U.S. President Barack Obama speaks to the media after meeting with House Speaker John Boehner at the White House, March 1, 2013 in Washington, DC. (Photo by Mark Wilson/Getty Images) (Mark Wilson/Getty Images)

After a wait of nearly two years, the Energy Department proposed two major energy efficiency rules Thursday for commercial refrigeration equipment and walk-in coolers and freezers.

The rules represent one of the Obama administration's first steps to address climate change through its executive authority since the president announced his climate action plan in June.

Environmentalists and some lawmakers had pressed the Energy Department to issue the proposals on refrigeration equipment and walk-in coolers and freezers — which had been pending at the Office of Management and Budget for more than a year and-a-half and nearly two years, respectively — for months. The proposals have a significant environmental impact because of the size of the appliances involved: the first rule applies to equipment such as restaurant-size fridges or the deli case at a convenience store, while the second applies to the milk display case in a supermarket.

In a blog post published Thursday afternoon, Heather Zichal, deputy assistant to the president for energy and climate change, described energy efficiency as "one of the clearest and most cost-effective opportunities to save families money, make our businesses more competitive, and reduce greenhouse gas emissions."

Over the next 30 years, Zichal estimated, the two rules could cut Americans' energy costs by $28 billion and reduce the nation's carbon dioxide emissions by over 350 million metric tons. Commercial refrigeration equipment will become roughly 15 percent more efficient under the proposed standard, according to the Energy Department.

"This reduction in CO2 emissions would be the equivalent of taking nearly 109 million new cars [off] the road for one year," she added. "Or put another way, the energy saved from these proposed rules would be equal to the amount of electricity used by 50 million homes in a year."

Sen. Sheldon Whitehouse (D-R.I.), who had sent a letter along with his colleagues to OMB in early June questioning the delay in issuing the rules, praised the agency's director Sylvia Matthews Burwell and its Office of Information and Regulatory Affairs administrator Howard Shelanski for "dislodging rules like these two, that have been stuck at OMB for far too long. With Congress still paralyzed by the influence of the big carbon polluters, these are exactly the kind of actions the administration should take to fight back against climate change.”

The proposed rules will be subject to public comment for 60 days before the agency can finalize them.