Preliminary findings of research on power-to-gas storage conducted at the and funded by SoCalGas show that the technology conceivably could be used to stockpile substantial amounts of renewable energy, the academics reported on March 30. In fact, they believe it out-performs lithium-ion battery storage.
At UC Irvine’s International Colloquium on Environmentally Preferred Advanced Generation (ICEPAG 2017) last week, researchers demonstrated that the campus solar microgrid could increase the portion of renewable energy it uses by tenfold – from 3.5 percent to 35 percent – by implementing a power-to-gas strategy.
The new finding comes from a pilot project begun with funding from SoCalGas and the participation of Proton OnSite, a Wallingford, Connecticut-based company that claims to be “the world’s largest manufacturer of on-site hydrogen generators.”
For the project, Proton OnSite supplied an electrolyzer that creates hydrogen from electricity and water. UC Irvine engineers and graduate students then launched a study to determine how advantageous the technology might be – and how feasible it would be to use it for statewide or regional power grids.
The study used data from the UC Irvine campus solar microgrid, which produces about 4 MW of peak power. Simulations by the researchers demonstrated that, by storing excess solar power on sunny days and using an electrolyzer to produce renewable hydrogen, the microgrid could support an additional 30 MW of solar panels.
Indeed, according to SoCalGas, a 5 percent blend of hydrogen in the utility’s natural gas system would provide storage capacity equivalent to worth of battery systems (if purchased at the U.S. Department of Energy future cost of per kWh).
Renewable hydrogen can also be used in hydrogen fuel cell vehicles or converted to methane for use in a natural gas pipeline and storage system.
The research team noted that power-to-gas presents a significant advantage over lithium ion batteries, which store energy for shorter time periods and require extensive construction of battery systems and infrastructure.
“This research clearly shows that power-to-gas technology can increase the use of renewable energy and should be an important component in meeting clean energy and greenhouse gas reduction goals,” said , director of Business Strategy and Advanced Technology at SoCalGas.
“The ability to increase the mix of renewables on campus by tenfold is truly significant,” said , associate director of the Advanced Power & Energy Program (APEP) at UC Irvine. “With power-to-gas technology, you don’t need to stop renewable power generation when demand is low. Instead, the excess electricity can be used to make hydrogen that can be integrated into existing natural gas pipeline infrastructure and stored for later use.
“The Southern California Gas Company system alone is made up of over 100,000 miles of pipeline,” Brouwer added. “This study suggests that we could leverage that installed infrastructure for storage and significantly increase the amount of renewable power generation deployed in .”
Power-to-gas systems already are in place in Canada and Germany.