A Validated Model, Scalability, and Plant Growth Results for an Agrivoltaic Greenhouse

Abstract

We developed an agrivoltaic greenhouse (a ‘test cell’) that partially trapped waste heat from two photovoltaic (PV) panels. These panels served as parts of the roof of the enclosure to extend the growing season. Relative humidity, internal air temperature, incident solar radiation, wind speed, and wind direction were measured for one year. A locally 1-D transient heat and moisture transport model, as well as a shadowing model, was developed and validated with experimental data. The models were used to investigate the effects of altering various parameters of the greenhouse in a scalability study. The design kept test cell air temperatures generally above ambient throughout the year, with the test cell temperature below freezing for 36% less of the year than ambient. Plant growth experiments showed that kale, Brassica oleraceae, a shade-tolerant plant, can be grown within the test cell throughout the winter. The simulations showed that enlarging the greenhouse will increase cell air temperatures but that powering an electric load from the PV panels will reduce cell air temperatures.