Consumers have saved about $2 billion in energy costs over the last four years from more energy efficient set-top TV boxes because of a voluntary agreement between pay-TV service providers, manufacturers and environmental groups, according to a new report.

Energy consumption has been reduced by an estimated 16.8 TWh, and 11.8 million tonnes of CO2 emissions have been avoided over the same time period as a result of the agreement, energy consulting company D&R International said in the report, released Aug. 2.

First signed in 2012, the "Voluntary Agreement for Ongoing Improvement to the Energy Efficiency of Set-Top Boxes" was aimed at increasing the energy efficiency of set-top boxes while protecting rapid innovation and timely introduction of new features, the report said. The agreement was expanded in 2013 to include environmental groups like the Natural Resources Defense Council. One of the stipulations of the agreement is the publication of an annual report by an independent auditor.

In 2016, 98.6% of service providers’ set-top box purchases met Energy Star energy efficiency standards spelled out in the agreement, the report said. Under the agreement, the service provider signatories said 90% of the set-top boxes they purchased after December 31, 2013, would meet the Energy Star Version 3.0 standards.

"Based on the improved energy efficiency of the set-top boxes procured in 2016, it is estimated that the voluntary agreement reduced national set-top box annual energy consumption from 32 TWh in 2012 to 24.5 TWh in 2016, a reduction of 23.4%, even as energy-consuming functionality of set-top boxes has increased," the report said. "This 7.5 TWh reduction represents consumer savings of approximately $941 million and prevention of 5.2 million metric tons of CO2 emissions last year alone."

Additionally, close to two-thirds of set-top boxes in 2016 met stricter 2017 standards, the report noted.

The signatories also "substantially satisfied" other promises made in the agreement, but there is "room for continued improvement" in areas like improving consumer access to set-top box energy information on their web pages, the report said. "The signatories have fulfilled their commitments to deploy light sleep to pre-agreement set-top boxes, incorporate automatic power down in satellite set-top boxes, make whole-home systems available to subscribers, and provide reasonable access to energy efficiency information for set-top boxes purchased after January 1, 2014," according to the report.

The energy consumption figures were deemed accurate through independent field verification, the report concluded.

The agreement will expire at the end of 2017, but the signatories have indicated they could be willing to extend the agreement for several more years, according to the Internet & Television Association and the Consumer Technology Association.