments per day. The executive noted that, one day, some of the LNG passing through the canal could be off-loaded in Panama – opening the door to the possible creation of a regional electricity hub, fueling 300 MW–400 MW of combined- cycle generation to serve Panama and its Colombian neighbors to the south, and Costa Rica and Nicaragua to the north. The interim power industry is ideally positioned to provide a bridging solution that utilises mobile gas turbines while permanent LNG-powered generating capacity is developed – in Central America and across the globe. Bridge to a better life While the challenge of providing reliable electric power to the billions of people living in developing and remote parts of the world is massive and growing, it is one that can – and will – be overcome. My optimism is fueled by a simple truth: the benefits of providing this essential ingredient far outweigh the cost of these commitments. That said, permanent power generation – much like Rome – can’t be built in a day. Fortunately, with interim fast-track power, we have a readily available bridge that can facilitate near-term industrial growth and help developing nations and billions of people around the world to attain the improved quality of life they desire. Laurence Anderson is CEO of APR Energy www.aprenegy.com This article is available on-line. Please visit www.cospp.com
  16. 16. Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com14 The modern-day microgrid Microgrids: more than remote power Microgrids offer an economical way to ensure continuity of power supply and protection against grid faults and emergency situations,write Celine Mahieux and Alexandre Oudalov . R ecentyearshaveseen a significant growth in interest in microgrids as a way of providing access to electricity in off-grid locations like remote villages, mines and islands. Now, microgrids are increasingly being deployed as a way to improve local power resilience, reduce reliance on fossil fuels and defer large- scale grid investments in areas that have a connection to the main electricity grid. This ‘grid-connected’ version of microgrids is growing in popularity as a way to meet rising power demands, take advantage of the falling cost of renewable sources, and improve supply resilience and autonomy (especially for critical applications). They provide an economical way of ensuring continuity of supply and protection against grid faults and emergency situations. While many microgrids still rely on diesel generators as their energy source, the falling costs of wind and solar power, the availability of efficient energy storage technologies and the availability of affordable wide-area communication infrastructure are making microgrids based on multiple generation sources a highly attractive proposition. Modern microgrids combine distributed energy resources and loads in a controlled, co-ordinated way. Grid- connected microgrids can also deliver additional value by supporting the grid restoration process after a major failure (black-start capability) and bolstering the grid during periods of heavy demand. At the same time, energy suppliers and industrial and commercial users are increasingly interested in moving away from reliance on fossil fuels and drawing from more sustainable and eco-friendly sources such as solar and wind. In areas where the grid is weak, microgrids can provide a reliable electricity supply while dramatically reducing fuel consumption and carbon footprint.They offer the flexibility and scalability to grow in line with demand, and can be deployed in significantly less time than that needed to complete a grid expansion project. The ability to isolate such microgrids from the main grid seamlessly when needed is an important feature. Fast- reacting energy sources play a vital role in providing the resilience to ensure continuity of supply for critical loads. The modern microgrid In many ways, microgrids are scaled-down versions of traditional power grids. A key distinguishing feature is their Microgrids are increasingly being deployed in grid-connected areas Credit: ABB
  17. 17. The modern-day microgrid www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 15 Engenharia e Equipamentos TÈrmicos, S.A. 3060-197 Cantanhede - Portugal Tel: +351 231 410 210 - Fax: +351 231 410 211 E-mail: ambitermo@ambitermo.com - www.ambitermo.com Standard Industrial Boiler Energy RecoveryEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEnnnnnnnnnnnnnnnneeeeeeeeeeeeeeeeeeeeerrrrrrrrrrrrrrrgggggggggggggggggyyyyyyyyyyy RRRRRRRRRRRRRRRRRRRRRRRRRRRRRReeeeeeeeeeeeeeeeeeeeeeeeeeccccccccccccccccccccccccccccoooooooooooooooooooooooovvvvvvvvvvvvvvvvvveeeeeeeeeeeeeeeeeeerrrrrrrrrrrrrrrryyyyyyyyyyyyyyyyEEEEEEEEnneeeeerrrrgggggggggyyyyyyyy RRReeeeeeccccccccooooovveeeerryyyyyyy SSSSSSSSSSSSSSSSSSSSSSSStttttttttttttttttttaaaaaaaaaannnnnnnnnnnnnnnnnnnddddddddddddddddddddddddaaaaaaaaaarrrrrrrrrrrrrddddddddddddd IIIIIIIIIIIIIIIIInnnnnnnnnnnddddddddddddddddddddddddddddddddduuuuuuuuuuuuuuuuuuuusssssssssssssssssssssssssssssssstttttttttttttttttttttttttttttttttttttttrrrrrrrrrrrrrrriiiiiiiiiiiiiiiiiiiaaaaaaaaaaaaaalllllllllllllllllllllllllllll BBBBBBBBBBBBBBBBBBBBBBBBBBBBBooooooooooooooooooooooiiiiiiiiiiiiiiiiiiiiiiiiiilllllllllllllllllllleeeeeeeeeeeeeeeeeerrrrrrrrrrrrrrrrr EnEEnEngEnEngEngEngEnEngggggEngEngEngEnggggggggg hhhenhenenenhenhenhhenhenhenenhhenhenhenhenhen iiiariariararariariararararararararirara a ea ea eea ea ea eaa EEqEqEqEqEqEqEqEquipuipuipuipuipuipuipuipuipameamementotonton s Ts Ts TÈrÈrmÈrmÈrmÈrmicicoicoicoss, S.A.AAS.A. 30630630630630630630630630630630630663063060306630630630630630666630630630630630630630630630600 000000000000000000000000000--------1971971971971971971971971971971979197197197197197719719779191971971971979 CaCaCaCaCaCCaCaCaCaCaCaCaCaCaCaCaCaCaCaCantantantantantantantannntannnntann hehehenhenhenhenhehehehehenhehenhenhenhehehedddededededededededeeeddedede ------ PorPorPorPorPorPPorPorPPorPorPorPorPorPorrPorPorttugtugtugtugugugugugugugugugggalalaala TTTTelTelTelTelTTelT lel: +: ++++: +:: 35133351351351113513515151351351 232323232323232231 41 41 41 4441 410101010110101010101010010 2102102102102102102102210210210210210 -- FFaxFaxFaxaxaxFaxaxaxFF +++++: +: +++::: ++: +: 3515151513513513351151351513513513513511 2323232323232323232323232232322 1 41 41 41 41 41 41 41 41 41 41 441 44441010101010101010101010101010100101010 21121121121121121121121121112112211222112 EEEEEEE--mamaimaimaimamaimamaimaimammmaima l:l:l:l:ll:l:l:l:ll:l::l:l: aambaambmbmbmbmbmbmbambm iteteiteiteteitetteteetetetetermormo@a@am@am@am@am@amm@am@am@ambitbibitbbitermrmermermermermermermo.co.cco.co.co.co.co.comomomomomomomomom - wwwwwwwwwwwwwwwwww amam.amammam.amamam.amammamam..amambibitbitbitttbitbitbitbitbibbbitbitbitbitbi ermermermmermmermermmmermmermmermmmermo.co.co.co.co.co.comomomomom Combined cycle closer proximity between generation sources and user loads. The system can be designed and controlled to increase power supply reliability. Microgrids typically integrate renewable energy sources such as solar, wind power,small hydro,geothermal, waste-to-energy and combined heat and power (CHP) systems. Microgrids are increasingly being equipped with energy storage systems, as batteries become more cost-competitive. The