Lessons from the Danish production of green hydrogen using proton membrane electrolysis of clean drinking water

Abstract

With the European Union’s green strategy, and its member countries making a conscious effort to move away from fossil fuels and cut greenhouse gas emissions, there has been an uptake in technologies that produce green energy. Power-to-X has been an important topic in recent times, due to the so-called emission-free process of creating hydrogen, from excess renewable energy. The following research investigates this title of being emission-free, by analysing the method of obtaining extremely clean (pure) drinking water to produce this hydrogen. A linear equation was produced, that identifies the CO2 intensity per kWh of electricity used in producing each kg of water used to produce hydrogen. It was found that CO2 emissions occurred for small, medium, and large sized capacity projects based in Denmark. Indicatively, for a 1GW project facility, it was calculated that such a plant can produce 160,161 kg of CO2 per year, so apparently, nothing comes without a cost.