Green Hydrogen Production Using Solar-Powered Electrolysis: Nanocatalyst Engineering, System Optimization, and Techno-Economic Assessment for Pakistan

Abstract

Pakistan's severe energy security challenges, heavy reliance on imported fossil fuels, and exceptional solar resource base create both urgent necessity and unique opportunity for green hydrogen production via solar-powered electrolysis. This comprehensive review synthesizes recent advances in nanocatalyst engineering, water electrolysis technologies, geospatial planning, and techno-economic assessment specifically tailored for Pakistan's energy transition. The electrochemical water splitting process comprising hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) faces fundamental kinetic barriers that drive research toward earth-abundant transition metal nanocatalysts. Interfacial engineering strategies coupling NiFe-layered double hydroxides with MoS₂ scaffolds, defect engineering introducing oxygen vacancies, and single-atom catalyst architectures (e.g., Ru₁/D-NiFe LDH) demonstrate bifunctional HER/OER activities with overpotentials as low as 18 mV at 10 mA/cm², representing a 14% reduction in specific electrical energy consumption. Technology evaluation reveals critical trade-offs: Alkaline Water Electrolysis offers low capital costs ($500–800/kW) and extended lifetimes (>80,000 hours) but limited dynamic response, whereas Proton Exchange Membrane Electrolysis provides rapid ramping (10–100%/second) at higher costs ($1,000–1,500/kW). Geospatial modeling identifies 71,170 km² of suitable land across southern Sindh and Balochistan, yielding a technical green hydrogen potential of 68.96 Mt/year significantly exceeding domestic demand. Techno-economic analysis for a 100 MWp solar PV with 50 MW electrolyzer configuration establishes a baseline Levelized Cost of Hydrogen ranging from $3.40–$4.27/kg, with PV oversizing and hybrid electrolyzer architectures identified as critical optimization levers. Achieving cost targets below $2.00/kg by 2030 requires coordinated advances in electrolyzer efficiency (70–74%), solar PV cost reduction ($400–500/kW), and concessional financing mechanisms (7.5–8.5% WACC), positioning Pakistan as a potential competitive hydrogen supplier in South Asian and global markets.