Aurinkosuo - Energy production, climate impact and profitability of cultivating short-rotation energy crops and producing solar power in former peat extraction areas in Northern Savonia

With the phase-out of peat energy use in Finland, peat extraction activities are coming to a halt, releasing large areas from production each year. These former peat extraction areas (cut-away peatlands), are a significant source of greenhouse gasses (GHGs), emphasizing the need for their rapid repurposing. Solar power production stands as a compelling after-use option for landowners as it offers steady rental income without requiring substantial initial investments. Cut-away peatlands are inherently suitable for solar power production, given their prior human intervention. Traditional land use practices, such as cultivating short-rotation crops (e.g., hemp, willow, downy birch, reed canary grass) for bioenergy, also remain viable alternatives for reutilizing cut-away peatlands. However, their markets are evolving rapidly due to the emergence of novel products like bioplastics, composite materials, and biocoal, which are replacing conventional materials. Additionally, there is an urgent need to identify safe and cost-effective substitutes for peat as a growth medium. Typically, cultivating short-rotation crops has a cooling effect on the climate. Nevertheless, a comprehensive assessment of climate impacts must consider the entire life cycle, encompassing factors like the size and longevity of carbon storage in the final product and emissions stemming from agricultural and industrial practices. Currently, the climate impact of various after-use options (including solar power) for former peat extraction areas remains unknown and, consequently, uncontrollable. The Aurinkosuo -project aims to attain a comprehensive understanding of the climate impact and financial performance of diverse value chains associated with the after-use of former peat extraction areas. Additionally, we are exploring which annual plant species can thrive beneath solar panels and whether they promote carbon sequestration and affect the fire risk of cut-away peatlands. An experimental field will be established in a former peat extraction area, investigating various land-use options (solar power field, solar power field with vegetation, cultivation of short-rotation energy crops with and without biocoal). Intensive field measurements will assess soil greenhouse gas emissions (CO2, N2O, CH4), and biomass production of short-rotation energy crops. A life cycle assessment will elucidate the climate impact of complete value chains. Financial analysis will investigate the profitability of different options, supporting workforce employment and enabling informed land use decisions by landowners. Society at large stands to benefit from a more efficient allocation of public resources.