Research on the size optimization of photovoltaic panels and integrated application with Chinese solar greenhouses

Currently, two main problems in the research of greenhouse and photovoltaic integrated applications exist: the photovoltaic board design is not driven by agricultural production demand, and an appropriate research model is lacking. Here, a sky illumination model is proposed that can not only explain greenhouse daylighting but also address the problem of photovoltaic shading. An optimal design scheme of grid photovoltaic panels to replace large photovoltaic panels is proposed, and the integrated application effect with Chinese solar greenhouses is simulated. Results showed that (1) the shading effect of a single photovoltaic strip with an appropriate width at a certain height above the ground was so small that it could nearly be ignored. (2) Such photovoltaic panels were arranged in grids at select intervals, and with an increased spacing width (from 0 to 20 cm), the light transmittance increased gradually (from 0 to 90%). (3) To integrate the grid photovoltaic panels with Chinese solar greenhouses, they did not completely block the sunlight, so they did not severely affect the greenhouse daylighting. The layout of such photovoltaic panels can be well adapted to Chinese solar greenhouse, and the scheme and the model can also be widely applied to other types of greenhouses.