METHODS AND SYSTEMS FOR ENERGY CONVERSION AND GENERATION INVOLVING ELECTROLYSIS OF WATER AND HYDROGENATION OF CARBON DIOXIDE TO METHANE

摘要

The invention relates to methods and systems of converting electrical energy to chemical energy and optionally reconverting it to produce electricity as required. In preferred embodiments the source of electrical energy is at least partially from renewable source. The present invention allows for convenient energy conversion and generation without the atmospheric release of CO2. One method for producing methane comprises electrolysis of water to form hydrogen and oxygen, and using the hydrogen to hydrogenate carbon dioxide to form methane. It preferred to use the heat produced in the hydrogenation reaction to heat the water prior to electrolysis. The preferred electrical energy source for the electrolysis is a renewable energy source such as solar, wind, tidal, wave, hydro or geothermal energy. The method allows to store the energy gained at times of low demand in the form of methane which can be stored and used to generate more energy during times of high energy demand. A system comprising an electrolysis apparatus and a hydrogenation apparatus, and a pipeline for the transportation of two fluids, is also described.