Solar-Efficient Greenhouse with Electricity and Heat Generation

Controlled environment agriculture (CEA) has been used intensively worldwide to produce high quality products. One important issue associated with CEA is that temperature control of the greenhouse is often difficult to achieve, requiring large amount of fuel and/or electric power. Physical Sciences Inc. (PSI), in collaboration with the Department of Agricultural and Biosystems Engineering, The University of Arizona (UA), and Lawrence Berkeley National Laboratory (LBNL), proposes to develop a solar efficient greenhouse for controlled environment agriculture (CEA). In this system, a selective spectral reflector separates the solar spectra into two spectral regimes: (i) the photosynthetically active radiation spectra which is 42% of the terrestrial solar power; and (ii) the non-plant growing spectra (non-PAR), comprising 58% of the solar power. The PAR spectra pass through the reflector into the greenhouse while the non?PAR spectra are reflected and focused onto the Concentrated Photovoltaic (CPV) cells for electric power generation. The non-PAR power not converted to electric power will be recovered as heat by the cooling water circuit.Our overall Phase I and Phase II objective is to develop and deliver to the CEA industry a new and innovative greenhouse system which provides high quality light to the plant canopy and generates electric and thermal power to offset the cost of maintaining the greenhouse.