(49c) Estimating the Greenhouse Gas Emissions Payback Period of Planned Offshore Wind Energy Using Multiregional, Environmentally Extended Input-Output Analysis

There is a substantial projected increase in energy generation from offshore wind farms in the US over the next three decades due to an increase in legislative commitments and funding from federal and state governments. Achieving ambitious offshore wind targets will be dependent on the expansion of domestic manufacturing and significant transfers of knowledge from world leaders in this technology. Offshore wind energy will provide GHG emissions-free energy during the use phase of the farm, but project construction is associated with significant environmental impacts that are less commonly acknowledged, which offset the touted benefits to a degree. Furthermore, offshore wind energy will be a competing technology for advanced energy materials. Developing offshore wind as a reliable domestic energy source demands a multiregional impact assessment of the economic and environmental spill-over effects of constructing offshore wind farms in major lakefronts and coastal regions. Despite the current lack of commercially operating offshore wind farms in the US, seven states have announced cumulative capacity commitments of over 28 GW by 2035. In this study, the spatial economic impacts of planned projects are estimated by combining the NREL Jobs and Economic Development Impact (JEDI) model for offshore wind energy with a multiregional input-output (MRIO) model of the United States built with the Virtual Industrial Ecology Laboratory (IE Lab). We also use a newly developed multiregional GHG emissions dataset for the US IE Lab to estimate the supply chain emissions of constructing and installing the offshore wind projects. These emissions estimates provide a more complete understanding of the time it will take for proposed cleaner energy projects to offset the environmental impacts of their manufacture and installation compared to those from energy generated from fossil fuel combustion. The multiregional framework will also be used to identify which states may see the largest spill-over effects in terms of emissions generation and economic activity required to support offshore wind projects.