Released September 28, the 11th annual American Council for an Energy-Efficient Economy (ACEEE) State Energy Efficiency Scorecard provides information on how states rank in terms of their energy efficiency efforts, including those that are the most improved.

Rankings are based on the strength and performance of efficiency policies and programs and on best practices and leadership in energy efficiency.

Tied for first place last year with California, Massachusetts now holds the number one position, with California dropping to second place, followed by Rhode Island, Vermont, and Oregon in the top five.

"As Massachusetts continues to make historic investments and progress in clean energy development, energy efficiency remains the most cost-effective method of reducing ratepayer costs and lowering greenhouse gas emissions," said Charlie Baker, governor of the state, in response to its number one ranking in the ACEEE scorecard.

The three most improved states are Idaho (jumping from No. 33 to No. 26), Florida and Virginia. The other most improved states in the top 10 are Oklahoma; Utah; Nevada; Louisiana; Oregon; Washington, D.C.; and Oregon.

"Idaho is committed to using energy and all our precious resources in the most efficient way possible," said Butch Otter, governor of the state, in response to its "most improved" status in the ACEEE scorecard. "The ACEEE report shows that we're making real progress in capturing cost-effective energy efficiencies, which help reduce power bills for ratepayers and the need for more costly and less sustainable forms of energy generation."

While not one of the top 10 most improved states, as Florida was, Texas was another much-improved state.

"States hit by Hurricanes Harvey and Irma will need to rebuild, and energy efficiency can help them do so smartly, including improved building codes and promotion of combined heat and power systems," said Steven Nadel, executive director of the ACEEE. "By pursuing energy efficiency policies, states can save residents and businesses billions in the long term. There is a lot of overall movement in the 2017 scorecard. Some states that have gone years without much change, and others have made incredible strides."