Biodiversity impact of the consumption of peat and wood-fired district heating

Abstract

The use of biofuels is becoming an increasingly important part of national and corporate climate strategies. At the same time, the consumption-based biodiversity impacts of biofuels are generally poorly known. Here we used a consumption-based approach to assess the biodiversity impacts of peat and wood-fired district heating in Finland. We combined the information on the area of impacted ecosystems and their condition before and after the impact to evaluate the impact as habitat hectares, i.e., the loss in the condition of the impacted habitats. The habitat hectare approach has not been used in previous studies on consumption-based biodiversity impacts but could be replicated to assess biodiversity impacts in different contexts around the globe. We present an eight-step general protocol for such assessment and discuss the usability of the protocol in assessing consumption-based biodiversity impacts of district heating systems. Considering different fuel types, peat had the highest biodiversity impact per unit area, followed by chips from roundwood and logging residue chips. If we consider the impacts per unit energy, chips from roundwood had the highest and peat the lowest biodiversity impact. We conclude that it is possible to assess biodiversity impacts of raw material-based consumption, like we did in our example case. This protocol should be further developed and refined in different systems and with different raw materials.