3. • Literature
– Taylor, G., Tanton, T. 2012. The hidden cost
of wind electricity. American tradition institute.
http://www.atinstitute.org/wp-content/uploads/2012/12/Hidden-Cost.pdf
– Hirth, L. 2013. The optimal share of variable
renewables. How the variabiity of wind and
solar power affects their welfare-optimizing
deployment. FEEM Working Paper 90.2013.
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2351754
– Kirchen. Chapter 1
5. The technology behind crystalline
silicon solar cells has profited from
extensive developments in the multi-
billion-dollar microelectronics
industry.
About 20 years ago, a kilowatt of
solar energy cost about 50 euro
cents ($0.69) to produce, today in
Germany it's about 10 euro cents -
while in sunny regions it's between
5 and 8 euro cents.
So worldwide, we're totally
competitive with, and often even
cheaper than, fossil fuels.
http://www.dw.de/at-the-floodgates-of-a-solar-energy-boom/a-17259267
Professor Eicke R. Weber is
the Director of the
Fraunhofer Institute for Solar
Energy Systems ISE and
professor of physics/solar
energy at the Department of
Mathematics and Physics
and the Department of
Engineering respectively at
the University of Freiburg,
Germany.
http://www.ise.fraunhofer.de/en/about-us/director-and-division-direc
Can this be true?
Why give subsidies still?
14. • Wind and solar should better be seen as:
– Wind and solar + gas backup (round 90%)
– Wind and solar + coal backup (round 90%)
15. • Taylor, G., Tanton, T. 2012. The hidden
cost of wind electricity. American tradition
institute. http://www.atinstitute.org/wp-
content/uploads/2012/12/Hidden-Cost.pdf
21. • This report has shown that the cost wind
electricity is not approaching parity with
conventional sources, and is unlikely to
reach parity
– unless the price of natural gas, the price of
coal and the capital cost of nuclear facilities
were all to increase dramatically.
22. • Study applies to US
– 3% of energy generated by wind
• Germany
– Has higher wind penetration
– 7~8% of energy generated by wind
• What is the effect of an increase in wind
penetration on costs?
23. 2. Model the value of electricity produced
by intermittent generation
24. • Hirth, L. 2013. The optimal share of
variable renewables. How the variabiity of
wind and solar power affects their welfare-
optimizing deployment. FEEM Working
Paper 90.2013.
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2351754
28. • We define profile costs as the price spread between the load-
weighted and wind-weighted day-ahead electricity price for all hours
during one year. Profile costs arise because of two reasons. On the
one hand, demand and VRE generation are often (positively or
negatively) correlated. A positive correlation, for example the
seasonal correlation of winds with demand in Western Europe,
increases the value of wind power, leading to negative profile costs.
• On the other hand, at significant installed capacity, wind
“cannibalizes” itself because the extra electricity supply depresses
the market price whenever wind is blowing. In other words, the price
for electricity is low during windy hours when most wind power is
generated. Fundamentally, profile costs exist because electricity
storage is costly, recall physical constraint i). A discussion of profile
costs and quantitative estimates are provided by Lamont (2008),
Borenstein (2008), Joskow (2011), Mills & Wiser (2012), Nicolosi
(2012), Hirth (2013), and Schmalensee (2013).
29. • wind “cannibalizes” itself because the
extra electricity supply depresses the
market price whenever wind is blowing
34. • Profile cost: wind produces most when the price is low
• Balancing cost: forecasting errors
– wind produces is “out-of-balance”, produces more or less than
promised
– Cycling costs of plants
35. • Profile cost: wind produces most when the price is low
• Balancing cost: forecasting errors
– wind produces is “out-of-balance”, produces more or less than promised
– Cycling costs of plants
36. European Climate
Foundation 2050:
• Increase from 34
GW to 127 GW
• 400% increase
The future of the EU transmission network
Authors wont model the
losses due to location
(grid costs) were not
modeled
37. • Profile cost: wind produces most when the price is low
• Balancing cost: forecasting errors
– wind produces is “out-of-balance”, produces more or less than promised
– Cycling costs of plants
• Grid costs: wind produces far away from demand
– Cost of additional transmission
38. • Cost change with penetration
(cannabilization effect)
39.
40.
41. • So far are theoretical models, what do the
numbers tell us?
– Use of a dispatch model, feeding realistic data
– Northwestern Europe: Germany, Belgium,
Poland, The Netherlands, and France
44. If wind blew constantly
If wind was variable but
perfectly predictable
True situation
Note that losses due to
location (grid costs)
were not modeled
LCoE use the simplification that wind blows constantly.
This simplification seems to explains the wide gap in the debate on
the usefulness of wind.
46. • What is remarkable about this curve?
• Optimal wind share with doubling of:
– Coal price -> increases
– Gas price -> decreases
47. • Doubling coal prices -> optimal wind up by
5% points
• Halving gas prices (“shale gas”) -> optimal
wind down
• Doubling gas prices -> optimal wind down.
