Search

The research work explores the impact of temperature on Silicon photovoltaic (PV) panels, considering Nigeria as a case study. It is found that high solar radiation in Nigeria increases the surface temperature of PV panels above 25 °C of the optimal operating temperature. The redundant energy gain from solar irradiance creates heat at the rear of solar panels and reduces their efficiency. Cooling mechanisms are therefore needed to increase efficiency. In this study, we demonstrated a unique hybrid system design employing a heat exchanger at the back of the panel, with water circulated through the back of the PV panel to cool the system. The system was simulated using TRNSYS at three locations in Nigeria—Maiduguri, Makurdi, and Port Harcourt. The results of the peak annual electrical power output in Maiduguri give a power yield of 1907 kWh/kWp, which is the highest, due to a high solar radiation average of 727 W/m2 across the year. For Makurdi, the peak annual electrical power output is 1542 kWh/kWp, while for Port Harcourt the peak power output is 1355 kWh/kWp. It was observed that the surface temperature of Polycrystalline Si-PV was decreased from 49.25 °C to 38.38 °C. The electrical power was increased from 1526.83 W to 1566.82 W in a day, and efficiency increased from 13.99% to 15.01%. [ABSTRACT FROM AUTHOR]

The hybrid renewable energy system based on concentrated solar power (CSP) technology has been demonstrated as a promising approach to utilise renewable energy. To combine the configuration and operation with practical application scenarios, this study investigates three different operation modes of the hybrid system which consists of one or more components of a CSP power plant, a thermal energy storage system, photovoltaic (PV) panels, wind turbines, batteries and electric heaters. A multi-objective optimisation for the capacity parameters of subsystems is conducted for three operation modes and two typical locations, considering the actual power demand and electricity prices. Results show that cooperating with the given CSP plant, the simultaneous development of PV panels, wind turbines and batteries is recommended in Delingha, while in Lhasa, the improvement relies more on the expansion of PV panels and batteries. By providing 31.50%–38.72% of the total power, the CSP subsystem contributes significantly to providing reliable electricity in fluctuating weather conditions and at night. And 20.58–59.85 GWh of excess electricity is reused through electric heaters instead of being wasted. Furthermore, the operation in local consumption mode shows the best resilient to uncertainty of the meteorological conditions, with the deviation within 1% under forecast error of 5%–20%. • Optimal configurations are obtained for three operation modes in two locations. • Performance curves in local consumption mode show consistency across sites. • Similar trends but higher profit is obtained in VPP mode compared to sales mode. • Electric heaters enable 20.58–59.85 GWh of electricity reused instead of wasted. • A deviation of 1 % is seen in local consumption mode for forecast errors of 5%–20 %. [ABSTRACT FROM AUTHOR]

The new challenge of the European Commission is to limit water consumption in Concentrating Solar Power (CSP) plants, especially significant in the cooling process. Hybrid cooling systems are presented as a potential solution to achieve water consumption reduction since they also avoid a high penalty of efficiency loss in the power block. In this work, a hybrid cooling pilot plant installed at Plataforma Solar de Almería is evaluated experimentally. The system has been tested under different ambient and operating conditions to analyze their influence on the water and electricity consumption. The results reveal that significant water savings were achieved in comparison with the conventional only-wet configuration. Concretely, a maximum water consumption saving of 67% was found at high ambient temperatures (between 25 and 30 °C) and for a thermal load of 80% when a hybrid configuration was used. The optimal operating strategies that achieve a tradeoff between low water and electricity consumption have been identified by two efficiency indexes: the specific electricity and water consumption. The parallel configuration was the optimal one in most of the cases. At high ambient temperatures and 80% thermal load, the electricity and water consumptions of this configuration were 0.033 kW e /kW th and 0.071 L/kW th , respectively. • Test campaign to investigate the optimal configurations of a hybrid cooler. • Trade-off between water and electric energy consumption under several conditions. • Specific electricity consumption and specific water consumption for the evaluation. • Maximum water consumption saving of 67% for parallel configuration split ratio 25%. • Maximum electricity reduction of 59% for parallel configuration split ratio 50%. [ABSTRACT FROM AUTHOR]