Techno-economic assessment of a solar-powered green hydrogen storage concept based on reversible solid oxide cells for residential micro-grid: A case study in Calgary

Solar photovoltaic (PV)-based electricity production has gained significant attention for residential applications in recent years. However, the sustainability and economic feasibility of PV systems are highly dependent on their grid-connected opportunities, which may diminish with the increasing penetration of renewable energy sources into the grid. Therefore, securing reliable energy storage is crucial for both grid-connected and off-grid PV-based residential facilities. Given the high capital costs and environmental issues associated with batteries, hydrogen energy emerges as a superior option for medium to large residential applications. This paper proposes an innovative concept for PV-based green hydrogen production, storage, and utilization using solid oxide cells within residential micro-grids. It includes comprehensive techno-economic and environmental analyses of the proposed system, utilizing dynamic solar data, with a case study focusing on Calgary. The results indicate that seasonal hydrogen storage significantly enhances the feasibility of meeting the electricity demand of an off-grid residential community consisting of 525 households connected to a 4.6 MW solar farm. With the inclusion of Canadian clean hydrogen tax incentives, the monthly cost per household is approximately $319, potentially decreasing to $239 with advancements in solid oxide cell technology and extended lifetimes of up to 80,000 h. Furthermore, implementing this system in Calgary could result in a monthly reduction of at least 250 kg of CO2 emissions per household.