Techno-Economic Assessment of Green Hydrogen Integration into Residential Buildings : Case Study of Beirut, Lebanon

The building sector is shifting rapidly toward cleaner energy systems to meet global decarbonization targets. This paper compares three hybrid energy systems for a residential application in Beirut, Lebanon, using a techno-economic and environmental assessment. Scenario 1 integrates photovoltaic (PV) panels, lithium-ion battery storage, and grid backup. Scenario 2 replaces the battery with a green hydrogen subsystem. Scenario 3 combines both storage technologies to explore hybrid system benefits. Simulated using HOMER Pro over a 25-year period, results show that the PV–battery–grid is currently the most cost-effective with the lowest Levelized Cost of Electricity (LCOE) and shortest payback period. The hydrogen-based system, while environmentally beneficial, has the highest cost and lowest return on investment under current market conditions. The combined system offers the highest renewable fraction (95.2%) and nearly 50% carbon dioxide (CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>) emissions reduction, striking a balance between sustainability and long-term feasibility. These findings highlight the need for cost reductions and supportive policy frameworks to accelerate hydrogen integration into the residential sector for future deep decarbonization.