Capacity Value - NREL

Western Wind and Solar Integra0on Study Phase 2 – Capacity Value Results TRC Mee0ng Eduardo Ibanez, Michael Milligan November 28, 2012 NREL is a na*onal laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

Tool: REPRA • Renewable Energy Probabilis0c Resource Assessment tool (REPRA) • Tool objec0ves o Include variable genera*on in tradi*onal probabilis*c-­‐based methods o Allow comparison of alterna*ve targets, metrics (LOLE, ENS, LOLH, etc.) • U0lized to quan0fy the capacity value of wind and PV 2

REPRA – Conven0onal Generators • A convolu0on is performed for conven0onal genera0ons • For example, six 50-­‐MW units with 8% EFOR result in the following convolu0on table MW-OUT MW-IN Probability LOLP0 300 0.6064 1.000050 250 0.3164 0.3936100 200 0.0688 0.0773150 150 0.0080 0.0085200 100 5.20E-04 5.38E-04250 50 1.81E-05 1.84E-05300 0 2.62E-07 2.62E-073

REPRA – Renewables • Renewables are represented using a sliding window approach MW-OUT MW-IN Probability LOLP0 100 0.4 1.010 90 0.4 0.620 80 0.2 0.24

REPRA – Combining Both MW-OUT MW-IN Probability LOLP0 300 0.6064 1.000050 250 0.3164 0.3936100 200 0.0688 0.0773150 150 0.0080 0.0085200 100 5.20E-04 5.38E-04250 50 1.81E-05 1.84E-05300 0 2.62E-07 2.62E-07MW-OUT MW-IN Probability LOLP0 100 0.4 1.010 90 0.4 0.620 80 0.2 0.2MW-OUT MW-IN Probability LOLP0 400 0.243 1.00010 390 0.243 0.75720 380 0.121 0.51550 350 0.127 0.39460 340 0.127 0.26770 330 0.0633 0.141100 300 0.0275 0.077110 290 0.0275 0.050120 280 0.0138 0.022150 250 0.0032 0.008160 240 0.0032 0.005170 230 0.0016 0.0025

ELCC: Measure Contribu0on of Generator to Resource Adequacy Loss of Load Expectation (days/year)0.120.110.100.090.080.070.06Original Reliability CurveReliability Curve after Adding New GenerationTarget Reliability LevelEach generator added to the systemhelps increase the load that can besupplied at all reliability levelsG iG i+1G i+2Added GeneratorsG n-2CombinedResourcesWithWind8.08.59.09.5Load (GW)10.010.511.0x10 36

Area Reliability • To calculate the ELCC in an area, load is scaled to meet a predefined criteria o E.g., 1 day/10 yrs LOLE o We will explore other values and metrics • Example, interpola0on steps to reach 1 day/10 yrs for the Western Electricity Coordina0ng Council Resul0ng LOLE 10 0.1 0.01 0.001 0.0001 It. 2 1 1.02 1.04 1.06 1.08 1.1 1.12 1.14 It. 3 It. 4… It. 1 Load Mul0plier 7

Variable Genera0on Capacity Value • We can compare the ELCC contribu0on of renewables combined and independently (assuming copper sheet) 35 70 30 60 Capacity value (GW) 25 20 15 10 Capacity value (%) 50 40 30 20 Wind PV Combined VG 5 10 0 TEPPC HiWind HiMix HiSolar 0 TEPPC HiWind HiMix HiSolar 8

Capacity value vs. installed capacity 30 70 25 60 Capacity value (GW) 20 15 10 Capacity value (%) 50 40 30 20 Wind PV 5 10 0 0 20 40 60 80 100 Capacity (GW) 0 0 20 40 60 80 100 Capacity (GW) 9

Other related work • E. Ibanez, and M. Milligan, “A Reliability-­‐Based Assessment of Transmission Impacts in Systems with Wind Energy,” Proc. of AWEA Windpower 2012, Atlanta, Georgia, Jun. 2012. • E. Ibanez, and M. Milligan, “Impact of Transmission on Resource Adequacy in Systems with Wind and Solar Power,” Proc. of IEEE PES General Mee:ng 2012, San Diego, California, Jul. 2008. • E. Ibanez, and M. Milligan, “A Probabilis0c Approach to Quan0fying the Contribu0on of Variable Genera0on and Transmission to System Reliabilty,” Proc. of 11th Int. Workshop on Large-­‐Scale Integra:on of Wind Power into Power Systems, Lisbon, Portugal, Nov. 2011. 10