Running the World on Renewables via Hydrogen Transmission Pipelines with Firming Geologic Storage
The Leighty Foundation, US
Keywords: Transmission, Firming storage, Renewables, Hydrogen, Pilot Plant
Abstract:The world’s richest renewable energy resources – of large geographic extent and high intensity – are stranded: far from end-users with no gathering and transmission systems to deliver the energy. The energy output of most renewables varies greatly, at time scales of seconds to seasons: the energy capture assets thus operate at inherently low capacity factor (CF); energy delivery to end-users is not “firm”. New electric transmission systems, or fractions thereof, dedicated to renewables, will suffer the same low CF as the energy sources, and represent substantial stranded capital assets, which increases the cost of delivered renewable-source energy. At gigawatt (GW) scale, renewable-source electricity from diverse sources, worldwide, can be converted to hydrogen and oxygen, via high-pressure-output electrolyzers, with the gaseous hydrogen (GH2) fuel pipelined to load centers (cities, refineries, chemical plants) for use as vehicle fuel, combined-heat-and-power generation on the retail side of the customers’ meters, ammonia production, and petroleum refinery feedstock. The oxygen byproduct may be sold to adjacent dry biomass and / or coal gasification plants. New, large, solution-mined salt caverns in the southern Great Plains, USA, and elsewhere in the world, can economically store enough energy as compressed GH2 to “firm” renewables at annual scale, adding great market and strategic value to diverse, stranded, rich, renewable resources. Great Plains, USA, wind energy, if fully harvested, “firmed” at annual scale, and transmitted to markets, could supply the entire annual energy consumption of the USA: ~ 100 exajoules. Firming this quantity as GH2 fuel would require about 15,000 new solution-mined salt caverns, at an incremental capital cost to the GH2 generation-transmission system of ~ 5%.