system is controlled through a microgrid control system that can incorporate demand–response so that demand can be matched to available supply in the safest and most optimised way. A flywheel- or battery-based grid stabilising system may be included to offer real and reactive power support. The microgrid control system performs dynamic control over energy sources, enabling autonomous and automatic self-healing operation. During normal usage the grid-connected microgrid will remain physically connected to the main grid. Microgrids interoperate with existing power systems and information systems and have the ability to feed power back to the grid to support its stable operation. At periods of peak load a microgrid may limit the power it takes from the grid, or even reduce it to zero. Only in the case of main grid failure or planned maintenance will it implement a physical isolation of its local generation and loads without affecting the utility grid’s integrity. Resilience and independence Even in developed markets with established grids, there are rising concerns over the resilience and quality of the power supply among certain end-users. In critical applications, grid- connected microgrids are able to disconnect seamlessly (becoming ‘islanded’) and continue to generate power reliably in the event of a fault, natural disaster or even outside attack. In areas where the grid is weak, such grid-connected microgrids satisfy the need to ensure continuity of supply. In recent years microgrids have been suggested as a potential solution after natural disasters in the US highlighted the vulnerability of distribution power grids based on overhead power lines. While absolute power reliability is important in some sectors, many industries are also looking to reduce energy costs and reliance on fossil fuels for peak shaving or backup power, whatever the condition or availability of the main grid. Here, multi- generation microgrids provide the flexibility to take advantage of a number of options for self-consumption. Utilitiescanchoosetodeploy grid-connected microgrids as a way of deferring investment in expansion or upgrading of the main grid. Such deferrals can produce financial value to utilities by reducing capital expenditure in the short to medium term. Smart control of the microgrid’s distributed energy resources and integration into markets enables the provision of ancillary services for the grid operator and creates new value propositions. In grid-connected microgrids, the connection is made through a Point of Connection (POC) or Point of Common Coupling (PCC), which enables it to import or export electricity as commercial or technical conditions dictate. For more information, enter 7 at COSPP.hotims.com
  18. 18. The modern-day microgrid Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com16 Microgrid components Modern microgrid solutions incorporate a number of key components. Control system The first is the microgrid control system, which uses distributed agents to control individual loads, network switches,generators or storage devices to provide intelligent power management and efficient microgrid operation. The system calculates the most economical power configuration, ensuring a proper balance of supply and demand to maximise renewable energy integration. It also optimises the network’s generator operations so the entire system performs at peak potential, and ensures a compliant grid-connected microgrid solution. Power stabilisation and energy storage system Second is energy storage that plays an important role both in microgrid stabilisation and in renewable energy time-shifts to bridge peaks and troughs in power generation and consumption.However,the two functions require very different technologies for energy storage. Flywheel grid stabilisation technology enables a high instantaneous penetration of renewable generation sources by providing synthetic inertia and grid-forming capabilities. This stabilises power systems against fluctuations in frequency and voltage caused by variable renewable sources or microgrid loads. It stabilises the electricity network and reduces downtime by rapidly absorbing power surges or by injecting power to make up for short-term troughs, in order to maintain high-quality voltage and frequency. For microgrid stabilisation the energy storage system must provide a very fast response while possibly being called several times per minute. This demands high power output but small stored energy. For renewable energy time- shifts, battery-based energy storage systems should be capable of storing energy for a few hours to bridge the peaks of energy production and consumption. Meeting both requirements typically requires a hybrid system with a combination of underlying storage technologies, each with different performance characteristics (cycle life and response time). A hybrid energy storage system will combine the benefits of each storage medium and offer lower total cost compared with individual units. Protection system A protection system is needed to respond to utility-grid and microgrid faults. With a utility- grid fault, protection should immediately isolate the microgrid in order to protect the microgrid loads. For faults inside the microgrid,protection should isolate the smallest possible section of the feeder. Optimal energy management system Thermal loads usually represent a considerable part of total energy used by end consumers. There is significant potential for cost savings, particularly through the use of CHP systems, which allow consumers to realise greater efficiencies by capturing waste heat from power generators. Therefore, cost-effective microgrid energy management requires good co-ordination between thermal energy storage and other thermal sources, and between thermal and electrical systems. System planning and design tools System modeling is important during all phases of microgrid development – from the conceptual design and feasibility study, through construction, to final acceptance testing. For example, when an existing diesel-based backup power supply is extended with a large amount of fluctuating renewable energy resources, stable operation of the microgrid cannot be guaranteed. In order to optimally dimension a grid- stabilising device and to tune its control parameters, the dynamic behaviour of legacy diesel gensets has to be known. Grid storage in Australia Australian operator SP AusNet has deployed a containerised microgrid solution encompassing battery, transformer and diesel generator for a Grid Energy Storage System (GESS) in Melbourne, Victoria, Australia. This provides active and reactive power support during periods of high demand, and enables smooth transition into islanded/off-grid operation on command or in emergencies.It has also enabled investments in expanded power line capacity to be deferred. AusNet Services, Victoria’s largest energy delivery service company, began investigating GESS in 2013. It chose to trial the technology to explore its ability to manage peak demand, with the potential to defer investment in network upgrades. The GESS consists of a 1 MWh 1C lithium battery system operating in combination with a diesel generator, transformer and an SF6 gas circuit