The race between wind power and hydropower to be the U.S.’s top source of renewable energy has come down to technicalities.
The American Wind Energy Association announced last week that wind energy had surpassed conventional hydropower to be the top renewable source of installed electrical capacity. Wind energy grew to 82 gigawatts of capacity in 2016, passing conventional hydropower’s 80 gigawatts.
But hydropower’s top industry group said the power source got little credit for leading the nation in electricity generation, said LeRoy Coleman, spokesman for the National Hydropower Association.
Hydropower generated 721 gigawatt hours of electricity in 2016, compared to wind power’s 610 gigawatts, according to the U.S. Energy Information Administration. It’s also projected to lead the country in generation in 2017 and 2018, according to the EIA.
“We support the growth of wind. We’re not coming at wind,” Coleman said in a phone interview, but hydropower deserves more credit for generating more electricity. “Wind or solar sneezes and everybody’s running around,” he added.
Coleman also said wind power would not have the highest capacity if one includes the 22 gigawatts of installed capacity from pumped storage hydropower, a type of energy source that is not always considered renewable. This type of hydropower uses electricity from the grid to pump water uphill, allowing plant operators to release the water downward through turbines, generating electricity in the same way as a normal hydropower plant.
The purpose of pumped storage is to balance out electricity production and demand, using excess electricity to pump water upward when there’s little demand, and releasing it back down to produce more electricity when demand is high. Pumped storage is a net consumer of electricity because it takes more energy to pump the water upward than it generates going back down.
“I would not suggest putting pumped storage with conventional hydro,” said Jonathan Cogan, a spokesman for the EIA, in a phone interview. “Ultimately, the source of the energy is from the grid, taking what might very likely or most likely be nonrenewable generation and using it to pump the water.”
The debate over whether wind or hydropower is the country’s top renewable may be a sibling rivalry, considering wind and pumped storage depend on each other. Using excess energy to store water for future generation is key for balancing out electricity production when the wind isn’t blowing, Coleman said.
“We work really well together,” he said. “We’re filling the gaps and enabling more wind onto the grid.”