Throughout final week’s heat-wave-driven grid emergency in California, grid operator CAISO and the state’s utilities despatched out determined calls to demand response suppliers, behind-the-meter battery aggregators, electric-vehicle charging suppliers, microgrid operators and backup generator homeowners, searching for no matter assist they may present.
The decision was answered. In line with CAISO and the California Public Utilities Fee, client conservation and demand-side sources had been essential in avoiding extra rolling blackouts like these CAISO ordered the evenings of Friday, Aug. 14 and Saturday, Aug. 15.
“Conservation efforts are the one method we’ve got gotten by these peaks,” CAISO President Steve Berberich mentioned final week.
Whereas the grid operator lacks visibility into how a lot load discount got here from these voluntary energy-saving choices, it may well measure the roughly 1,300 megawatts of residential and commercial-industrial demand response it secured in the course of the disaster.
It additionally tallied a whole lot of megawatts from out-of-market responses, in keeping with a letter from CAISO and the CPUC laying out plans for a “postmortem” evaluation of the emergency for Gov. Gavin Newsom and state leaders. Silicon Valley knowledge facilities offered about 100 megawatts by switching to backup energy techniques. Army microgrids, ships and backup turbines delivered about 23.5 megawatts, and microgrids funded by state analysis grants offered one other 1.2 megawatts per day.
Microgrids, solar-plus-storage techniques, EV chargers, dispatchable power masses and different distributed power sources are going to play an more and more vital function in shaping California’s electrical energy supply-demand steadiness because it seeks to succeed in its purpose of 100 % carbon-free power by 2045.
Past these backup techniques, behind-the-meter batteries from suppliers together with Stem, Sunrun, Enel X and Tesla shifted their typical working schedules to maximise effectiveness by 9 p.m. to match the state’s “web peak,” or complete grid demand minus wind and photo voltaic. Electrical-vehicle charging operators like Tesla and Enel X additionally inspired prospects to keep away from charging throughout peak hours.
Surya Panditi, CEO of Enel X, famous that the corporate’s demand response, behind-the-meter battery and EV charger property had been in a position to ship about 150 megawatts per day in the course of the disaster. “If…the correct of financial assemble [is in place], everybody advantages.”
Obstacles to behind-the-meter participation
However this month’s disaster has additionally revealed a spot between the grid-balancing potential of demand-side sources and the insurance policies wanted to convey them to bear, trade individuals say.
“We delivered about 50 megawatts of aid to the grid on Friday night — however we might have deployed about 50 megawatts extra if all of the insurance policies had been in place,” mentioned Ted Ko, Stem’s vice chairman of coverage and regulatory affairs. “What’s ironic is that the [CPUC] and CAISO have been placing up all these limitations to us taking part, after which they referred to as us and mentioned, ‘Hey, are you able to do that for us without cost?’”
A 2019 paper from the California Photo voltaic & Storage Affiliation lays out a lengthy listing of such limitations. One key subject is the foundations meant to forestall “double-counting,” which refers to resource-gaming or distorting the market by getting paid twice from completely different packages for a similar service.
This prohibition has been utilized in illogical methods, Ko contends. For instance, till lately, batteries receiving funds from the state’s Self-Technology Incentive Program had been barred from most demand-side sources packages — although SGIP’s upfront set up incentives are distinct from grid-services funds.
The CPUC has made modifications to permit SGIP techniques to take part in sure distribution grid packages. But it surely hasn’t but set requirements for a way “multiuse purposes,” reminiscent of behind-the-meter sources incomes incentives from different state packages, can take part in California’s key program for securing capability to satisfy grid demand peaks, the Useful resource Adequacy (RA) program.
CAISO has criticized the CPUC for failing to safe sufficient RA to forestall final week’s grid emergencies, and reforming this system is excessive on each businesses’ agendas. Whereas some SGIP-backed solar-storage aggregations in California qualify as RA, different utility initiatives searching for behind-the-meter capability have barred individuals from receiving SGIP or different set up incentives, the 2019 report states.
