Following the launch of the Clean Power Plan, concerns were raised about how adding renewable energy to the grid would affect reliability. According to a new report conducted by The Brattle Group, compliance is unlikely to materially affect reliability.  The report finds, “The combination of the ongoing transformation of the power sector, the steps already taken by system operators, the large and expanding set of technological and operational tools available and the flexibility under the CPP are likely sufficient to ensure that compliance will not come at the cost of reliability.

Report lead author Jurgen Weiss PhD, senior researcher and lead author said that while the North American Electric Reliability Corporation (NERC) focused on concerns about the feasibility of achieving emissions standards with the technologies used to set the standards, they did not address several mitigating factors. These include:

• The impact of retiring older, inefficient coal plants, due to current environmental regulations and market trends, on emissions rates of the remaining fleet;
• Various ways to address natural gas pipeline constraints; and
• Evidence that that higher levels of variable renewable energy sources can be effectively managed.

“With the tools currently available for managing an electric power system that is already in flux, we think it unlikely that compliance with EPA carbon rules will have a significant impact on reliability,” reported Weiss.

In November 2014, NERC issued an Initial Reliability Review in which it identified elements of the Clean Power Plan that could lead to reliability concerns. Echoed by some grid operators and cited in comments to EPA submitted by states, utilities, and industry groups, the NERC study has made reliability a critical issue in finalizing, and then implementing, the Clean Power Plan. These concerns compelled AEE to respond to the concerns by commissioning the Brattle study.

“We see EPA’s Clean Power Plan as an historic opportunity to modernize the U.S. electric power system,” said Malcolm Woolf, Senior Vice President for Policy and Government Affairs for Advanced Energy Economy, a business association. “We believe that advanced energy technologies, put to work by policies and market rules that we see in action today, will increase the reliability and resiliency of the electric power system, not reduce it. This report from The Brattle Group confirms that the Clean Power Plan can be implemented without reliability concerns.”