California's recent mandate of 50% renewable power utilization by 2030 will require massive amounts of energy storage. In response to this mandate, the National Fuel Cell Research Center with support from the Southern California Gas Company has launched the first U.S. research and development project to create and evaluate a carbon-free "Power-to-Gas" (P2G) system.

Using electrolyzer-based methods, the P2G concept uses the highly dynamic and intermittent electricity from renewable sources such as solar and wind, to make carbon-free hydrogen gas by breaking down water into hydrogen and oxygen. The hydrogen can be directly and safely introduced into existing natural gas pipelines at low levels, or it can be converted to methane - synthetic, renewable natural gas. Smart Grid integration of P2G followed by direct injection of renewable gas into the natural gas system provides a massive energy storage buffer that can be used to manage the electric grid when very high levels of renewable power are used. The renewable gaseous fuels that are produced and delivered by P2G can be also used to dynamically dispatch gas-fired power plants with net zero carbon emissions, and can also be used to fuel zero emission transportation applications such as fuel cell electric vehicles.