Are there specific regions where utility-scale batteries are more effective at reducing emissions

Utility-scale batteries’ effectiveness at reducing emissions varies significantly by region, depending on several factors including the local grid’s energy mix, regulatory environment, market incentives, and how the batteries are operated.

Regions Where Batteries Are More Effective at Reducing Emissions

• California and Similar Regions With High Renewable Penetration
  California provides a prime example where utility-scale batteries have transitioned from causing a net increase in emissions to enabling significant net reductions. This success is largely due to batteries charging primarily on excess solar energy during the day and displacing natural gas generators during peak periods, thus reducing reliance on fossil fuels. California’s combination of ambitious clean energy targets, a large amount of installed renewable capacity (notably solar), and policy support such as the Self-Generation Incentive Program (SGIP) has cemented batteries as a key part of its pathway to 100% carbon-free electricity by 2045.
• States in the Regional Greenhouse Gas Initiative (RGGI)
  States like Connecticut, Massachusetts, New Jersey, and New York have robust storage targets aligned with 100% clean energy and greenhouse gas reduction goals. These states typically have a grid with increasing renewable penetration and strong policy frameworks, enabling utility-scale batteries to contribute meaningfully to emissions reductions.
• Regions with High Shares of Fossil Fuel Peaker Plants Flexible Enough for Displacement
  Locations where batteries can displace fossil-fuel peaker plants—often natural gas plants that operate during peak demand—can see emissions benefits. This typically requires batteries to be paired strategically with renewable generation (e.g., solar or wind) and operated with incentives that prioritize emissions reduction rather than purely economic or grid reliability services.

Regions Where Batteries May Not Reduce Emissions

• Regions With High Carbon Intensity When Batteries Charge
  Some utility-scale batteries, especially standalone ones, tend to increase emissions if they are charged predominantly with electricity from fossil fuel sources, and then discharge during periods that do not displace high-emission generation effectively. This phenomenon has been observed in many locations where the grid’s marginal generation during battery charging is coal or natural gas-heavy, and market incentives drive batteries toward non-emission-reduction services (e.g., frequency regulation or energy price arbitrage).
• Markets Lacking Carbon-Aligned Incentives
  When financial incentives reward batteries based on market prices rather than carbon emissions, batteries may optimize for revenue by charging during low-price periods even if those coincide with high-emission generation, leading to an overall increase in emissions.

Summary

Utility-scale batteries are most effective at reducing emissions in regions characterized by:

• High shares of zero-carbon renewables (especially solar and wind)
• Strong emissions reduction policies and clean energy targets
• Market designs and incentives that prioritize carbon reduction over purely economic benefits
• Coordination with renewable generation to charge on clean energy and discharge to replace fossil fuel peaker plants

In contrast, batteries in regions with carbon-intensive grids and misaligned incentives may increase emissions rather than reduce them. California and certain RGGI states exemplify the success possible when these factors align well.

Therefore, the regional context—grid carbon intensity, policy frameworks, and market designs—are crucial determinants of whether utility-scale batteries effectively contribute to emissions reduction.