Techno-economic analysis of green hydrogen production and electric vehicle charging using redundant energy on a solar photovoltaic mini-grid

The trajectory of the world's energy use has moved towards the use of renewable energy to increase energy access. Solar energy's pace of growth as a result of its low cost has resulted in it being used to generate electricity for areas that do not have access to grid electricity. Thus, solar photovoltaic mini-grid systems have been deployed in several areas. Over time, it has been found that these systems generate a significant amount of redundant energy, which translates to low profitability for the mini-grid operators, as only a fraction of the system's capacity is used. This study seeks to investigate the economic feasibility of using this redundant energy for green hydrogen production and electric vehicle charging. The results revealed that both the green hydrogen production and electric vehicle charging are economically viable. Net Present Value, Internal Rate of Return and Simple Payback Period obtained for green hydrogen production are $20,000, 24.6 %, 9 years, while those of the electric vehicle charging are $109,625, 28.41 %, 4 years respectively. Over the projects’ lifetime, levelised cost of hydrogen and levelised cost of energy for charging are $6.88/kg and $0.23/kWh respectively. Furthermore, a sensitivity analysis revealed that the levelised costs for both projects are most sensitive to the plant capacity factor and capital expenditure. The study also shows that the wasted energy of the PV mini-grid could be reduced from as high as 69.95 % to nearly 0 %. This research underscores the potential of other clean energy technologies to reduce the wasted energy on existing PV systems, whiles improving the economic state of mini-grid communities.