breaker-based ring main unit with associated power protection systems. Located at an end-of-line distribution feeder in the northernsuburbsofMelbourne, the system was commissioned in December 2014, and is currently undergoing a two-year trial. The GESS is the first system of this type and size in Australia, and the trial aims to explore the benefits to peak demand management, power system quality and network investment deferral. AusNet Services is investigating the capabilities of grid-connected microgrids to provide peak demand support. With a generation source embedded close to the load,the utility aims to study the effect on postponing network investment in feeder line upgrades to support increased loads. The belief is that such an embedded generation source can also be used to provide peak load support by reducing the upstream feeder requirements during peak consumption periods by supplying the loads locally. AusNet is also investigating the effect on local system quality and stability that the GESS will provide, including power ABB’s South African factory is to host a solar-diesel microgrid Credit: ABB
  19. 19. The modern-day microgrid www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 17 factor correction, voltage support, harmonics, flicker and negative sequence voltage suppression. In addition, AusNet is investigating the capabilities of the GESS to operate as an islanded system, and how these improve the reliability of supply and system stability in the case of larger network faults.In the event of a fault,the GESS islands the downstream feeder, creating an islanded microgrid which the GESS supplies until its energy reserves are depleted or the fault is cleared. When the fault is cleared,the GESS reconnects to the grid and transfers the supply back to network and begins recharging the batteries on a scheduled, preset programmed time of day. Heritage building goes carbon-neutral A microgrid solution helped Legion House, an office building in Sydney’s central business district, become Australia’s first carbon-neutral and autonomous heritage- listed building. It generates its own power on-site from renewable sources, and can operate independently of the mains electricity grid. The building’s owner Grocon, Australia’s largest privately-owned development, construction and investment management company, wanted to create its own renewable electricity on site through biomass gasification, fuelled by wood chips and waste paper collected from the 50-storey office block. Legion House can run in ‘islanded mode’, operating fully from on-site power generation. The building’s location meant it was not able to rely on solar or wind for renewable power generation. Instead it uses two synchronised gas-fired generators connected to the stabilisation and storage system, which serve as a common power bus to provide a base electrical load, while the battery-based energy storage system dampens the effects of instantaneous load steps. The system exports spare electrical power to the adjacent tower building. The battery power system is also used to serve the overnight electrical load as well as minimise the generator operating hours. The microgrid’s stabilisation and battery-based energy storage systems ensure the tenants have continuous access to a reliable electricity supply. They stabilise the internal (islanded) power network against fluctuations in frequency and voltage that can be caused by essential building services such as elevators and air conditioning systems. The solution uses advanced control algorithms to manage real and reactive power that is rapidly injected or absorbed to control the power balance, voltage, frequency and general grid stability. The energy monitoring control system and battery monitoring system monitor and control the batteries to provide 100 kVA/80 kW power for up to four hours of electricity supply. The system monitors and controls various battery parameters, including battery temperature, to maximise service life, and it can also be remotely accessed. Backup power for ABB in South Africa ABB is itself installing an integrated solar–diesel microgrid at its Longmeadow premises in Johannesburg, South Africa. This will integrate multiple energy sources and battery-based stabilisation technology to ensure continuity of supply. ABB’s 96,000 m3 facility houses the company’s country headquarters, as well as medium-voltage switchgear manufacturing and protection panel assembly facilities. The microgrid solution includes a 750 kW rooftop solar photovoltaic (PV) array and 1 MVA/380 kWh battery- based grid stabiliser, which will help to maximise the use of clean solar energy and ensure uninterrupted power supply to keep the lights on and the factories running even in the event of a power outage on the main grid supply. Celine Mahieux is Research Area Manager: Innovative Applications and Electrification at ABB. Alexandre Oudalov is Senior Principal Scientist with ABB Corporate Research. www.abb.com This article is available on- line. Please visit www.cospp.com For more information, enter 8 at COSPP.hotims.com
  20. 20. Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com18 Steam recompression Steaming ahead S team recompression is an economically and energetically attractive technique. Steam is still a major energy carrier in all branches of the chemical industry. It can be used at several pressure and temperature levels. High-pressure steam is used to drive turbines while low- pressure steam delivers process heating. As soon as the steam pressure drops below 5 bar, it hardly has any value since the corresponding temperature of approximately 150oC is too low. However, efficient recompressing of this steam yields a valuable energy carrier: a waste product becomes useful. The process is called Mechanical Vapour Recompression (MVR). The thermodynamic principle MVR is an open heat pump system. Through compression, both pressure and temperature increase, together with the corresponding saturation temperature. The required compression energy is very small compared to the amount of latent heat present in the recycled steam. In the example in Figure 1, the added compressor energy is only 310 kJ per kg steam,whereas the latent heat of the compressed steam is 3060 kJ/kg. The process is illustrated by the solid red line. The system operates as a heat transformer that upgrades the quality of the heat in the steam. It is primarily the isentropic efficiency (approximately 75%) of the compression process that causes superheating of the steam. This superheating can be compensated by injecting boiler feed water so that the desired steam with MVR Mechanical vapour recompression (MVR) can improve energy efficiency in process plants and offers possibilities for integrating renewable electricity and demand side management,writes Egbert Klop
