In order to effectively integrate renewable energy sources such as biomass into New York State’s electricity market, industry leaders and policymakers must have access to accurate information about the potential supplies of biomass. Particularly, they require information on biomass resources that are currently available so that these resources may be used efficiently in the production of electricity through cofiring in existing coal-fired power plants. This technology has the potential to utilize renewable energy sources and reduce greenhouse gas emissions in the near future. This project seeks to estimate and map the supply of different sources of biomass through New York State in order to remedy the current lack of information available on this topic. Herbaceous energy crops, represented by switchgrass, and short-rotation woody crops, represented by willow, are considered as potential alternative feedstocks. Supplies are estimated based on land potential, land constraints, economic factors, and power plant capacities. GIS is used to map these factors. Varied scenarios are analyzed and discussed to illustrate a range of potential outcomes. The least intensive production scenario predicts a potential supply greater than the cumulative capacities of all power plants for cofiring. All other scenarios predict that production can meet capacity in more concentrated areas near power plants. This study finds that New York State has the resources to cofire biomass at all of its coal-fired power plants in the short-term.