PEC versus PV-E A Future Potential Comparison

Abstract

The standard hydrogen production method uses methane as source. In this process the greenhouse gas CO2 is emitted. An alternative hydrogen production method is from water with an electrochemical reaction. A technology which uses solar energy to produce hydrogen from water is a photoelectrochemical (PEC) cell. The PEC cell converts the photons into separated electrons and holes, which drives the electrochemical water splitting reaction. Unique about the PEC cell is both photon conversion and the electrochemical reaction are in one device. That should lead to cheaper hydrogen production and higher solar to hydrogen efficiencies, compared to it’s direct competitor a PV-E system (a PV panel connected to an electrolyser). However, a PEC cell is still far from commercialisation, while the equipment of a PV-E system is available on the market. Therefore, the aim of this research is to compare the future potential of PEC vs PV-E. In this research are first comparable PEC and PV-E systems designed for the short term. In the second part is the future potential of both systems compared with more optimistic values. The results show that a lower future PEC system cost compared to PV-E could be possible, but that this difference is small. A lot of development and upscaling is expected needed to achieve this future lower cost for PEC, without being cost competitive in the market. Therefore, is it considered unlikely for a PEC cell to achieve a lower hydrogen cost per kg than a PV-E system.