The use of fossil fuels to heat greenhouses results in a substantial carbon footprint. This study uses life cycle assessment to quantify and analyze the carbon footprint of greenhouse tomato production in six regions of Switzerland, considering four non-fossil-based heating strategies: (1) wood chips boiler, (2) heat from biogas Combine Heat and Power (CHP) system, (3) waste heat recovery systems (direct and Organic Rankine Cycle (ORC) integrated), and (4) heat pumps.
The results are compared with two conventional fossil-based strategies, including (5) natural gas boilers and (6) natural gas CHP for two greenhouse scheduling practices (with and without winter months). Spatiotemporal modeling was employed to estimate heat and supplementary lighting demand of the specific regions. The results show the importance of non-fossil heat strategies that generate electricity in addition to providing heat for greenhouses. Biogas CHP (−1.69 to −0.20 kg CO2 eq./kg crop) and waste heat ORC systems (0.26–0.47 kg CO2 eq./kg crop) show the lowest carbon footprint of tomatoes in each region. As expected, all non-fossil fuel strategies (−1.69 to 0.83 kg CO2 eq./kg crop) result in lower carbon footprints than fossil fuel strategies (1.08–2.28 kg CO2 eq./kg crop). Also, all non-fossil fuel strategies (excluding heat pumps) can compete with the carbon footprint of unheated greenhouse crops imported from Spain, Morocco, and Italy.
The findings offer a roadmap for environmental policymakers on the technological impacts on greenhouse production and the influence of plant scheduling on environmental impacts.
Solgi, H., Rezaei, F., Burg, V., & Roshandel, R. (2025). Carbon footprint analysis of non-fossil heating strategies for agricultural greenhouses in Switzerland. Energy Conversion and Management: X, 101304. https://doi.org/10.1016/j.ecmx.2025.101304
Source: Science Direct