Gradual progress on reforms to demand response
Thomas Folker, CEO of Leap, an organization that helps renewables aggregators entry markets, agreed that modifications are wanted to unlock extra demand-side capability in California. Final week, Leap offered between 50 and 60 megawatts of load discount day by day from the combo of Nest good thermostats, EV chargers, water pumps and commercial-industrial load controls it bids into CAISO’s power markets for aggregators.
A lot of these sources are organized beneath the Demand Response Public sale Mechanism (DRAM) pilot program, which permits aggregators to earn cash in two methods: by getting into into RA contracts with utilities and by bidding into CAISO’s day-ahead and real-time power markets.
DRAM hasn’t seen its funds expanded to permit broader participation by renewables aggregators over the previous few years because the CPUC debates its subsequent steps, limiting its development. In the meantime, conventional utility-run demand response initiatives reminiscent of the Capability Bidding Program pay lower than what’s accessible from DRAM, with funds disconnected from real-time power market costs, he mentioned.
CAISO permits distributed power sources (DERs) to take part straight in its markets, however the Distributed Vitality Useful resource Supplier program hasn’t enlisted any aggregators but. DER suppliers say that’s as a result of CAISO units deal-breaking necessities, together with the have to be accessible always, which prevents different revenue-generating alternatives.
Even DRAM has its limitations, Folker mentioned. For instance, RA guidelines require sources to decide to not less than 4 hours of steady supply. That’s meant to guarantee that CAISO can entry a dependable, constant peak discount over time. But it surely additionally limits how “surgically” Leap can bid load-reduction potential into CAISO’s market throughout its web peak, when the solar units, and the buffer between provide and demand dwindles essentially the most.
Narrowing that minimal bid requirement to 2 hours, for instance, might double batteries’ load-reduction potential, by halving the period of time they’re required to attract upon their restricted storage capability. Capability from householders turning off air conditioners or EV drivers delaying charging is also boosted by shortening how lengthy they’re requested to do it, he mentioned. Since CAISO’s rolling blackouts had been pressured throughout a two-hour window, this type of centered improve in capability might have made a big distinction.
Letting behind-the-meter property cost up the grid
Behind-the-meter sources can also’t ship power again to the grid since demand response packages are constructed for load discount, not power export. Altering these guidelines might enable them to play a way more aggressive function, Ko mentioned.
Stem sought emergency authorization from utilities to export from its batteries final week, however the firm “couldn’t make that occur quick sufficient,” he mentioned. “We don’t have the constructs in place to dispatch and receives a commission for DERs to assist out in these emergency conditions.”
Permitting behind-the-meter power export would require reforms to CAISO’s Proxy Demand Useful resource and Reliability Demand Response Useful resource packages that set up a lot of the state’s utility demand response exercise, he defined. CAISO, the CPUC and the California Vitality Fee are planning a joint workshop to debate the potential to supply RA credit score to “hybrid” solar-storage behind-the-meter sources, a continuing over which the energy-export subject is prone to loom massive, he mentioned.
There’s a whole lot of potential worth being left on the desk, Ko mentioned. In line with analysis from Stem, photo voltaic installer Sunrun and software program startup Station A, the state’s latent solar-storage capability might present about 9 gigawatts of grid capability beneath ultimate circumstances.
California’s practically 20-year-old RA assemble faces main modifications to adapt to a future of accelerating ranges of intermittent clear power. Key questions embrace how a lot to depend on out-of-state imports and how you can enlist power storage to exchange a declining natural-gas energy plant fleet.
However how you can faucet California’s fast-growing behind-the-meter capability will even be an vital a part of the answer, mentioned Ben Kellison, WoodMac’s director of grid analysis. One huge query will likely be to find out “how a lot of the emergency capability was referred to as by market mechanisms versus how a lot simply confirmed up out of a way of societal obligation or goodwill” — and to find out whether or not insurance policies want to vary in an effort to pull a few of the latter class into the previous.