Abstract

Hydrogen energy systems are being developed to replace fossil fuels–based systems for transportation and stationary application. One of the challenges facing the widespread adoption of hydrogen as an energy vector is the lack of an efficient, economical, and sustainable method of hydrogen production. In the short term, hydrogen produced from fossil fuels will facilitate a transition to the hydrogen economy. In the long term, renewable hydrogen production methods will have to be adopted as resources become scarce, causing the price of fossil fuels to rise. In this work, a number of methods have been considered for the renewable production of solar hydrogen, and thermochemical sulphur-iodine cycles proved to be the most promising. The sulphur-iodine cycles have the highest efficiencies and use widely available reactants with relatively straightforward reaction mechanisms, which make them the most economical and technically feasible option for renewable hydrogen production.