Briefing on the duck curve and current system conditions Clyde Loutan, Senior Advisor Market Surveillance Committee Meeting General Session July 15, 215
Original estimate of net-load as more renewables are integrated into the grid Typical Spring Day Net Load 14,16 MW on April 5, 215 at 15:46 Slide 2
Negative energy prices indicating over-generation risk start to appear in the middle of the day # of Occurrences RTD Prices < Zero 16 14 12 1 8 6 4 2 Distribution of Negative Prices - March, April & May 212, 213, 214 & 215 Increasing real-time negative energy price frequency indicates overgeneration risk in the middle of the day 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 24 212 213 214 215 Slide 3
Average hourly hydro production for high, low and average hydro years --- April 7, 6,5 6, 5,5 25 - Normal 26 - High 27 - Dry 214-3 rd year Drought 215-4 th year Drought Average Hourly Hydro Production --- April 5, 4,5 4, MW 3,5 3, 2,5 2, 1,5 1, 5 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 24 25 3,759 3,598 3,466 3,419 3,47 3,686 3,651 4,65 4,31 4,543 4,69 4,747 4,774 4,826 4,744 4,67 4,565 4,523 4,635 4,988 5,246 4,769 4,445 4,97 26 5,479 5,471 5,347 5,295 5,378 5,439 5,625 5,84 6, 6,18 6,287 6,288 6,234 6,248 6,12 6,52 5,965 5,939 6,45 6,478 6,62 6,223 6,68 5,729 27 1,579 1,4 1,312 1,282 1,357 1,725 2,116 2,449 2,672 2,962 3,173 3,32 3,297 3,358 3,29 3,151 2,952 2,886 2,838 3,549 3,82 3,83 2,45 1,918 214 1,11 999 96 95 1,38 1,171 1,627 1,797 1,725 1,653 1,597 1,622 1,6 1,662 1,697 1,759 1,841 2,18 2,431 2,856 2,974 2,53 1,81 1,343 215 724 649 61 587 643 857 1,44 1,476 1,112 856 757 651 582 591 655 712 899 1,223 1,777 2,29 2,346 2,121 1,528 1,32 Slide 4
The assessment of a Balancing Authority control performance is based on three components Control Performance Standard (CPS1) - measures how well a BA s ACE performs in conjunction with the frequency error of the Interconnection measured as a 12 month rolling average Balancing Authority Ace Limit (BAAL) - is a real-time measure of area control error and system frequency which cannot exceed predefined limits for more than 3-minutes Disturbance Control Standard (DCS) - is the responsibility of a BA to recover its ACE to zero if its ACE just prior to the disturbance was greater than zero or to its pre-disturbance level if ACE was less than zero within 15 minutes New NERC operating standard (BAL-3-1 to be implemented in 217) All BAs to support the interconnection frequency within 3 seconds following a disturbance greater than 5 MW anywhere in the interconnection Control Performance Assessment Pass is when CPS1 1%; BAAL Limit 3 minutes & DCS = 1% Slide 5
Minimum on-line generation expected in a normal hydro year 34, Minimum on-line resources expected in a normal hydro year 32, 3, 28, 26, 24, 22, 2, MW 18, 16, 14, 12, 1, 8, 6, 4, 2, 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 24 Nuclear Non_Dis_QF Geothermal Biomas Biogas Normal_Hydro Reg_Down Min_CCYC_Prod LF_Down Net_Load Min_Net_Load Max_Net_Load Slide 6
