Feasibility of Hydrogen Energy in Multi End-use Setting in Buildings

In the present study, an investigation is conducted to assess the feasibility of producing hydrogen from water and storing it to be used later for electricity generation in a fuel cell. For this reason, it is assumed that a group of hotels that already own a reverse osmosis (RO) desalination unit and an installed 5-MW photovoltaic (PV) system, form a cooperative and share the usage of the hydrogen system. The sales of the byproduct oxygen is also of consideration in the viability study. Hydrogen is generated throughout the year under two scenarios; In the winter period where off-peak electricity is used, and in the remaining seasons where daytime photovoltaic electricity in the grid is used for water splitting by electrolysis to obtain hydrogen. In both scenarios hydrogen is stored during off-peak hours and electricity is generated in a fuel cell during peak hours in North Cyprus. Through the economic analysis, it has been noticed that the system is non-feasible under the current tariff billing. However, using optimization methods through sensitivity analysis and applying Monte Carlo simulation, together with proposing a multi-tariff billing system, it has been observed that the system can become feasible. Through optimization, the fuel cell energetic and exergetic efficiencies are increased to 50.19% and 48.09%, respectively. It is found that the break-even peak and off-peak tariff prices should be 0.55 and 0.275 $/kWh, respectively, with expected reduction in fuel cell and storage unit costs in the future, to obtain savings-to-investment ratios above unity. The analysis was done over a lifetime of 15 years and discount rate of 2%.