Grid-Scale Life Cycle Greenhouse Gas Implications of Renewable, Storage, and Carbon Pricing Options

Abstract

Models that characterize life cycle greenhouse gases from electricity generation are limited in their capability to estimate emissions changes at scales that capture the grid-scale benefits of technologies and policies that enhance renewable systems integration. National assumptions about generation mixes are often applied at annual time steps, neglecting spatiotemporal resolutions that provide insights on impacts from time-variable emissions. Our grid-scale model incorporates details of transmission and generation planning that allows a geographically and temporally textured and more realistic assessment of the life cycle greenhouse gas emissions outcomes, using a case study of the Western Interconnection of North America. Results from a co-optimized model of generation, transmission, and operationsthe Johns Hopkins Stochastic Multistage Integrated Network Expansion Modelprovide a detailed characterization of twenty-one scenarios with different configurations of storage additions, new renewable capacity, and carbon prices. Life cycle results suggest that optimization models that focus on generation alone may underestimate emissions by 18−29% because only emissions from power generation are quantified (i.e., supply chain emissions are omitted) but also that carbon pricing is the predominant driver of reducing emissions in the scenarios we examine. Life cycle assessment of electricity generation should move beyond individual technologies toward capturing the influence of policies at the system level to better understand technology-policy dynamics for the grid.

Expanding carbon neutrality strategies: Incorporating out-of-boundary emissions in city-level frameworks

“…New industrial and economic development opportunities are essential drivers of those stakeholders. Since scope 3 emissions occur outside the administrative boundaries of cities, broader coordination among higher levels of governance (e.g., regional, national, international) is required for net-zero consumption emissions, especially for systems that operate on a larger scale, such as the power grid [ 71 ]. Collaborative initiatives like the Covenant of Mayors can provide a valuable platform for small-sized cities to engage in collaboration across different levels of government [ 72 , 73 ].…”

Overcoming barriers to improved decision-making for battery deployment in the clean energy transition

“…The integration of electric grid dynamics and LCA of energy storage is starting to occur in the research literature, notably in studies for the French electricity system 48 and for the US Western Interconnect. 49 However, this practice is somewhat nascent with many methodological uncertainties remaining and is not yet being implemented into decision-making for battery deployment or energy systems planning.…”

“…Regular integration of these capabilities, along with the development of agreed-upon standards for how this integration is accomplished, more accurate characterization of the use phase of battery systems to the level needed for more confident decision-making. While this practice is starting in the research literature, 48 , 49 more development and widespread practice is needed to mature these methods for use by decision-makers. Open data on electricity generation, but also energy system models are increasingly available for many countries.…”