Electric power system utilities are engaged in work to reduce the carbon dioxide emissions intensity of electricity generation. The ultimate aim is to reach near-zero carbon dioxide emissions. Effectively mitigating climate change will require power utilities to achieve negative, not near-zero, carbon dioxide emissions though. The term, negative emissions, denotes removal of atmospheric carbon dioxide that already was emitted, and meeting this goal will require massive deployment of two key negative emission technologies: direct air capture and sequestration of carbon dioxide (DACS) and bioenergy with carbon dioxide capture and sequestration (BECCS). In DACS, sequestration is achieved through geologic, long-term storage of captured carbon dioxide in underground formations. In BECCS, energy is generated from burning fuels derived from biological sources, such as switchgrass, and the carbon dioxide produced from the combustion is again absorbed by growing new crops of this fuel source. Further research is needed into how to integrate DACS and BECCS into existing power generating systems. Robust approaches to evaluate how carbon dioxide removal via negative emissions technologies can fit into different systems are critically important. In this research project, the team will answer key questions including, how accounting for large-scale negative emission technologies integration in future power systems will affect near- or long-term decarbonization plans, and how different decarbonization and negative emission technologies integration pathways can be evaluated. Ultimately, the project will develop a novel framework driven by a power system long-term planning model and robust scenarios capturing the interactions between decarbonization of power systems and integration of negative emission technologies.
This research project has three specific research objectives: reformulate, parameterize, and validate an optimization-based capacity expansion model to be capable of integrating negative emission technologies. Then, run this capacity expansion model through an experimental design incorporating decarbonization and negative emission technologies scenarios, analyze results, and then address uncertainty through sensitivity analyses. Finally, actively communicate results with the research, education, and power systems communities. Decarbonization decisions with near-term versus with long-term negative emissions targets in mind could lead to power systems with radically different generation, storage, and transmission features. Different features, in turn, could drive divergences in cost and feasibility and, ultimately, undermine achieving climate change mitigation targets. This research project aims to create knowledge about how to ensure that near-term actions are consistent with long-term carbon dioxide removal needs and how to optimize feasibility. The project team will publish policy briefs and share analyses through the Grid School at the Institute for Public Utilities, which trains utilities personnel, regulators, and others. The team also will develop a podcast miniseries introducing and contextualizing negative emissions technologies.