what is energy star ?

ENERGY STAR® is the government-backed symbol for energy efficiency, providing simple, credible, and unbiased information that consumers and businesses rely on to make well-informed decisions. Thousands of industrial, commercial, utility, state, and local organizations—including more than 40 percent of the Fortune 500®—rely on their partnership with the U.S. Environmental Protection Agency (EPA) to deliver cost-saving energy efficiency solutions. Ninety-percent of American households recognize the ENERGY STAR, making it one of the most widely recognized consumer symbols in the nation.  Together, since 1992, ENERGY STAR and its partners have helped save American families and businesses more than  $450 billion and over 3.5 trillion kilowatt-hours of electricity while also achieving broad emissions reductions—all through voluntary action.

Know more about this https://www.energystar.gov/