Environmental performance of a hybrid solar-hydrogen energy system for buildings

Abstract

As the residential sector has a significant environmental impact, there is growing pressure to move away from heavy reliance on fossil fuels and towards renewable technologies. One approach to avoid burning fossil fuels in this sector is a hybrid solar-hydrogen energy system based on photovoltaic panels for electricity supply, a battery for short-term storage, and a hydrogen system consisting of a fuel cell, electrolyzer, and hydrogen tank for long-term storage. This study uses the life cycle assessment method to analyze the environmental impact of such a system and compares the results to a reference system with no hydrogen components in both off-grid and grid-connected scenarios. The results show that the solar-hydrogen system causes lower greenhouse gas emissions in the off-grid scenario. Overall, it is significantly beneficial in 6 out of 16 impact categories. In contrast, the off-grid reference system, equipped with a diesel generator as a backup power source, has lower burdens in 7 impact categories and the single score result. The production of the hydrogen tank is identified as the primary driver of emissions of the solar-hydrogen system. In the on-grid scenario, the grid-connected reference system is beneficial in all impact categories.