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EPA Issues Final Rule on Stationary Compression Ignition Engines to Provide Affordable, Reliable Energy to Remote Alaskan Communities with Support of Alaska Delegation

Amendments expected to reduce particulate matter emissions by 80%

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WASHINGTON (Oct. 30, 2019) — Today, the U.S. Environmental Protection Agency (EPA) issued a final rule to revise the New Source Performance Standards (NSPS) for Stationary Compression Ignition (CI) Internal Combustion Engines. Amending the standards will increase energy affordability and reliability in remote Alaska. It is also expected to improve air quality by reducing particulate matter (PM) by approximately 80%.  

“EPA is delivering better air quality for all Alaskans by modernizing regulations to meet their needs while protecting human health and the environment,” said EPA Administrator Andrew Wheeler. “Thanks to leadership from Senators Murkowski and Sullivan and Congressman Young, our new rule supports the use of affordable, reliable energy sources that we know work in Alaska’s arctic climate.”

“Having operated utilities in rural Alaska for over 25 years, I know firsthand that power reliability challenges are significant even without more stringent regulations. Today’s commonsense approach will allow utilities to provide power more reliably while ensuring older units can be replaced with newer more efficient diesel engines. This is a success story for rural communities operating off the grid,” said Regional Administrator Chris Hladick.

“When I’m back home in Alaska, I have a firsthand look at how the EPA can impact our state, from restoring contaminated sites, to ensuring clean drinking water, and now helping communities have greater access to more affordable, dependable energy. I appreciate Senator Sullivan and Congressman Young for their leadership on this issue and the EPA for recognizing that a one-size-fits-all method isn’t workable for our state. These new regulations will make much-needed progress towards enabling Alaskans to lower the costs of their energy bills,” said Senator Lisa Murkowski (R-AK). “This is significant, long-awaited news for the remote communities and villages in Alaska that rely on these generators to keep their homes warm and the lights on.”

“I want to thank the Trump administration and EPA Administrator Wheeler for working with us, not against us, to ensure Alaskans have access to the energy that they need,” said Senator Dan Sullivan (R-AK). “This implements my remote generator bill that was signed into law last month to allow Alaskans to power their homes reliably without having to incur crippling costs caused by unnecessarily burdensome federal regulations. I hope we can continue to work with EPA to provide regionally appropriate requirements and reliable, affordable energy for Alaskans living in remote communities.”

“Today’s announcement by the EPA is a great victory for our remote Alaskan communities,” said Congressman Don Young (AK-AL). “Many Alaskans depend on diesel generators to heat their homes, run their appliances, and keep their lights on, and Washington D.C. shouldn’t be getting in the way of their everyday lives. Quite frankly, new generators are very costly, and families shouldn’t be burdened by an arbitrary decision made four thousand miles away. I thank Administrator Wheeler for his hard work in issuing this final rule.”

Today’s rule satisfies the agency’s obligation to revise the rule under the recently enacted Alaska Remote Generator Reliability and Protection Act, which was signed into law by President Trump on Oct. 4, 2019.

Remote communities in Alaska rely almost exclusively on diesel engines for electricity and heat – especially in winter when these engines need to be reliable. Due to limited access to these remote communities, the costs of operating these stationary CI engines, which include acquiring and installing aftermarket controls required by the NSPS, are greater than in the rest of the United States.

There are concerns about the reliability of the aftermarket controls required by the NSPS as they were not tested in remote arctic climates. To assist remote areas of Alaska in meeting their energy needs in an affordable and reliable manner and to prevent the possible failure or loss of electricity in these remote arctic communities, revisions to the NSPS are necessary.

This action revises the PM emission standard for new stationary CI engines (2014 model year and later) located in remote areas of Alaska to meet the Tier 3 standard. This amendment will allow these engines to comply with the rule without having to add a diesel particulate filter to newly installed engines. In 2011, EPA revised the rule to remove the requirement for these engines to meet the Tier 4 standards for other pollutants. Tier 3 engines reduce PM emissions by approximately 80% over current in-use engines.

This final rule allows remote areas of Alaska to meet the NSPS by installing new Tier 3 engines rather than more complex Tier 4 engines. Although Tier 4 engines achieve better emissions performance through the use of filters, these filters require additional maintenance and supplies for the engines to function properly, and these maintenance and supplies may not be available in remote arctic areas. Given that these engines are crucial to support life during harsh winters in these areas, the ability of the engines to function reliably under those conditions is extremely important. Contrary to EPA's expectations in 2006, the use and reliability of the Tier 4 engines have not been demonstrated in extreme conditions. Therefore, EPA is determining that Tier 3 compression ignition (diesel) engines are the best system of emission control available in remote areas of Alaska.

To learn more about the final rule, please see: