POSSIBILITIES FOR THE USE OF HELIOTHERMIC PLANTS FOR GENERATION OF GREEN HYDROGEN VIA DESALINIZED WATER

Abstract

Fresh water has become a precious input due to its scarcity mainly due to climatic effects that affect the water cycle. With the forecast of an increase in population and an increase in the demand for fresh water for consumption, agriculture, and industry, it is necessary to investigate opportunities for the generation of this input. Brazil, although considered a source of fresh water, has been going through a water crisis, with water shortages to supply agriculture and hydroelectricity generation. A current global trend is the production of green hydrogen for export via freshwater electrolysis, which is preferably extracted from regions that have an abundance of renewable energy, to contribute to the mitigation of emissions and global warming. This article presents the results of preliminary analyzes of the technical and economic feasibility of eight systems to produce green hydrogen for export, from desalinated sea water, aiming to preserve fresh water for other nobler purposes. All the systems analyzed use electric and (or) thermal energy generation plants from solar and wind energy, with emphasis being given to the heliothermic energy concentration systems, consisting of a parabolic trough-type plant coupled to a thermal energy storage system. It is observed that heliothermic systems, generators of electrical and thermal energy, require higher investment costs, however, they have hydrogen production costs compatible with those of other systems. Additionally, heliothermic systems provide uniform, dispatchable daily hydrogen production. It is also verified that desalination plants have a negligible investment cost compared to the investment cost of power and hydrogen generation plants. It is concluded that green hydrogen generation systems via desalinated water, coupled with renewable energy plants can be viable mainly in regions close to the coast of the country