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The present study summarizes two growing seasons (2020–2021) of microclimate characterization and vegetable crop growth in an agrivoltaics system in northern Colorado, USA. The replicated experiment evaluated three module transparency types (opaque silicon [0 % transparent], bifacial silicon [∼5 % transparent], and semi-transparent cadmium telluride [40 % transparent]) plus a full sun control, and four vegetable crop species (summer squash, peppers, tomatoes, and lettuce). Air temperature under the modules in July was approximately 0.5 °C cooler than in the full sun. Soil temperature (2.5 cm depth) maximum differences were more pronounced and were 5.8 °C, 9 °C, and 14.4 °C cooler under bifacial, semi-transparent, and opaque silicon, respectively. For summer squash growing directly under the solar modules, yield was significantly reduced under each of the module transparency types. However, there was no statistically significant yield reduction for peppers, tomatoes, and lettuce indicating their suitability in an agrivoltaics system. The numerical yield of most crops increased as the transparency of the solar modules increased, which could be the focus on future work.

There are many benefits to producing insects for food and feed; they require fewer resources to produce, process, and distribute. The digested and undigested waste along with insect feces (i.e., frass) from the mass production of insects can be considerable. Black soldier fly larvae (BSFL) digestion of organic residue produces frass that is high in macronutrients that are desirable for plants, potentially serving as a partial replacement for fertilizer or growing media, such as peat. Arugula and lettuce were grown in greenhouse pot studies with treatments comprised of BSFL frass (BSF), vermicompost (VC), and peat, and compared to a 100% peat control (CP). Yield, productivity, greenness, and tissue nutrient concentrations were measured. Arugula and lettuce produced the highest fresh weight and dry weight in the BSFL treatments. Primary macronutrients (N, P, K) and Mg in both crops were also highest in the BSFL treatments. Secondary macronutrients (Ca, Mg, S) and micronutrients produced more variable results (B, Fe, Mn, Cu, Zn). Lettuce produced larger yields but had much lower concentrations of nutrients compared to arugula. In small amounts, 10–20%, BSFL frass can serve as a good replacement for peat in leafy green crops. It is an especially beneficial way to recycle organic side streams in different industries and reduce waste production overall.

Agrivoltaics (APV), the co-location of agriculture and photovoltaics (PV), addresses an inherent competition for land usage. Taking the same dual-use concept to the urban landscape, rooftop APV can provide locally grown food in areas of need while providing distributed energy generation. In this multi-year investigation, different APV plots in northern Colorado, USA, were studied for crop metrics, light transmission, air temperature, soil/substrate temperature and moisture. Crops were grown under different solar panel types including opaque silicon and opaque and semi-transparent (ST) thin-film CdTe technologies. Growth conditions were characterized showing generally improved conditions and moderated temperatures under the panels. The ST-CdTe panels had increased photosynthetically active radiation (PAR) compared to both opaque panel types without a significant corresponding increase in temperature.