Assumptions for base-loaded/non-dispatchable resources and minimum system reliability needs Base Load & Non-Dispatchable Resources RPS Diablo 1 & 2: Non-dispatchable QFs: Geothermal Biomas BioGas Small Hydro Total Non-dispatchable resources 2,243 MW 1,9 MW 88 MW 32 MW 19 MW 25 MW 5,783 MW Based on actual hourly average production for March 215 Reliability Needs from non-hydro resources Regulation Down 6 MW Load-following Down (varies by hour 3/215 actual needs) 2, MW Pmin of CCYC providing Frequency Response (4,844 *.33%) 1,6 MW Minimum Generation on CCYC Resources 4,2 MW Approx. 4,844 MW* of capacity on CCYC is needed to provide about 387.5 MW of frequency response within 3 sec. (i.e. 387.5 /.8 = 4,844) Minimum Hydro for Dry Year (Avg. HE7 to HE16) 3, MW Other Assumptions - Hydro resources can provide contingency reserve, regulation up and load-following and 5% of the ISO s Frequency Response Obligation (FRO) - No generation requirement for local constraints - Zero net imports (assumes the ISO can export approximately 3,6 MW of dedicated dynamic imports i.e. Palo Verde, Hoover, MUNI imports from LADWP and Geothermal from IID) *WECC FRO is 97 MW/.1 Hz of which the ISO s share is about 3% or 272 MW/.1 Hz. This equates to about 775 MW based on the loss of two Palo Verde units. Typically, a conventional resource on governor control can provide about 5% to 1% of its Pmax as FR within 3 seconds. Assume CCYC resources can provide 8% of Frequency Response. CCYC Combined Cycle Slide 7
Typical frequency Classic response Frequency recovery Excursion and potential Recovery need for ancillary services or capacity products Source: NERC Slide 8
As the grid transforms, existing ancillary service markets may not ensure the right resources with the right capabilities are available at the right time from all possible sources Traditional Ancillary Services Inertia Frequency Response Fast Frequency Response Primary Frequency Response Regulation Contingency Reserve Operating Reserve Spinning (Replaced Spinning Reserve in WECC) Non Spinning Reserve Flexible Resources (dispatchable conventional resources including VERs, energy storage devices and dispatchable loads). Attributes include but not limited to: Fast Ramping capability for defined periods Change ramp direction quickly Store energy or modify use Multiple Stop/Start Capability Low Pmin Slide 9
RPS Curtailment in 224 4% RPS Scenario Solutions Retrofit existing power plants Enable economic dispatch of renewables Decarbonize transportation fuels Increase storage and demand response Align time-of-use rates with system conditions Deeper Regional Coordination (EIM) Targeted Energy Efficiency Slide 1
5-Minute energy price distribution for Jan, Mar, Apr & Jun Frequency 7,5 7, 6,5 6, 5,5 5, 4,5 4, 3,5 3, 2,5 2, 1,5 1, 5 Distribution of RTD Energy Prices --- January, 215 76 1249 268 1 1 4 6 67 195 11 18 3 6 4 1 1 1 1 1 1 2 14 21-15 -125-1 -75-5 -25 25 5 75 1 125 15 175 2 225 25 275 3 325 35 375 4 425 45 475 5 >5 Occurrences Frequency 5, 4,5 4, 3,5 3, 2,5 2, 1,5 1, 5 24 17 9 9 6 43-15 -125 Distribution of RTD Energy Prices --- March, 215-1 -75-5 -25 59 364 25 4628 5 353 111 23 11 1 5 5 1 5 1 2 6 4 2 3 4 75 1 125 15 175 2 225 Occurrences 25 275 3 325 35 375 4 425 45 475 5 >5 Frequency 4,5 4, 3,5 3, 2,5 2, 1,5 1, 5 54 19 25 23 9 25-15 -125-1 Distribution of RTD Energy Prices --- April, 215-75 -5-25 474 3625 25 4189 5 281 58 17 23 8 1 2 1 1 2 5 1 1 2 6 1 1 37 75 1 125 15 175 2 225 Occurrences 25 275 3 325 35 375 4 425 45 475 5 >5 Frequency Distribution of RTD Energy Prices --- June, 215 6,5 65 6, 5,5 5, 4,5 4, 3,5 3, 2,5 2, 169 1,5 1, 55 5 326 45 3 6 4 2 6 77 28 1 7 3 2 4 5 1 2 1 1 2 1 3 3 59-15 -125-1 -75-5 -25 25 5 75 1 125 15 175 2 225 25 275 3 325 35 375 4 425 45 475 5 >5 Occurrences Slide 11