  21. 21. Steam recompression www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 19 temperature is created. One might state that the overheating of the steam is transformed into additional steam production. In the example shown in Figure 1, an additional 11% of steam is produced by injecting boiler feed water of 70oC. The trick of the process is avoiding condensation of the steam and retaining the latent heat. Figure 2 shows the schematic representation of steam recompression and water injection (de-superheating) based on two-stage compression. The knock-out drums and the demisters prevent erosive damage to the compressor blades caused by water drops. The recycle valve is needed for the startup process: the steam will be recycled until the desired condition has been reached. Energetic performance The energetic performance of MVR is commonly expressed in the coefficient of performance (COP), as is the case with standard heat pumps. The COP gives the ratio of the net recovered heat and the energy used by the compressor. In this case, the net heat is the steam production including the additional steam yield by water injection. Typical economical and energy-efficient applications have a minimum COP of 3.5. Some applications of MVR prove that a COP of 10 or even higher is achievable. Key elements for a high COP are: - A low ratio of the absolute steam pressures.A guideline for the maximum ratio is 6; in daily practice the ratio is about 3; - A minimum capacity. A guideline is a minimum of one tonne of steam per hour; - Water injection after compression. MVR is very effective in comparison with other techniques. Simple electrical heating yields a COP of only 1. Systems that turn hot water into steam by means of a heat pump are also being developed, but such systems are hardly available on the market yet. An interesting development in this context is the Radiax compressor from Bronswerk Heat Transfer. Available compressor technology For MVR, a wide range of compressors is available. The compressor type depends on the pressure and temperature ratios, the absolute pressure and the volume flow. Figure 3 gives an overview of the operating range of the available compressors, using atmospheric steam as the starting point. Benefits of steam recompression The technical and financial investment risks of MVR are low. MVR is primarily interesting for processes with a surplus of low-pressure or flash steam. Examples of the benefits are: - Payback periods between one and three years; - Reduced waste of energy; - Higher energy efficiency and less use of fossil fuel; - Flexibility in steam production; - High compressor capacity: up to 200 tonnes per hour; - Flexibility can be created by putting compression units in parallel; - Control of the power/heat ratio in case of combined heat and power; - Demand-Side Management depending on the electricity price. Systems are generally switched off at an electricity price exceeding €100 ($113)/MWh; - The possibility of using renewable electricity for the compression process; - Proven technology. Economic aspects MVR is always custom-made. The return on investment depends on the following factors: - The capacity of the installation; - The price of the output steam, which generally depends on the gas price; - The pressure ratio; - The value of the input‘waste’ steam; - The electricity price. A number of business cases have shown that MVR is ‘Bull gear’ multi-stage compressor Credit: Atlas Copco Efficient steam recompression yields a valuable energy carrier: a waste product becomes useful Credit: Atlas Copco
  22. 22. Steam recompression Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com20 economically quite robust. This is supported by extensive sensitivity analyses in which the electricity price, the value of the input steam, the value of the produced steam and the level of investment vary. At a ratio of three between the electricity price and the gas price per energy unit, the investment is still profitable, provided a good COP is present. Typical electricity prices for large industrial users are €50/MWh. In practice, it is not the electricity price but the capital expenditure for MVR and the price of natural gas that determine its economic viability. If renewable electricity is used, the carbon footprint is even reduced. Effect on the cogeneration sector High gas prices and low electricity prices in Europe are drastically limiting the economic possibilities of CHP. Existing installations are often stopped or mothballed. The flexible application of MVR means that excess electricity does not have to be dumped at low prices, but can be used. This reduces the occurrence of excessively low electricity prices that hamper the profitability of CHP.A continued use of CHP will help reduce fossil fuel consumption as well as greenhouse gas emissions. Social benefits of electrically-driven MVR Beyond the direct economic benefits for the user of MVR, there are a number of synergetic effects. The opportunity to use renewable electricity, especially in periods when production exceeds demand, is very welcome. Also, the combined heat and power (CHP) sector as well as the grid operator benefit from the possibilities of MVR. Policy measures in the EU have resulted in a large increase in variable electricity production from renewables. This means there will be an increase in the volatility of electricity production, mainly caused by the subsidies for renewables. MVR is an excellent tool for balancing based on Demand-Side Management. Co-operation between the different sectors is key to a more sustainable society. MVR is a major tool, provided it will be applied at a large scale in industry. Dutch research organisation ECN has predicted the perspective for MVR at an electric power of 2000 MW in the Netherlands.This compares with a thermal energy flow of around 20 GW. MVR case studies In the following three case studies, the technical and economical feasibility of steam recompression are shown. Cases one and two show the upgrading of steam for different capacities, while case three shows the use and upgrading of flash steam from condensate. The main conclusion from these cases is that steam recompression is a very economical way of improving energy efficiency, with a simple payback period between one and three years. It will be clear that a high number of annual running hours boosts profitability. Looking at the effect of the annual running hours on the economics of cases one and two,it is obvious that the Capex dominates the economic viability. Upgrading the steam Two cases have been evaluated: first, the almost continuous (8000 hours/ year) upgrading of 50 tonnes/ hour of steam (saturated) at a gauge pressure of 3.5 bar to 12 bar; and second, the upgrading of 10 tonnes/hour steam at a gauge pressure of 1.5 bar to 9 bar during 6000 hours/year. In both cases, there is no current application for low quality steam, and it therefore has no economic value at present. The steam is condensed, which even requires electric energy for the cooling fans of the condensers. This aspect has been neglected in the evaluation. In both cases,the steam has been compressed to a level that can be used in the process. Two-stage compression is required because of the high pressure ratio.Water is injected between the two stages to reduce overheating, and consequently to improve the efficiency.Figure 2. Steam recompression and water injection based on two-stage compression Source: Atlas Copco Figure 1. Pressure-enthalpy diagram for steam recompression with water injection Source: Industrial Energy Experts Recompression (compressor efficiency 75%) Recompression (compressor efficiency 100%) Water injection Thermal process Enthalpy
