Time for demand response to prove itself. Summer heat waves are bringing the country to record-high peak power usage rates, and that means utilities are cranking up backup generators, planning for rolling blackouts — and leaning hard on their demand response providers. Earlier this week, mid-Atlantic grid operator PJM said it had already exceeded its summer peak forecast by 1.5 gigawatts, and was expecting air conditioners and refrigeration power demands to press it hard through August. Michael Bloomberg is urging New Yorkers to keep their ACs in the 80s to forestall a power crisis. Nearly half of a utility’s power costs can be tied up with peak generation, which requires infrastructure for use only a few hundred hours per year. Enter demand response — turning down power use to cushion those spikes and avoid building new power plants. Utilities and DR providers such as EnerNOC, Comverge, Constellation New Energy and others are managing about 50 gigawatts of power-down capacity today, but the Federal Energy Regulatory Commission says that figure could be more than tripled by 2020 if the right incentives and technologies are in place.