Photovoltaic Systems
Bandar Mohammad Fadhl; Basim Mohammed Makhdoum; Kamel Guedri
Abstract
Renewable energy systems have received special attention in recent decades, mainly due to the environmental problems of using fossil fuels, fluctuation in the price of these fuels, limitations in their resources, and considerable demand for energy. Solar photovoltaic (PV) modules are among the most attractive ...
Read More
Renewable energy systems have received special attention in recent decades, mainly due to the environmental problems of using fossil fuels, fluctuation in the price of these fuels, limitations in their resources, and considerable demand for energy. Solar photovoltaic (PV) modules are among the most attractive options for power production using solar energy. A variety of factors, including the material, operating conditions, and temperature, influence PV efficiency. Elevation in the cell temperature causes degradation in efficiency and consequently the production of electricity at a constant solar radiation intensity and operating conditions. In this regard, employment of thermal management systems is considered to avoid temperature increments. Hybrid nanofluids, due to their significant thermophysical properties, are attractive options for thermal management of PV cells. This article reviews and presents studies on the thermal management of PV cells. We conclude that different factors such as the type of nanomaterial, cooling configuration, and operating conditions influence the effectiveness of hybrid nanofluids in thermal management of PV cells. Furthermore, reports suggest that the use of hybrid nanofluids, depending on the nanomaterials, may be more effective than single nanofluids in reducing the temperature of PV modules. Applying hybrid nanofluids instead of pure fluids would result in higher energy and exergy efficiencies. Aside from technical benefits, utilization of hybrid nanofluids in PV cooling could be beneficial in terms of economy. For instance, using hybrid nanofluids for module cooling can reduce the payback period of the systems.
Fuel Cells
Amarnath Gundalabhagavan; Veeresh Babu Alur; Ganesh Babu Katam; Kshitij Bhosale
Abstract
Fuel cells have been identified as a promising technology to meet future electric power requirements. Out of various fuel cells, Proton Exchange Membrane Fuel Cells (PEMFC) has been staged up as they can operate at low temperatures and also have high power density. In this article, the flow field design ...
Read More
Fuel cells have been identified as a promising technology to meet future electric power requirements. Out of various fuel cells, Proton Exchange Membrane Fuel Cells (PEMFC) has been staged up as they can operate at low temperatures and also have high power density. In this article, the flow field design of a Single Serpentine Flow Field (SSFF) has been modified to L-Serpentine Flow Field (LSFF) in order to reduce thermal and water management problems in PEMFC. A numerical study was conducted on 441 mm2 active area at 700C and 3 atm operating conditions, to evaluate various flow characteristics by comparing LSFF with SSFF, and it was observed that temperature and species flux distribution in LSFF enhanced significantly. The modification of the flow field yielded remarkable improvements in various aspects. These enhancements included a more uniform distribution of membrane water content, an impressive 8% increase in O2 consumption, a remarkable 22% improvement in product evacuation demonstrated by the H2O species profile, attributed to a 40% reduction in product travel distance. Additionally, a noteworthy 10% increase in power density was achieved. Despite a slight increase in pressure drop due to the additional bends and turns in the modified flow field, the impact on power density remained insignificant. These findings highlight the immense potential of the modified flow field to significantly enhance performance.