• Energy Research

A hybrid (photovoltaic, PV/wind/fuel cell, FC) system comprising different combinations of PV arrays, wind turbine, hydrogen tank, electrolyser, and FC has been investigated for stand-alone applications. Load demand was the electrical requirements of atypical residential apartment having a total area of 500 m2 with a peak electrical load of 35 kW and a yearly load of 24.4 MWh in Kerman, Iran. The assessment criterion for the analysis was levellised cost of energy of each system configuration. National Renewable Energy Laboratory's Hybrid Optimization Model for Electric Renewable software was utilised as the assessment tool of the present study. The effect of electrical load profile on the optimisation results has also been investigated considering a demand load profile with a low peak of 12 kW. Also, a comparison was made between the hybrid (PV/wind/diesel/bat) systems and the hybrid (PV/wind/FC) system of the current study at different fuel price scenarios.

With the decrease in the fuel price subsidy in Iran, the urge for renewable energy sources to produce cooling and freshwater in a sustainable manner is becoming a challenge. Therefore, it is necessary to specify the marginal fuel price at which a solar-based cooling/water system is compatible with a fuel-based system. To this end, a solar-powered absorption refrigeration integrated with a humidification–dehumidification desalination system was thermo-economically evaluated to produce the freshwater and cooling production rates of nearly 0.58 m3/h and 28 ton/h, respectively, as well as the solar field output temperature of 175 °C. The levelized cost of product definition, which is based on the capital costs of the system, operation and maintenance costs as well as the discount rate, was used to calculate the cooling and freshwater unit of costs (COC and COW). The results demonstrated that the locations with high solar radiation levels require smaller solar field areas and larger thermal energy storage (TES) capacities, which leads to a higher percentage of annual solar share ( $$S_{{{\text{sh}}}}$$ ), and consequently lower COC and COW values. For instance, Abu Dhabi and Athens with solar radiation levels of 1977 kWh/ $${\text{m}}^{2}$$ and 1514 kWh/ $${\text{m}}^{2}$$ , respectively, have the COC (or COW) of 0.135 $/ton (or 2.88 $/m3) and 0.387 $/ton (or 7.38 $/m3), respectively. The total annual fuel saving of the proposed system with 10 h of TES for the locations with the highest and lowest $$S_{{{\text{sh}}}}$$ s [Abu Dhabi (77.97%), Athens (29.47%)] was obtained as $${1}.{38} \times 10^{6} \;{\text{m}}^{3}$$ and 0.52 $$\times 10^{6} \;{\text{m}}^{3}$$ , respectively. In addition, since the fuel price is highly subsidized in three locations of the study, the solar-based system cannot economically compete with the fuel-based system unless the fuel cost increases by 500%, 36%, and 19% for Iran, Yemen, and United Arab Emirates, respectively.

Abstract Diesel power technology has been utilized worldwide, especially in remote regions, because of its low initial capital cost. But it has negative effects on the surrounding environment and causes global warming. On the other hand, depleting oil and fuel resources has made it inevitable to seek alternative/renewable energy resources. In Iran, the cost of fuel is highly subsidized. If Iran removes the fuel subsidy, the cost of diesel fuel would increase and the photovoltaic (PV) or hybrid PV/diesel systems would become more attractive. Hybrid photovoltaic/diesel/battery (PV/diesel/bat) systems which use PV energy, combined with diesel generation power and battery bank storage are an excellent solution to decrease diesel generator costs, pollution, and electrification of remote rural areas. In this article, a study using PV/diesel/bat power systems to meet typical load requirements in a remote region in Kerman, Iran is investigated under four different diesel generator fuel price scenarios. A simple o...