Low tech photovoltaic panels (PVPs) installed in the early ’80s are now coming to the end of their life cycle and this raises the problem of their proper disposal. As panels contain potentially toxic elements, unconventional, complex and costly procedures are required to avoid environmental health risks and in countries where environmental awareness and economic resources are limited this may be especially problematic. This work was designed to investigate potential risks from improper disposal of these panels. To accomplish this aim an exhausted panel was broken into pieces and these were placed in water for 30 days. The resulting leached solution was analyzed to determine chemical release or used in toto, to determine its potential toxicity in established tests. The end points were seed germination (on Cucumis sativus and Lens culinaris) and effects on early development in three larval models: two crustaceans, Daphnia magna and Artemia salina, and the sea urchin Paracentrotus lividus. Our results show that the panels release small amounts of electrolytes (Na, Ca and Mg) into solution, along with antimony and manganese, with a concentration under the accepted maximum contaminant level, and nickel at a potentially toxic concentration. Developmental defects are seen in the plant and animal test organisms after experimental exposure to the whole solution leached from the broken panel. The toxic effects revealed in in vitro tests are sufficient to attract attention considering that they are exerted on both plants and aquatic animals and that the number of old PVPs in disposal sites will be very high.

In Turkey, Southeastern Anatolia region is the highest in terms of solar radiation level. However, the provinces in the region are subject to Particulate Matter (PM) coming from the Sahara desert, the Syrian Desert and the Arabian Desert by atmospheric transport. The daily limit of PM₁₀ and PM₂.₅ set by WHO for health is often exceeded in Sanliurfa. PM₁₀ and PM₂.₅ pollutants also accumulate on the Photovoltaic (PV) panels and cause loss of PV panel performance. In this study, the effects of atmospheric dust deposition on the performance of PV panel was determined for both monocrystalline and polycrystalline technologies under Sanliurfa atmospheric conditions. Two panels with the same characteristics were used for each PV panel group from 2 different PV technologies. One of the panels in the group was cleaned by washing with distilled water every Monday while the other was not cleaned. Thus, the effect of the dust accumulation on the PV panel was determined by comparison to the cleaned PV panel. PV panel power is measured with I–V meter. Panel surface temperature, solar radiation and other meteorological parameters are measured simultaneously. The measurements were done every Monday, Wednesday and Friday at 12:00 am from May 1 to December 31, 2019. It is observed that the dust accumulation reduces the PV power output up to 8% depending on the amount of radiation. During the summer months, the power loss on the average is 4.33% for monocrystalline and 4.57% for polycrystalline. In the autumn months, it is less than 1.77%.

Photovoltaic (PV) power plants have shown rapid development in the renewable sector, but the research areas have mainly included land installations, and the study of fishery complementary photovoltaic (FPV) power plants has been comparatively less. Moreover, the mechanism of local microclimate changes caused by FPV panels has not been reported. This work revealed this mechanism using a physical model to illustrate the impact of FPV power plants in a lake on the environment. The results indicated that the lake becomes a heat sink after deploying the PV panel on water. The comprehensive albedo (0.082) decreased by 18.8% relative to the free water surface (0.101). The water energy change was dominated by the water–air vapor pressure deficit. In addition, the FPV panels had a heating effect on the ambient environment; however, the range of this effect was related to the water depth. The installation had an obvious heating effect on surface water.

The goal of this research is to investigate the effect of utilizing selective liquids as absorption filters to prevent PV module overheating by blocking the undesirable part of the spectrum (long wavelength) while allowing the beneficial part of the spectrum (visible light and near infrared) to pass through. The fluids were evaluated on two different panels, and their results were compared to those of a control panel. In this work, two liquids were used and tested: copper sulfate solution (CuSO₄·5H₂O) and distilled water as absorption filter; each was arranged in such a way that it flows evenly over the surface of a PV module through a cavity mounted on the top side of the PV module. In addition, a standard PV panel was employed as a comparison. The average power produced by the PV when pure was used as an optical filter is 31.3%, while it was 11.3% when copper sulfate solution was used compared with base unit. Furthermore, the cooling effect of pure water on the PV was more efficient than that of copper sulfate solution, with an average PV temperature drop of 15% compared with 7.5% when copper sulfate is used compared with the base unit panel’s performance improved by an average of 31.3% when distilled water was used as the absorption filter, compared to the reference panel’s performance, while the copper sulfate solution improved the panel’s performance by an average of 11.3% compared to the reference panel’s performance.

The unavailability of sunlight during nighttime and cloudy weather condition has limited the usage of solar cookers throughout the day. This study will attempt to engineer a solar cooker with PV (photovoltaic panel), evacuated tubes with CPC reflectors, battery, and charge controller using the microcontroller PIC 16F877A. A mathematical model is developed to predict the electrical power (Eₚ) required during cloudy weather condition and nighttime as well as the temperatures occurring at different parts of the cooker. The proposed model is validated against experimental observations gathered for one of the typical working days of the system. The cooker is tested for various cooking loads to find the cooking time, and it is proven that the proposed cooker can be utilized over 24/7 without interruption.

