Lighting Energy and Revenue Analysis in an Agrivoltaic Agrotunnel for Lettuce and Swiss Chard Production

Although the economic importance of optimizing lighting systems and energy use in indoor farming is well known, there is a notable lack of studies focusing on economic trade-off analysis between agrivoltaic and grid-powered solutions integrated into light map analysis and revenue sensitivity assessments. To address this gap, this study investigates an indoor true vertical lettuce agrotunnel. Regional, seasonal, and market type sensitivity analyses were carried out on the prices and experimental yields to calculate the revenue from lettuce production. Technoeconomic analysis indicated that agrivoltaics outperformed the grid-only power supply by net present cost and levelized cost of electricity reductions of 13.2% and 44.2%, respectively. Photosynthetic photon flux density (PPFD) and daily light integral (DLI) were compared for the cases of 41–61 cm distances between the lights and the walls. With the 20 cm distance variations, 16.6–17.8% changes in the average PPFD were achievable without increasing energy consumption. In addition, annual revenue from lettuce green mix packs ranged from $61,735 to $86,164 USD for singles and from $83,603 to $116,685 USD for multiple plants per pot strategies, depending on the variety packs. Luxury and mid-range price categories kept the return on investment above 10% at all capital cost levels. The agrotunnel achieved the maximum specific yield of >70 kg/m2/year.