Affordable Clean Energy Rule

The Affordable Clean Energy rule (ACE) was issued in June 2019, as a replacement for Obama’s regulation plan, the Clean Power Plan (CPP), which was issued in 2015. ACE provides companies that use coal-fired electric utility generating units, or EGUs, with reasonable criteria for decreasing greenhouse gas emissions, compared to the CPP’s harsh regulations. Under the CPP, states were required to create their own plan to reach the requirements; and if a state failed to create a plan, the EPA would make one for them. With ACE, unlike the CPP, there are reasonable requirements for companies to meet that will not come with a hefty price tag for companies or Americans.

The CPP was introduced in 2015, and it was Obama’s goal through this plan that carbon emissions would be reduced by 30% compared to 2005. In the CPP, there were conditions for companies to meet regarding carbon emissions, but President Trump said that this plan, joined with the Paris Climate Agreement, would negatively affect America’s manufacturing and coal industries. Criticizers of the CPP argued that the energy costs for Americans would be increased considerably. Texas would be impacted the most by these costs, because in 2016, Texas led the country in carbon emissions with 653.8 million metric tons. ACE is projected to reduce carbon emissions by 11 million tons, or about 0.6%, by 2030. Although this may seem miniscule, combined with industry trends the carbon emissions will decrease by 35% by 2030.

One of the emission guidelines that is being implemented by ACE is heat rate improvement (HRI) as the best system of emissions reduction (BSER) for carbon dioxide  from coal-fired EGUs. Heat rate is used to measure the amount of energy needed to produce a unit of electricity. After applying many HRI technologies and techniques, EGUs will be able to generate electricity more efficiently, and with less carbon emissions. The BSER, which in this case is HRI, is the best available technology or other method that has been shown and proved to improve emission performance for a certain industry or procedure. When the EPA considers the BSER, they take into account the cost, feasibility, environmental impact, non-air quality health, and energy requirements of introducing the BSER.

ACE lists six HRI “candidate technologies,” along with other operational and maintenance practices. These six HRI candidate technologies are: Neural Network/Intelligent Sootblowers, Boiler Feed Pumps, Air Heater and Duct Leakage Control, Variable Frequency Drives, Blade Path Upgrade, Redesign/Replace Economizer. For all of these technologies, EPA has provided information about the carbon emission reduction that would be achievable. The technologies were chosen for their ability to be applied broadly and they are expected to deliver noteworthy HRI without restrictions due to geography, fuel type, etc. After researching the applicability of the six candidate technologies to their current sources, states will send their plans to the EPA that should establish a standard of performance and measures that provide for the implementation and enforcement of such standards. These plans are due in three years.


For more information, you can find the EPA landing for ACE here,

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Contributed by Sarah Breithaupt, Marketing Intern