A massive bird dropping (BD) deposition on the common rectangular flat plate (RFP) of photovoltaic (PV) module is a matter of great concern in Western Rajasthan (WR) that diminish the overall energy production capacity of the system remarkably. In this research article, a prototype novel flat plate (NFP) design of a front glass cover of PV module is proposed to prevent the impact of BD settlement by the restriction of bird’s sitting/movement on the front glass cover. In this regard, the performance analysis of PV module with common RFP and newly designed NFP glass covers has been assessed at the different inclination β° (0–90). The BD accumulation onto the both glass covers was explored by the optical transmittance profiles at the different tilt angles, i.e., explained by bird movement on each flat glass surfaces. Consequently, a significant amount of output electric energy has been gained in NFP design rather than RFP corresponding to particular tilt regions TR I (0° ≤ β ≤ 25°), TR II (25° ≤ β ≤ 60°), and TR III (60° ≤ β ≤ 90°). According to the results achieved, an excellent level of improvement in average power loss, ~ 97.85%, corresponding to optimal TR (III) has been detected by employing NFP glass collector.

Solar energy will assist in lowering the price of fossil fuels. The current research is based on a study of a solar dryer with thermal storage that uses water and waste engine oil as the working medium at flow rates of 0.035, 0.045, and 0.065 l/s. A parabolic trough collector was used to collect heat, which was then stored in a thermal energy storage device. The system consisted of rectangular boxes containing stearic acid phase change materials with 0.3vol % Al₂O₃ nanofluids, which stored heat for the waste engine oil medium is 0.33 times that of the water medium at a rate of flow of 0.035 l/s which was also higher than the flow rates of 0.045 and 0.065 l/s. The parabolic trough reflected solar radiation to the receiver, and the heat was collected in the storage medium before being forced into circulation and transferred to the solar dryer. At a flow rate of 0.035 l/s, the energy output of the solar dryer’s waste engine oil medium and water was determined to be roughly 12.4, 14, and 15.1, and 9.8, 10.5, and 11.5 times lower than the crops output of groundnut, ginger, and turmeric, respectively. The energy output in the storage tank and the drying of groundnut, ginger, and turmeric crops with water and waste engine oil medium at varied flow rates of 0.035, 0.045, and 0.065 l/s were studied. Finally, depending on the findings of the tests, this research could be useful in agriculture, notably in the drying of vegetables.

The intermittent nature of solar radiation requires a thermal energy storage (TES) system for reducing the mismatch between energy demand and supply. Solar water heating (SWH) systems can help save up to 90% of the utilized energy for water heating. In this study, a compound parabolic concentrator (CPC) solar collector has been coupled to three different configurations of TES system. A comprehensive analysis on the effects of PCMs arrangements in TES systems viz three PCMs (case 1) and five PCMs (case 2) on the energy efficiency, exergy efficiency, and overall loss coefficient of the solar collector and TES system has been made and compared with sensible TES system. An experimental data showed an augmented energy storage of 12% and 41% in “case 1” and “case 2” over sensible TES system as a result of reduction in heat losses with the cascaded arrangement of PCMs. The collector paired with case 2 configuration clearly exhibited a higher exergy efficiency due to supply of heat transfer fluid at relatively lower temperature while compared to other TES configurations. The outcomes of this study reveal the key role of cascaded arrangement of PCMs for enhancing energy and exergy efficiencies of solar collector.

Solar cells convert a part of the solar irradiance into electrical energy, and the remaining produces heat, which can be converted as a thermal energy accumulated in the module. This conversion depends on the solar cells temperature. Since conversion efficiency is very low, 5–20%, this investigation proposes an optimal combination of a photovoltaic module with a specially designed heat exchanger in order to improve the conversion energy efficiency. So, an experimental prototype of a photovoltaic thermal collector, with a special heat exchanger design for a PV module square surface is built and tested outdoor. The system is constituted of a PV module with square surface and a heat exchanger with a copper tube, in a spiral form. In order to assess the effect of the exchanger design on hybrid system performance, a comparison with a traditional photovoltaic module is done. During the experimental tests, various parameters were measured, such as solar irradiance, ambient temperature, coolant inlet/outlet temperature and surface temperature of the device. Based on the obtained results, it has been found that the use of the new PVT decreases the PV cells temperature in the order of 20°C. A consequence of that shows that the electrical power increases, by 6 W; moreover, the electrical energy efficiency goes from 7.93 to 9.65%, while the thermal energy efficiency of the PVT reaches 74.3%. The overall energy efficiency for the same system achieved was 84 %. Therefore, the energy loss is minimized, reaching 16%.

The photovoltaic (PV) for irrigation system is an emerging technology to harness the solar energy. The performance of the PV modules depends on the incident solar radiation, geographical location, and the surface temperature of the modules. The performance of the PV system needs to be monitored by manually or embedded controllers. The commercially available technologies for monitoring the system are costlier and need to be optimized. The Arduino controller is used to monitor the performance of the photovoltaic (PV) system in Coimbatore (11.016° N, 76.9558° E), Tamilnadu, India. The PV surface temperature is monitored and controlled by flowing the water above the module by setting the mean ambient temperature as a reference temperature 34 °C when the system exceeds the reference temperature. PV surface temperature is reduced up to 16°C thus improved the electrical efficiency by 17% compare to the reference module. The Arduino controller control the relay to switch on the motor to control the mass flow rate of the water at 0.0028kg/s. The various parameters are measured such as voltage, current, and solar radiation of the location and analyzed. The estimated cost of monitoring system and various sensor is 10$ which cost comparatively 50% lower than the other PV monitoring controllers. This method can be employed in the medium and large-scale irrigation system.