Drought Dries Up California’s Hydropower but Not its Vision for a Renewable Energy Future



Credit: NREL and MWH Global

California legislators recently passed a bill to increase the state’s Renewable Portfolio Standard (RPS) to require 50% renewables by 2030. That is, by the year 2030, at least half of all electricity consumed in the state must come from qualified sources like geothermal, solar, wind, and small hydroelectric. Raising an RPS can be a great way to encourage investment in renewable energy, and pursuing additional low-emissions sources may be particularly critical today as California suffers production losses from its hydroelectric facilities.

In 2014, California generated approximately 47% less conventional hydropower than its ten-year average, according to data from the U.S. Energy Information Administration. While hydropower is often recognized as a low-emissions resource, most states limit the extent to which it qualifies under an RPS. This makes sense for encouraging investments in new technology, since many hydroelectric facilities were already online and operational before RPSs were adopted. (It also makes sense given hydropower’s significant environmental shortcomings.)

Unfortunately, excluding hydropower from an RPS can also mean that when hydropower generation decreases, producers have little incentive to generate the replacement power from a renewable energy source. Indeed, California lost hydropower and primarily saw a corresponding rise in natural gas production, according to a report from the Pacific Institute. The report estimates that from 2012 to 2014 alone, the switch cost ratepayers $1.4 billion and raised California’s carbon dioxide-equivalent emissions by 8%. Those emissions included almost 14 million tons of carbon dioxide, plus other pollutants like nitrous oxides, volatile organic chemicals, and particulate matter. To be fair, California also saw more renewable facilities come online, but some say the new facilities were simply already in the pipeline.

Hopefully California’s new RPS will bring more renewable energy facilities online and help reduce the risks of an increasingly uncertain energy future. Droughts might reduce hydroelectric power (of late, something not unique to California), but that does not have to mean increased greenhouse gas emissions. Perhaps more Western states should consider following Hawaii’s and California’s leads in raising their RPS goals before they, too, face declining hydropower.