  23. 23. Steam recompression Owned & Produced by: Supported by:Presented by: SPEAKER OPPORTUNITIES NOW AVAILABLE CREATING POWER FOR SUSTAINABLE GROWTH CONFERENCE & EXHIBITION 19-21 JULY 2016 SANDTON CONVENTION CENTRE, JOHANNESBURG, SOUTH AFRICA Industry experts are invited the opportunity to be a speaker at POWER-GEN Africa & DistribuTECH Africa 2015, Africa’s leading power events which have quickly established an unrivalled reputation for delivering a joint world-class conference & exhibition. With as many as 221 strategic, technical, renewable and transmission & distribution topics to choose from, you have no shortage of material upon which to base your abstract. Don’t miss this opportunity to present your wealth of knowledge, ideas and experience to 2,000+ key players from around the globe. Supporting Association: www.powergenafrica.com www.distributechafrica.com SUBMIT YOUR ABSTRACT BY 6 JANUARY 2016 Case 1: • Steam flow: 50 tonnes/hour • Absolute input steam pressure: 4.5 bar • Absolute output steam pressure: 13 bar • Compressor power: 4.4 MW • COP: 9.8 • Running hours: 8000 hours/ year • Reference energy costs: 7600 k€/year • Energy costs MVR: 1760 k€/year • Cost reduction: 5840 k€/year • Capital investment: 5700 k€ • Simple payback period: one year Case 2: • Steam flow: 10 tonnes/hour • Absolute input steam pressure: 2.5 bar • Absolute output steam pressure: 10 bar • Compressor power: 1.1 MW • COP: 7.9 • Running hours: 6000 hours/ year • Reference energy costs: 1140 k€/year • Energy costs MVR: 330 k€/ year • Cost reduction: 810 k€/year • Capital investment: 2090 k€ • Simple payback period: 2.6 years Case 3: flash steam In this case, energy that is still available in intermediate- or high-pressure condensate is used. By reducing the condensate pressure, part of the condensate flashes to steam. In case 3, condensate of 8 bar is flashed at a pressure of 2.5 bar.This is then increased to 6 bar by MVR. • Condensate flow (absolute pressure 8 bar): 50 tonnes/ hour • Absolute flash pressure: 2.5 bar • Flash steam flow:3.2 tonnes/ hour • Compressor power: 257 kW • COP: 10.3 • Running hours: 8000 hours/ year • Reference energy costs: 486 k€/year • Energy costs MVR: 103k€/year • Cost reduction: 383 k€/year • Capital investment: 800 k€ • Simple payback period: 2.1 years Egbert Klop is Managing Director of Industrial Energy Experts www.ieexperts.nl This article is available on-line. Please visit www.cospp.com Figure 3. Functional ranges of compressors for vapour recompression Source: GEA Wiegand
  24. 24. CHP’s grid balancing capability Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com22 Grid balancing with district heating Energy management solutions can guarantee more economic CHP plant operation and allow plants to participate in the smarter business of balancing the grid, writes Juha-Pekka Jalkanen T oday’s energy systems have become increasingly complex because of two major challenges. Wind and solar, along with energy storage, pose the first challenge to the balance management of any energy- producing system. The second challenge is the continuous turbulence in electricity pricing. When wind is abundant, electricity prices drop radically to a very low level. The price changes also need to be considered at the plants as quickly as possible. Although district heat needs to be produced, a plant must assess how profitable electricity production is when selecting production units for district heat. Reaching optimal production is more demanding than ever, so plants need to plan better and forecast the future. They also must react more quickly to changes in the market, and produce more electricity at times when it is most profitable to do so. How can they know what the electricity price will be today? How much heat is needed? Additionally, how can they take care of process disturbances and be ready to participate in the intraday or reserve power market? Synchronising networks Combined heat and power (CHP) is used to produce electricity along with heat for industrial processes or heating. The main difference between the networks lies in the fact that the heat network operates locally with the CHP plant having active control over it, whereas the balance in the electricity network is controlled by the transmission system operator. Because day-ahead electricity prices are at the Finland’s Fortum Suomenoja combined heat and power plant Credit: Valmet
  25. 25. CHP’s grid balancing capability www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 23 level of a low-cost commodity, there may be more business motivation for participating in the regulating power market. The key is to find the right combination of controlling the heating network and participating in balancing the electricity network. This puts the CHP plant in a key role as a bridge to enable a smooth synchronisation of resources. In the end, the two networks should not only be sustainable, they must also be affordable and reliable. These goals can be achieved by a clever co-ordination of various players in the energy markets and a smart mix of energy sources – and the right tools to control the results. Novel concepts for sustainability FLEXe stands for building flexibility into energy systems. The FLEXe consortium aims to achieve a better energy system for the future.TEKES, the Finnish Funding Agency for Innovation, is funding the project.The goal is to enable companies to create novel technological and business concepts to ease the disruptive transition from the current energy system towards one that combines smartness, flexibility, environmental performance and economic success. The consortium consists of 17 companies and 10 research institutes or universities in Finland. Thanks to a broad spectrum of competencies, FLEXe covers the whole energy system value chain. As the only company in the programme that concentrates on advanced plant-level and district heating network controls, Valmet’s role is to study how to support system- level flexibility by means of advanced controls. The target is to get information from different business models to understand future developing needs. This will enable Valmet to create a path for companies to migrate to new systems. Valmet will specifically study the optimal operation and control strategies of power plants and heat networks in this new and flexible operational environment. Plan, optimise, control To enable CHP plants to plan and forecast more effectively as well as become more proactive, the Valmet DNA Energy Management platform allows plants to plan their energy production in the most optimal way. In addition, energy management controls, information sharing and updated production plans give plants the quick reaction ability they need. Valmet DNA Energy Management is a modular energy management system, delivered in collaboration with partner Energy Opticon Ab in Sweden. The system forecasts district heat demand and optimises production, allowing units to achieve the best total economic costs and to determine the optimal times for unit startups and shutdowns. A common user interface for all personnel improves communication. Thanks to a uniform way of planning, fewer human