Download the 2024 NOx Report here
Regenerate California, a coalition led by the Sierra Club and the California Environmental Justice Alliance, commissioned a study on the emission of nitrogen oxides, or NOx, from gas-fired power plants as part of their efforts to transition California away from fossil fuels and toward 100% renewable energy. NOx emissions are proven to contribute to smog and other severe public health harms, including asthma, respiratory illness, and increased rates of hospitalization. Nine gas plants were identified as at risk of violating national air quality standards.
The Worst Offender: Walnut Creek
Walnut Creek Energy Park has repeatedly shown levels of NOx that are close to or above national air quality standards. The Census Tract in which the plant is located is predominantly Hispanic (80.8%) and is one of the most severely polluted in the state. The community that experiences the most NOx emissions from this power plant is about 1.2 miles southwest of the plant. It’s a residential community with two elementary schools. There is also a nearby railroad, numerous warehouses, and the 60 freeway. These cumulative impacts likely contribute to the NOx emissions in the area.
Key Findings:
- Public access to information and emissions data from California gas plants is limited due to gaps in reporting and regulation.
- Gas plant emissions are at their highest during plant start-up and shutdown, when pollution controls are typically ineffective or not operational.
- NOx is not the only harmful emission coming from gas-fired power plants. Combustion in gas plants leads to formation of other pollutants, including ammonia, PM 2.5, and formaldehyde which are among the most concerning.
Key Recommendations:
- State energy agencies and utilities must reduce California’s reliance on dirty gas plants with priority for environmental justice communities.
- Regulators must support improvements in data reporting. All reporting information must be made available to the public.
- Gas plant owners and operators must be required to improve NOx emissions monitoring.
- Air quality management districts should perform further detailed analysis and investigate potential air permit violations.
- Air quality management districts should broaden impact analysis by looking at other gas plant pollutants.
As frontline communities continue to experience public health harms, including increased rates of respiratory illness, pregnancy complications, and in severe cases cancer, it is the responsibility of state and local regulators to make decisions that best protect Californians. California’s move away from dirty fossil fuels toward an equitable, clean energy future is a necessity that must center the voices and lived experiences of environmental justice communities.