48. • Doubling coal prices -> optimal wind up by 5%
pointsfive percentage points (Figure 17).
• Lowering gas prices by half (“shale gas”) has a
similarly expected effect,dramatically lowering
optimal wind deployment.
• Surprisingly however, doubling gas prices
reduces the optimal wind share.
– As in the case of CO2 pricing, the reason for this
seemingly counterintuitive result can be found in the
capital stock response to the price shock. Higher gas
prices induce investments in hard coal, which has
lower variable costs, reducing the value of wind power
and its optimal deployment.
49. Solar
• Even at 60% cost reduction, the optimal solar share is
below 4% in all but very few cases.
• Reason: the marginal value of solar power drops steeply
with penetration,
– Even more so than wind. Why?
– Because solar radiation is concentrated in few hours
• In line with earlier studies (Nicolosi 2012, Mills & Wiser
2012, Hirth 2013).
Now: €1-2/W
Hirth + 60% cost reduction:€0.6/WHirth uses€1.6/W
56. • Coal supplies more than 5 percent of
energy
– 1840
• fossil fuels (coal) surpasses use of
biomass (wood and charcoal)
– 1885 USA
– 1875 France
– 1901 Japan
– 1930 U.S.S.R
– 1965 China
– 1970 India
57. • Oil supplies more than 5 percent of energy
– 1915
• Oil surpasses use coal
– 1964
84. A:40M
W
A
B
Injection: 120MW
30$/MWh
С
Limit: 500MW
Limit: 20MW
70$/MWh
A:80M
W
A: 40MW
Solution 3:
Counter flow &
proportional
downturning
Inject 60 MWB:20M
W
B:20M
W
B: 40MW
Injection: 80MW
30$/MWh
A:53.33
M
W
A:26.67M
W
A: 26.67 MW
Inject 40 MW
B:13.33M
W
B:13.33M
W
B: 26.67 MW
Demand: 120MW
Withdrawal: 180MW120MW
92. Peak-load pricing
Gives clear economic signals!
ST-MC
Off-peak
Peak
LT-MC
Ppeak
POff-peak=0
92
ST-MC
Off-peak
Peak
LT-MC
Ppeak
POff-peak=0
Invest in expansion
of transmission
capacity on the line
Do not invest in expansion
(wait or even remove a line)
Figure 2: From the average electricity price to wind’s market value (illustrative). At high penetration, timing and location as well as forecast errors typically reduce the market value
Figure 2: From the average electricity price to wind’s market value (illustrative). At high penetration, timing and location as well as forecast errors typically reduce the market value
• This graph from Aptech Engineering Services shows the different types of
load cycles (megawatts versus time) that a unit could be exposed to and
the relative damage that occurs each cycle.
• Three different low load cycling points LL1, LL2 and LL3 are defined on
this slide. Each point affects the degree of thermal cycle transient
experienced during a load following event because the metal incurs larger
temperature changes.
• Three on/off cycles are defined based on hours off-line (hot, warm and cold
starts) with the worst damage occurring during a cold start cycle.
• Definition of Equivalent Hot Start – Standardized in a 1985 EPRI study of
Haynes Unit 5 (Supercritical 350 MW unit)
• Load follows each have relatively low damage costs but because there are
so manyof them, the cumulative impact of manyload follows leads to the ypy damage of an equivalent hot start.
Figure 2: From the average electricity price to wind’s market value (illustrative). At high penetration, timing and location as well as forecast errors typically reduce the market value
Figure 2: From the average electricity price to wind’s market value (illustrative). At high penetration, timing and location as well as forecast errors typically reduce the market value
Figure 2: From the average electricity price to wind’s market value (illustrative). At high penetration, timing and location as well as forecast errors typically reduce the market value
Figure 3: Average electricity price and market value as a function of the quantity of wind power in the system. At low penetration, the wind market value can be higher than the average power price, because of positive correlation between generation and load.
Figure 6: Wind’s market value falls with penetration. The intersection between LEC and market value gives the optimal share (section 2.4). At LEC of 68 €/MWh the optimal share is around 3%; if generation costs fall by 30%, the optimal share is about 20%.
Figure 7: The optimal share of wind power in total electricity consumption as function of wind power cost reduction under benchmark assumptions. In Northwestern Europe, the share increases from 2% to 20%
If wind generation was constant, its optimal share would rise above 60%. The impact of forecast errors is much smaller: switching off the reserve requirement and balancing costs increases the optimal share by only eight percentage points. This endorses previous findings that temporal variability is significantly more important for welfare analysis than uncertainty-driven balancing
Figure 17: The effect of fuel price shocks. As expected,
lower gas prices reduce and higher coal prices increase the
optimal wind share. However, higher gas prices reduce the optimal share. The reason is the investments in baseload
technologies triggered by high gas prices.