Assessment of hydrogen and Lithium-ion batteries in rooftop solar PV systems

Abstract

Hydrogen batteries are currently gaining attention as a promising clean energy storage technology. However, limited knowledge is available at present on the technical and financial performance of Hydrogen batteries in rooftop solar PV (RSP) systems. This study models the operation of a commercial Hydrogen battery in RSP system, using Time of Use and Solar Feed-In tariffs, and compares the performance with a commercial Lithium-ion (Li-Ion) battery under solar and arbitrage scheme. The model considers battery aging and performance degradation, with results suggesting that both hydrogen and Li-Ion batteries can reduce grid dependency and lower electricity costs by minimizing grid imports. However, the Li-Ion battery outperforms the hydrogen battery in better capacity utilisation due to lower roundtrip energy losses. The Li-Ion battery generates higher net income, achieving a payback period 9 years earlier in the arbitrage scheme and 1 year in the solar scheme, compared to the Hydrogen battery. However, the Hydrogen battery demonstrates a longer lifespan, enduring 18 % fewer charge-discharge cycles than Li-Ion battery. This makes the Hydrogen battery suitable for remote applications requiring extended duration of energy storage. The methodology developed in this study provides a valuable framework for evaluating the potential adoption of Hydrogen and Li-Ion batteries globally.