Techno-economic and environmental assessment of a hybrid PV-PEM electrolyser system for hospital energy and oxygen supply in India

Hospitals require reliable energy supplies while facing increasing pressure to reduce greenhouse gas emissions and grid dependence. This study presents an hourly techno-economic and environmental assessment of a hybrid photovoltaic-proton exchange membrane electrolyser (PV-PEMEL) system for electricity supply and co-production of hydrogen and oxygen across five Indian locations: Guwahati, New Delhi, Jodhpur, Bengaluru, and Srinagar. Location-specific solar resources, hospital electricity demand, and a priority-based energy management strategy were considered. Annual PV generation ranged from 507.54 to 588.56 MWh, directly supplying 50.5-52.4% of hospital electricity demand. Annual hydrogen and oxygen production ranged from 5.8-7.1 tonnes and 46-56 tonnes, respectively. The levelized cost of electricity (LCOE) ranged from 0.027-0.078 $ kWh⁻¹, the levelized cost of hydrogen (LCOH) from 4.56-5.99 $ kg⁻¹, and the payback period from 12.84-15.47 years. LCOE remained below applicable grid tariffs across all locations, while LCOH for Bengaluru and Jodhpur was at or within the upper boundary of the reported Indian green hydrogen cost range. Annual CO₂ mitigation ranged from 182.88-198.64 tonnes year⁻¹, while hydrogen production required only 1.5-1.8% of total hospital water demand. Additional analyses for Guwahati showed limited sensitivity to load-profile variations and strong economic sensitivity to co-product valuation, hydrogen price, capital cost, and financing conditions. Scaling from 50 to 200 beds reduced LCOE and LCOH by 57.69% and 29.7%, respectively, while component degradation increased the lifetime LCOE and LCOH by 24.35% and 12.19%, respectively. Overall, Bengaluru and Jodhpur exhibited the most favourable combined economic and environmental performance.