Effect of combustion technology and biogenic CO2 impact factor on global warming potential of wood-to-heat chains

In this work wood-to-heat chains are assessed on environmental and micro-economical aspects. Wood combustion produced various minor pollutants, which should be considered in life cycle assessment. For this purpose different wood combustion processes have been modeled under Aspen Plus® software in order to assess pollutant emissions (CO2, aromatic compounds, CO, etc.) based on industrial emission data and therefore to obtain a rigorous life cycle inventory. Different technologies are assessed for a fixed heating demand and hot water production of a typical French house: district heating fueled by wood chips, individual stoves or boilers fueled by wood logs or pellets. Electricity, natural gas, and fuel oil solutions complete the scenario set. The different heating solutions are compared in terms of their greenhouse gas emissions and of the cost of the final energy (including investment and operating costs). The important effect of minor pollutants (such as CO and volatile organic compounds) on the global warming potential of wood-to-heat chains is highlighted. The performance of wood scenarios compared to fossil-based ones is also highly dependent on the impact factor assumed for the biogenic CO2. The wood-based scenarios present a wide range of costs with pellet solutions being more expensive on investment and pellet production.