errors occur. Valmet DNA Steam Network Manager and Valmet DNA District Heating Manager are part of the energy management controls. Costs are minimised because disturbances can be corrected quickly, and power generation can be maximised by keeping plant availability as high as possible. A holistic approach for district heating Fortum’s Suomenoja CHP plant in Finland produces heat for households in the greater Espoo region, and electricity for the national grid. Its large and complex network consists of multiple units. The power plant produces about 1800 GWh of electricity and 2200 GWh of district heat per year. Suomenoja is the first power plant in Finland to optimise its district heating network using the DNA District Heating Manager solution, which is based on multivariable model predictive control. Until the optimisation, operating conditions in the plant’s district heating network were maintained manually, and operators had to run the network with more heat than necessary. At the same time, constant temperature and pressure fluctuations at the plant posed risks for severe disturbances. The goal was to provide Suomenoja with both economic and environmental benefits through better control of its network. Better control of temperature and pressure fluctuations in the heat plant minimises heat stress to the district heat piping, and is thus one tool to avoid severe disturbances. Better control of the pressure difference throughout the network also eliminates the need to produce any additional heat, resulting in higher energy efficiency. The DNA District Heating Manager keeps heat production and consumption accurately balanced throughout the whole network. The CHP, heat-only units and pumping stations are all controlled by a single controller, which takes into account the dynamic interconnections of all controlled units. The co-ordinated control of all production units and pumping stations allows heat loads to be transferred from one area to another with flexible allocation of heat loads between production units. Accurate control improves heat delivery efficiency by decreasing the heat losses in the network. While the heat production of the CHP units varies according to electricity prices, or they participate in the balance control of the electricity grid frequency, the heat-only stations keep the entire district heating network stabilised.This allows all units to be run at economically optimised loads and enables a fast response to unexpected disturbances, heat demand changes, electricity prices and grid balance actions. Ultimately, all improvements contribute to the reduction Realised ELSPOT price and power Forecasted ELBAS and regulating power prices Unit availabilities Current loads DH load forecast Natural Gas forecasts (price and availability) Optimal loads for units + Deviation from optimum loads Optimisation (plant model, other fuel prices) Intraday production planning at Tampereen Sähkölaitos in Finland. Optimisation enables calculating the weekly production forecast and the day-ahead production plan. Source: Valmet
  26. 26. CHP’s grid balancing capability Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com24 of fuel consumption and CO2 emissions, making CHP production an even more environmentally friendly and economical form of heating. Optimisation and forecasting Tampereen Sähkölaitos Group, based in Tampere, Finland, is a regional operator in energy with approximately 130,000 customers. The 120-year-old group provides electricity, district heating, district cooling and natural gas. In 2014, Tampereen Sähkölaitos Group chose Valmet as a supplier for the production optimisation system for the entireTampereen Sähkölaitos. The system features district heat demand forecasting and production optimisation of all five power plants and peak heat centres. ‘Our three main reasons for implementing the production optimisation system at Tampereen Sähkölaitos were to help the electricity traders plan the production, to improve communication between the traders and the control room, and to allow the use of the same optimisation model for long-term production optimisation – and even for budgeting,’ says Marko Ketola, Senior Specialist at Tampereen Sähkölaitos. An accurate forecast of the district heat demand forms the basis for decisions. Optimisation enables calculating the weekly production forecast and the day-ahead production plan to support electricity trading and the intraday production plan. The traders who work 24/7 make the plan for production. Due to the lower electricity prices, the production environment has become more complex. For instance, bypassing the turbine is used more often.Therefore, it is more difficult to manually optimise and plan production. ‘In addition to their expertise, traders now have the tools for making the production plan. This reduces errors and improves the planning accuracy,’ Ketola says. The production optimisation system is integrated within the automation and information systems of the company and individual plants, and is connected to Tampereen Sähkölaitos’s financial system. Therefore the current production and consumption rates, availability of the production units, electricity purchase data and fuel prices can be used to quickly update the production plan, whenever there are changes in the market and process environment. Thus, even electricity market changes are reflected in the latest optimal production plan. Tightintegrationalsoensures that the communication between control rooms and traders is improved.The current plan, and any deviation from it, are shown in the operator’s interface in the control system. Communication is also important, according to Marko Ketola. ‘Earlier, this was mainly based on phone calls. Now, there is a common user interface that displays the plan and the reasons behind the plan. There’s a common basis to discuss and from which to make production decisions,’ he says. The system does not remove the need to talk, but it enhances transparency and thereby production efficiency. Integration with the control system makes it possible to use the district heat demand forecast and the optimal production plan to control production. Over the long term, systematically collecting history and monitoring information on forecasts, plans, actual production and deviations from the plan enable Tampereen Sähkölaitos to economically follow up its energy production.This means that it is possible to decrease production costs for district heat and increase profits from electricity production. The upside of being in balance With the use of energy management and controls for district heating networks, it is possible for a plant to play an active role in improving the overall production economy and ultimately balancing the grid. Short-term benefits include using the same planning principles for each shift, minimising the chance for human error and eliminating differences in running the plant. Also, when the day-ahead electricity is planned and communicated to everyone, the controls can support the plant in keeping the target. Additionally, a CHP plant can capitalise on the potential offered through electricity trading. With changes in the market, weather or process, it is possible to quickly