Distribution of RTD Energy Prices vs. Average Net Load --- March 215 Distribution of RTD Energy Prices --- March, 215 28, 1,1 26, 1, 9 24, 8 Net Load (MW) 22, 2, 18, 16, 7 6 5 4 3 2 RTD Energy Prices ($/MWh) 14, 1 12, -1 1, 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 24 Hours -2 March med-2*stdev min max med+2*stdev Slide 12
Distribution of RTD Energy Prices vs. Average Net Load --- April 215 Distribution of RTD Energy Prices --- April, 215 28, 1,1 26, 1, 9 24, 8 Net Load (MW) 22, 2, 18, 16, 7 6 5 4 3 2 RTD Energy Prices ($/MWh) 14, 1 12, -1 1, 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 24 Hours -2 April med-2*stdev min max med+2*stdev Slide 13
Distribution of RTD Energy Prices vs. Average Net Load --- June 215 Distribution of RTD Energy Prices --- June, 215 35, 1,1 1, 9 3, 8 Net Load (MW) 25, 2, 7 6 5 4 3 2 RTD Energy Prices ($/MWh) 15, 1-1 1, 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 24 Hours -2 June med-2*stdev min max med+2*stdev Slide 14
Load, wind and solar 1-minute variability for June 28, 215 Load, Wind, solar and Net Load --- 6/28/215 36, 5, When the RTD run does not pick-up load, wind or solar variability at least 7.5 minutes before the dispatch interval, ramp deficiencies are not reflected in the 5-minute energy prices Load & Net Load (MW) 34, 32, 3, 28, 26, 24, 22, 2, 4,5 4, 3,5 3, 2,5 2, 1,5 1, Wind & Solar 18, 5 16, Load NetLoad Wind Solar Slide 15
5-minute energy prices reflect 5-minute forecast ramping condition but may not reflect all actual intra-hour variability 35 RTD 5-Minute Energy Prices --- 6/28/215 3 25 $/MWh 2 15 1 5 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 Hours Slide 16
5-Minute RTD load forecast vs. actual load --- 6/28/215 36, RTD 5-Minute Load Forecast vs. Actual Load --- 6/28/215 6 34, 4 32, RTD Load Forecast vs. Actual Load (MW) 3, 28, 26, 24, 2-2 RTD Load Forecast Errors (MW) -4 22, 2, 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23-6 Diff RTD Load forecast Actrual Load (Exc. Pumps) Slide 17
5-Minute RTD solar forecast vs. actual solar production --- 6/28/215 5, RTD 5-Minute Solar Forecast vs. Actual Solar Production --- 6/28/215 4 4,5 4, 2 Solar Forecast/Actual (MW) 3,5 3, 2,5 2, 1,5 1, 5-2 -4-6 Solar Forecast 5-Min Errors (MW) 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 Hours 5-Min Errors RTD_Forecast Actual Solar Production -8 Slide 18
5-Minute RTD wind forecast vs. actual wind production --- 6/28/215 3,5 RTD 5-Minute Wind Forecast vs. Actual Production --- 6/28/215 8 3, 6 Wind Forecast/Actual (MW) 2,5 2, 1,5 1, 4 2-2 Wind Forecast 5-Min Errors (MW) 5-4 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 diff forecast actual -6 Slide 19
Generally when the total wind, solar and wind forecast errors are in the same direction as frequency deviations, affects on control performance are not reflected in 5-minute energy prices 1,2 Total Load, Wind and Solar Forecast Errors vs. ACE and Frequency --- 6/28/215 6.8 1, 6.6 8 6.4 6 6.2 Total Errors & ACE (MW) 4 2-2 -4-6 6 59.98 59.96 59.94 59.92 Frequency (Hz) -8 59.9-1, 1 2 3 4 5 6 7 8 9 1 11 12 13 14 15 16 17 18 19 2 21 22 23 max_min_ace Total Errors Actual Frequency Sch_Freq 59.88 Slide 2
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