Improving the efficiency of Solar energy systems by sustainable novel methods

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In recent years, solar deployment has skyrocketed for several reasons: increased energy requirements, greater availability of incentives, lower costs, improved technology, more investment, ambitious climate targets. Combined with the high availability of solar energy, solar farms have grown larger and more widespread. The conversion of sunlight into electricity, either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP) are the most deployed methods. However, there are few shortcomings that face this industry: the relatively low energy conversion and high efficiency degradation with temperature rise. For commercial PV panels only 11-17% of incident solar radiation is converted into electricity while the remaining is converted to heat, with the efficiency decreasing further by 0.45% for every 1degree C increase in temperature.Therefore, if the PV panels can be cooled the electrical efficiency will increase. Furthermore, if the heat extracted from the PV panels can be used by another process (space heating, water heating, desalination etc) then the heat produced by the sun can also be harnessed increasing the overall efficiency of the solar energy system. Moreover, if the power demand of the system that extracts the thermal energy can be reduced the overall system efficiency is further increased. In addition, the extraction of thermal energy should be carefully controlled so there is a balance between the electrical energy and thermal energy extracted from the system to ensure the maximum overall efficiency is achieved. For example increasing fan speed will increase the electrical power demand reducing the electrical efficiency but will result in more thermal energy extracted increasing the thermal energy efficiency.