The Land and Water Implications of Biomass Co-Firing in the MISO region

Abstract

Most states in the MISO region have created State Renewable Portfolio Standards that require electric utilities to generate a certain portion of their power from renewable and clean energy sources. Accordingly, power plants need to modify their practices to meet requirement. For coal-fired power plants, biomass co-firing is considered to be a promising and efficient way to enhance the renewable portfolio, but at a lower cost and higher efficiency compared to power plants fully dedicated to biomass (IRENA 2012). Due to the high transportation cost associated with biomass feedstock, the potential for co-firing at a given coal-fired power plant depends on the local availability of biomass. In the MISO region, there are many coal power plants which are candidates for co-firing with biomass. For most of these plants, corn residue is the most available and cost-effective biomass resource. However, if there is a significant shift to co-firing with corn residue, this could have important implications for agriculture in the region, as it will increase the returns to corn production relative to other crops. This, in turn is expected to have important implications for land and water quality, as corn is relative intensive in nitrogen fertilizer use – and in some locations it is an important user of irrigation. Nitrate leaching is, in turn, a significant source of water quality degradation in the region, as well as downstream – as far away as the Gulf of Mexico (Goolsby et al. 1999). The main objective of this study is to explore the potential for biomass co-firing and the associated impacts on land and water resources in the MISO region.