calculate and utilise a new production plan for the current day or the following hours. This allows plants to participate in the short-term market. In all, it makes sound business sense for a CHP plant to proactively participate in balancing the electricity grid, not only on the day-ahead and intraday markets, but also as a frequency-controlled power reserve. CHP plants that take advantage of advanced energy management solutions and district heating controls can decrease the production costs of heat and maximise profits from electricity sales. This makes production within complex networks easier to plan, optimise and control. In turn, CHP plants can take a more profitable role in the future’s sustainable, reliable, flexible and affordable energy system. Juha-Pekka Jalkanen is Director, Power Automation Solutions at Valmet. www.valmet.com This article is available on-line. Please visit www.cospp.com District heating network Heat storages Electricity storage Conven- tional producers Solar power Process steam demand Wind power Heat- only-boilers Pumping stations Geothermal heat Electrical network Consumers & Prosumers CHP plants Link between grid and heat network The key is to find the right combination of controlling the heating network and participating in balancing the electricity network. This puts the CHP plant in a key role. Source: Valmet
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  28. 28. Operations & maintenance Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com26 Big data and intelligent maintenance Data-based prognostic technology can determine the future condition of machines, laying the foundation for intelligent maintenance planning, writes Moritz von Plate T he world’s energy needs are constantly growing. Worldwide population growth and the continuing industrialisation of emerging economies, notably China and India, are the major causes for this growth in energy consumption, which has a negative impact on the environment. According to the Intergovernmental Panel on Climate Change (IPCC), anthropogenic greenhouse gas emissions, i.e., emissions caused by human activity, have increased significantly since pre-industrial times and are currently at an all-time high. Green technologies, such as cogeneration plants, have therefore become increasingly relevant for energy production and will become even more relevant in the future. Thanks to the new technologies of the Internet of Things, it is now possible to perform cost-effective maintenance measures that can increase security and prevent unplanned outages in cogeneration plants. Such new technologies make it possible to analyse process and condition data of plants and make prognoses of the system’s future state. In addition, these prognoses change the way in which people make decisions. The role of data The industry is offered totally new possibilities through the Internet of Things, especially when it comes to process optimisation and automation. The way has been paved for profound changes to industrial processes by implementing modern information technologies. In the course of advanced digitalisation, machines are linked with one another and collected data is used to intelligently co-ordinate and improve processes. When it comes to maintenance and operational management, Big Data technologies enable a data-based and future- oriented prognostic strategy. For example, thanks to innovative Big Data technologies, prognoses on the future condition of a machine or its individual components can be created. With a prognostic approach, users receive a data-based prognosis and can adjust maintenance plans accordingly. Further, unnecessary costs or unplanned outages can be avoided, for example by replacing parts in time, i.e., not too early and not too late. In this context, prognostics can be defined as an ‘objective and data-based forecast of future conditions with an explicit time reference’. In practical terms, this means that prognostic reports can provide information on the future condition of machines or machine components for a period of mostly weeks or months or, in special cases, even years. Predictive diagnostics vs prognostics This prognostic approach is not synonymous with the so-called Predictive Diagnostics or Predictive Analytics. Predictive Diagnostics recognises initial early warning indicators for future malfunctions by means of data abnormalities, and provides diagnostic findings about the current condition.Yet it does not provide information on when an abnormality will turn into a malfunction, i.e., when the time frame until the next malfunction arises will close (tomorrow, in a week, or is it still months?). Prognostics, on the other hand, not only reports on when one can expect a malfunction, but also indicates when the time frame during which measures can be taken will close. Because the prognoses are calculated for each machine individually,they are not based on average data from other machines or manufacturers’ specifications. This has the advantage that the individual performance curves, the operational strategy and, if applicable, previous data on historical incidents is included in the prognoses. This results
  29. 29. Operations & maintenance www.cospp.com Cogeneration & On–Site Power Production | November - December 2015 27 in the prognoses reaching a higher level of precision and reliability. When calculating prognoses, the historical data runs through a number of different steps. These consist of stochastic methods and include highly developed algorithms. The result is an explicit future risk profile that illustrates the probability of malfunctions over time. The requirement for a prognosis is to collect and store enough process data (e.g., rotation frequency, speed, temperature and pressure) and condition data (e.g., vibration data, lubrication data and housing temperature). An ideal time frame of data history is three to five years, whereby it is possible to complete a reliable prognosis with a shorter time- frame.The storage format does not play an important role. It is more important to ensure that the data is as complete as it can be,as this will increase the validity of the statistics. Condition-based maintenance Instead of relying on fixed maintenance intervals or waiting for something to break, the information from a prognostic report can be used to ensure that maintenance and repair work can be carried out when needed. Parts will not be replaced too early on speculation, but rather when it is necessary from a technical point of view. Apart from this, by means of the prognostic reports and good data processing, it is also possible to recognise the effect that various operational scenarios will have on the equipment’s remaining useful life (RUL), transparently and objectively. By doing so, the RUL can be actively managed through adjusting the operational mode. How the installation works Introducing transparency into the RUL and, ideally, being able to actively control it were the aims of a project in which Cassantec implemented the solution in a fossil fuel- fired power plant. The active management of the RUL should take place in such a way that the duration of the RUL and the operational mode are balanced to achieve the desired