Texas is heading into summer with a growing supply of privately-generated electricity, reflecting the surge of small-scale power generators that businesses have been installed to provide their own back-up power and make money when prices spike during extreme weather.
A report by the Austin advocacy group Texas Clean Energy Coalition and the Boston consulting company Brattle Group found that back-up power supplies, including fast-starting diesel-powered and natural gas-powered micro-turbines along with solar panels, can generate about 1,300 megawatts of power in Texas, the equivalent of building nearly three utility-scale combined-cycle electric generating plants.
Combined cycle power plants built before 2014 have a generation capacity of about 500 megawatts, according to the Department of Energy.
Small-scale power generation increased 62 percent between 2015 and 2017, according to the study.
The state's grid manager the Electric Reliability Council of Texas confirmed that Texas has 1,300 megawatts of registered and unregistered distributed energy sources. Generators smaller than 1 megawatt -- enough to power about 200 homes during a hot summer day in Texas -- are not required to register with ERCOT.
Texas has 78,000 megawatts of expected capacity for peak demand, with back-up power supplies representing about 1.7 percent of the total.
Texas regulators have been trying to get a handle on the width and breadth of privately-installed micro-turbines and community and residential sized solar panels to gauge whether they can step in to supply electricity if Texas has a heat wave or if scheduled plants go offline.