Deep decarbonization of the energy system over the course of this century is a prerequisite to averting the worst consequences of climate change. Many decarbonization pathways have been proposed, most of which envision a substantial expansion in the deployment of variable and intermittent renewable energy sources, mainly solar and wind power. What is new in more recent climate and energy models has been an increase in the likelihood that net negative emission technologies will be required to achieve the targets enshrined in international climate accords, whether the target is a 2°C or 1.5°C rise in average global temperature.
To achieve this carbon removal, models employ a singular technology—bioenergy with carbon capture and sequestration (BECCS)—the scalability and environmental impacts of which remain uncertain. On the other hand, solar and wind power have both proved scalable: over the past decade, decreasing costs and strong government incentives have propelled a more than fifty-fold increase in installed solar power capacity worldwide, from 9 gigawatts (GW) globally in 2007 to 500 GW in 2018. Installed wind power capacity has increased more than six-fold over the same period. Concurrently, however, several major electricity markets have also seen an increase in both solar and wind power curtailment—the shutting down of electricity production from these generators because the system cannot integrate it. In the first four months of 2018, the California Independent System Operator (CAISO) was forced to curtail more than 210 Gigawatt hours of wind and solar power, and CAISO is expecting these levels of curtailment to increase as more renewables are installed in pursuit of the state’s ambitious renewable energy goals. This curtailment reduces generator availability and revenue; on the level of the system, it adversely impacts both power system reliability and generation expansion planning.
We are laying the groundwork for a new stream of research that investigates the extent to which the large-scale deployment of solar and wind power can encourage complementary carbon removal by other means. Specifically, we analyze how to transform curtailment risks into benefits by describing the extent to which curtailed electrons could power a suite of technologies that could amplify emissions reduction.