Running the World on Renewables via Hydrogen Transmission Pipelines with Firming Geologic Storage
W. Leighty, F. Crotogino
The Leighty Foundation, US
Keywords: firming, hydrogen, pipeline, cavern, stranded renewables, transmission
Abstract: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. Figure 3. For example, 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%. Germany has found that GH2 geologic storage in salt caverns is superior to compressed air energy storage (CAES) in several ways important to firming and integrating wind energy on the electricity “grid”.