Howard J. Herzog

May 15, 2024 | pubs.rsc.org | Edward Graham |Moataz Sheha |Dharik S. Mallapragada |Howard J. Herzog

Optimization of a combined power plant CO2 capture and direct air capture concept for flexible power plant operation Deployment of carbon capture and storage (CCS) equipped fossil fuel power plants on the supply-side and direct air capture (DAC) technologies on the demand side can address the dual challenge of lower carbon emissions while providing grid flexibility.

May 10, 2024 | nature.com | Bryan K. Mignone |Leon E. Clarke |James A. Edmonds |Angelo C. Gurgel |Howard J. Herzog |Jeremiah Johnson | +8 more

Energy transition scenarios are characterized by increasing electrification and improving efficiency of energy end uses, rapid decarbonization of the electric power sector, and deployment of carbon dioxide removal (CDR) technologies to offset remaining emissions. Although hydrocarbon fuels typically decline in such scenarios, significant volumes remain in many scenarios even at the time of net-zero emissions. While scenarios rely on different approaches for decarbonizing remaining fuels, the underlying drivers for these differences are unclear. Here we develop several illustrative net-zero systems in a simple structural energy model and show that, for a given set of final energy demands, assumptions about the use of biomass and CO2 sequestration drive key differences in how emissions from remaining fuels are mitigated. Limiting one resource may increase reliance on another, implying that decisions about using or restricting resources in pursuit of net-zero objectives could have significant tradeoffs that will need to be evaluated and managed. Assumptions about the use of biomass and CO2 sequestration drive key differences in how emissions from remaining fuels are mitigated in net-zero energy systems, with potentially significant tradeoffs that will need to be evaluated and managed.