The green hydrogen-water-food nexus: Analysis for Spain

Abstract

This research presents a novel approach that analyzes the water requirements for hydrogen production associated with a nationally adopted Green Hydrogen strategy. Green Hydrogen production is one of the most relevant technologies for massive renewable energy integration in transport systems, industries, or heating systems. European Union has launched a strategic roadmap for green hydrogen generation and integration in the energy chain. Spain aims to be one of the most important producers and exporters and has approved a Hydrogen Roadmap for next years, but no previous research has focused on the water requirements. This research finds that Spain's Green Hydrogen Roadmap, and a similar European one, is based on electrolyzers' peak capacity, and this causes a large uncertainty in real hydrogen production and associated water requirements. Spain represents a case study that can be a reference worldwide as it suffers from increasing droughts, has considerable tourist pressure, and is one of the most important producers of greens and fruits. This study proposes a methodology to quantify actual hydrogen production and associated water requirements and proves that current large-scale planning based on peak generation will produce a large uncertainty and could directly impact water supply security. One of the most relevant findings is that hydrogen production and water requirements must be included in these strategies to avoid future water supply tensions. An analysis of alternative water supply using desalinated water analyzes its feasibility and the effects on final cost. The outcomes are an example to be applied in similar scenarios worldwide and prove the need for an integrated energy-water-food strategy to deploy green hydrogen systems.