Abstract
Agriculture is a major contributor to global environmental challenges and is highly vulnerable to climate change. High-technology greenhouse farming provides efficient, secure and climate-resilient food production but costs significant energy to operate. We designed and constructed a greenhouse with high-transparency photovoltaic windows used as roof- and wall-mounted components of building envelope and demonstrated its significant potential to improve the sustainability of greenhouse farming. This innovative structure reduced energy consumption by 57% and water usage by 29% in research-scale greenhouse production. We showed that several crops commonly produced in greenhouses exhibited no yield loss when grown in solar greenhouses, including tomato, snow pea, spinach mustard, dwarf bean, bell pepper and lettuce. Due to a limitation in the experimental design, solar windows were not fully installed on the greenhouse, which led to an underestimation of the potential energy savings. A computing model showed that a fully glazed solar greenhouse has the potential to offset up to 100% of the energy consumption in worldwide locations by using adaptable and efficient temperature control techniques, thereby potentially enabling completely self-sustainable greenhouse farming on a global scale. The potential of self-sustainable greenhouse farming could be further enhanced by refining its wavelength-selective transmittance and using genetic manipulation to engineer crops that thrive in the solar greenhouse environment. The solar greenhouse technology represents significant opportunities to make substantial progress towards achieving net-zero emissions in global food systems by 2050.
