- Volcanic Geothermal Systems may not be located adjacent to utility grids or local microgrids or these grids may have less capacity than the amount of electricity able to be generated by the Geothermal project. A potential way to utilise the Geothermal electricity is for the production of either Green Hydrogen or Green Ammonia.
- Hydrogen and Ammonia are Energy Carriers, able to provide transportable energy – either by surface or marine transport. Multiple good modular and scalable technologies exist to produce these products. There are a number of good suppliers of these systems.
- Hydrogen would be produced using Electrolysers powered by the Geothermal electricity. The gas could be stored in pressurised cylinders or tanks.
- Ammonia would be produced using the Hydrogen produced (above) processed together with air separation produced Nitrogen in the Haber-Bosch process. Pressurised anhydrous ammonia would be stored in containers or tanks. Ammonia’s energy density by volume is nearly double that of liquid Hydrogen, making it easier to ship and distribute in volume.
- Either Energy Carrier can be used as a fuel or to produce power by remote users.
- Hydrogen can be used with Fuel Cells or as a fuel combusted in gas turbines or conventional internal combustion engines (appropriately modified)
- Ammonia can be used with either Indirect Fuel Cells (where the Hydrogen component is disassociated first) or Direct Fuel Cells (using Ammonia directly). Subject to NOx mitigation technologies, Ammonia can be used as a fuel for engines and turbines. Ammonia is also being used in duel-fuel operation mixed with diesel.
- For countries without indigenous hydrocarbon resources but with indigenous geothermal resources, the economics can be attractive in comparison to expensive, imported, emissions intensive carbon based fuels.
