U.S. Heat Waves Split Grid Performance as PJM Tops $2,000/MWh and ERCOT Holds Near $29
Updated
Updated · marketscale.com · Aug 23
U.S. Heat Waves Split Grid Performance as PJM Tops $2,000/MWh and ERCOT Holds Near $29
3 articles · Updated · marketscale.com · Aug 23
Summary
PJM and ERCOT handled similar July air-conditioning peaks very differently: PJM prices jumped above $2,000 per megawatt-hour around its July 2 peak, while ERCOT set a July 22 demand record without emergency actions and with real-time prices near $29/MWh.
The gap points to solar-plus-battery penetration as a key divider as data center demand rises, with ERCOT's large buildout helping cover a 6 p.m. peak while PJM and SPP remained more capacity-constrained.
PJM said conservation programs prevented demand from breaking a 20-year-old record, underscoring that new 50-200 MW data center loads may increasingly need demand-response, curtailment and on-site shedding built into power plans.
SPP's demand reached nearly 58 GW on July 27 and triggered emergency measures, while Dominion Energy said nine of its top 10 power-consumption days have occurred this year in data-center-heavy Virginia.
For large-load developers, heat peaks are becoming a siting and contracting test focused less on annual clean-energy totals than on late-day capacity, storage availability and exposure to scarcity pricing.