California’s drought is contributing to a dangerous cycle: Reduced water flows have reduced hydroelectric power generation, leading to an increased reliance on natural gas for the state to meet its energy needs. Since climate change is worsening California’s drought, and emissions contribute to climate change, well, the situation is not good, to say the least.
Natural gas and hydroelectric power are the two largest sources of electricity generation in California. Between 1983 and 2013, hydropower accounted for an average 18 percent of its in-state electricity production. While they are sometimes scrutinized for their negative impacts on river ecosystems, hydropower dams do not burn fuel to generate power and thus do not generate as many emissions as natural gas and fossil fuels. It is also cheaper than other forms of energy.
The California drought’s impact on hydropower has thus led to a 10 percent increase in the release of carbon dioxide from California power plants and lead to electricity cost increases of approximately $2 billion, according to a new report from the Pacific Institute.
“The impacts of the California drought – which is the driest and the hottest in 120 years of instrumental records and one of the worst in history – has had widespread impacts on all water users, including farmers, industries, cities, and natural ecosystems,” said the report’s author, Pacific Institute President Peter Gleick. “And in fact, all California ratepayers are affected by the drought as they pay for electricity that is both dirtier and more expensive than in non-drought years.”
Gleick reviewed California’s energy use during the four years of drought from October 2011 through the end of September 2015 (the official California “water year” runs from October 1 to September 30, because of the wet and dry seasonal patterns). During the four-year period, hydropower only provided 10.5 percent of total electricity generation – down from the average of 18 percent. In the most recent year, the state’s reservoirs were at record low levels and hydropower was even farther below normal, providing less than 7 percent of the total electricity generated in-state.
A mix of other energy sources was used to replace the estimated 57,000 gigawatt hour reduction in hydropower generation – primarily natural gas. As a result, Gleick estimated that up to 23 million extra tons of carbon dioxide were emitted, in addition to other air pollutants. (This figure excludes accidental leaks associated with the natural gas fuel cycle and any potential externalities such as asthma or other health impacts that may result from the emissions increase.) The average hourly marginal cost data was analyzed against the monthly hydropower anomalies to estimate the statewide electricity cost increases.
Gleick is not optimistic about the situation for 2016. He concluded the report: “As of early 2016, the drought continues: reservoir levels remain abnormally low, precipitation and especially Sierra Nevada snowpack are marginally above normal, and hydrogeneration is expected to continue to be below average until reservoirs refill. Thus, we expect costs to California ratepayers and to the environment will continue to mount.”