Techno-enviro-economic analysis of hydrogen production via low and high temperature electrolyzers powered by PV/Wind turbines/Waste heat

The current study presents techno, economic and environmental assessment of hydrogen production systems using low (PEM, Proton exchange membrane) and high temperature electrolyzers (SOEC, solid oxide electrolyzer cell) powered by different energy sources. These sources are PV panels, wind turbines, Rankine cycle based on waste heat recovery, and electricity from grid. The mathematical model of the whole system is constructed and solved using MATLAB/Simulink based on actual data: climatic conditions and waste heat streams. The system efficiency and hydrogen production rate are evaluated for all systems. A sensitivity analysis is performed to investigate the Levelized cost of hydrogen (LCOH) and Levelized cost of compressed hydrogen (LCOCH) under three factors: interest rate, inflation rate, and degradation rate. Additionally, economic risk evaluation based on payback period, internal rate of return, and net present value are conducted to investigate the investment op-portunity. The results indicate that the highest overall efficiency is obtained using waste heat systems at 22.91%, and the low efficiency is 11.6% for PV systems. The LCOH varies from 1.19 to 12.16 $/kg, while the LCOCH varies from 5.03 to 17.1 $/kg. The lowest value is obtained when waste heat is employed, followed by the grid, PV panels, and wind turbines. Wind turbine systems are not recommended at selling prices of 8 and 10 $/kg, but the waste heat system shows good potential for an investment opportunity. Finally, according to the system configurations, annual CO2 emissions reduction ranges from 4.81 to 1365 tons and carbon credit gain (CCG) from 192 to 54,600 $.