A Comparison of Fuel Cell and Energy Storage Technologies' Potential to Reduce CO2 Emissions and Meet Renewable Generation Goals

Abstract

California’s Climate Change Scoping Plan identifies fuel cell and energy storage technologies as potential strategies to support greenhouse gas emission reduction goals. It is important to understand the potential effectiveness of these technologies in meeting the State goals. To this end, scenarios were examined using the HiGRID model, comparing the deployment of 5 GW of fuel cells to pumped hydro, compressed air, and flow battery storage. Cases were run for the California electricity grid at 33% and 50% renewable energy, and each scenario was evaluated based on carbon reduction potential and cost per ton carbon dioxide equivalent reduced. Fuel cell scenarios showed greater emissions reductions compared to energy storage for all cases and lower cost per ton CO2 reduced for all cases, except for pumped hydro at 50% renewables. As renewable levels increase, so does the reliance on new peaker capacity, slightly undermining emission reduction gains from fuel cell deployment. Dynamic, energy storage technologies, on the other hand, minimize new peaker capacity at high renewable levels, alluding to a greater opportunity for utilizing energy storage in the long term. While the most cost-effective energy storage technology is pumped hydro, the feasibility of large-scale deployment of pumped hydro is unclear due to the current California drought and the on-going threat of climate change. Of the technologies studied, high-efficiency baseload fuel cells show the greatest potential to support CO2 reduction goals in the near term, with the grid benefiting from more dynamic dispatch at higher renewable levels.