outcome. Additionally, maintenance activities should be optimised to lower the operational and repair costs. Such a project is divided into two phases. As a prerequisite, historical available condition and process data from the power plant must be collected and prepared for further processing. During the first phase – the so-called configuration phase – the power plant experts and Cassantec ascertain the correlations between data parameters and specific malfunctions. The second phase is prepared based on this foundation: the actual calculation and prognoses of the risk of malfunctions. This phase also includes the fine-tuning of the preliminary component specific warning and alarm levels. How the solution works at a cogeneration plant The first prognostic reports compiled for a cogeneration plant have already delivered valuable findings for the operator. For example, by implementing a scenario analysis which determines the dependence of the data on the operational regime, it is possible to find a new and optimised mode of operation for the equipment. This can have a positive effect on the RUL of the equipment, its reliability and the need for maintenance. Based on results produced by the prognostic solution, the energy provider receives valuable insight into the relationship between operational strategy and the RUL of the power plant and, in particular, the critical equipment. This goes much further than the information available from conventional condition monitoring and diagnosis.Theresultsenablethe operator to make well-founded decisions on the adjustment of his or her operation and maintenance plan for the An illustrative excerpt from a prognostic report for one example generator Source: Cassantec The colour green represents a low risk of malfunction Source: Cassantec
  30. 30. Operations & maintenance Cogeneration & On–Site Power Production | November - December 2015 www.cospp.com28 critical equipment, in order to be able to optimise its usage in three fundamental aspects: considerable extension of the RUL, minimising maintenance costs through optimisation of the maintenance plan, and specific information on when a component will need to be replaced. When the operator decides to expand the implementation of the prognostic solution to other similar plants in the fleet, the configuration phase, as outlined above, is significantly shortened. In addition, the operator can expect extensive savings in maintenance and repairs, and a comprehensive understanding of the condition of the machinery and of the factors that influence the RUL. Fleet-wide implementation also leads to a fleet-wide learning effect that boosts the initial advantages. How people will make decisions in the future Whether consciously or unconsciously, humans make hundreds of choices every day. Gerhard Roth, a professor at the Institute for Brain Research in Bremen, has determined that, quite often, gut decisions are the better choice. When choosing what to eat for breakfast or what to wear, that is perhaps the best way; however, for more complex decisions the basis should not be intuitive. Especially when the cause and effect of a problem are not clear and decision-makers are faced with complex structures, data- based facts can put them on the right track. Algorithms help people solve complex problems such as the maintenance of equipment, and help them make better judgments. At present, the basis for making many decisions is still often experience or intuition. Humans have their own ‘computer’, the brain. However, the brain is not immune to prejudice. Even factors such as the weather or one’s mood demonstrably and significantly influence decisions. Often many important characteristics are lacking for a proper analysis and assessment, but an algorithm that is programmed in advance is subject to fewer such errors in reasoning. Mathematical foundations offer the possibility that decision-makers receive a formula that is objective, transparent and applicable to different situations. Thus, for example, through the use of Cassantec’s prognostic reports, a foundation is created to make sound decisions for maintenance strategies – for example,to pool maintenance interventions intelligently and to plan them in time to avoid costly overtime and night shifts. Maintenance plans will no longer be created periodically and based on experience, but with a transparent,data-based structure.This saves companies huge costs. What is holding us back Society is at the beginning of a digital transformation. Industry 4.0 and the Internet of Things offer enormous potential to change and exercise a positive influence over the way employees work. Yet technologies such as prognostics also face challenges. The prudent application of prognostic solutions requires that reliability and maintenance professionals possess an extended skillset: the ability to articulate risk, to explicate forecasts, and to consider both in asset management decisions. Prognostics complements and requires operator experience and manufacturer know-how, but it also necessitates a shift in thinking and language towards a risk management approach. In the long run, though, it is clear that companies and professionals must face these challenges. Companies that have not already started collecting data for sophisticated analyses,and that are not planning to make use of the new possibilities, will eventually reach the point where they can no longer compete in the digitalised environment. The foundation for intelligent planning The use of complex data analytics in order to control and improve processes is increasing in the age of Big Data and the Internet of Things. When it comes to maintenance and repair activities, the use of big data analytics is likewise increasing. With the help of data-based prognostic technology, the future condition of machines can be determined. This creates the foundation for intelligent maintenance planning. Instead of fixed intervals, maintenance will now only take place when it is technically necessary. Implementation in a cogeneration plant can increase the understanding and transparency for the plant. The foresight derived from prognostics can enable an active control and expansion of the RUL. Moritz von Plate is CEO of Cassantec www.cassantec.com This article is available on-line. Please visit www.cospp.com Advantages of prognostics: • Maintenance can be carried out when it is technically necessary, which reduces the number of maintenance interventions; • The influence of the operational regime on the RUL becomes transparent,which means that it is possible to actively manage RUL; • It becomes apparent well in advance when the risk of a malfunction will reach the risk tolerance threshold. This allows for avoidance of unplanned malfunctions; • Repairs can be planned in advance and then conducted when the impact of operational interruptions is at its lowest; • The processing and presentation of the data provides transparency and enables fleet-wide comparisons over time; • Decision-making competency can be increased by means of objective information, the machine will gain in safety and reliability, and the reduction of (unplanned) malfunctions will save budget. The dots show the exact data reading points Source: Cassantec