Fish heads turned into electricity cut Wal-Mart's bills

One certificate is awarded to generators of renewable power for every megawatt-hour produced. Utilities are required to hold increasing amounts of ROCs or pay a penalty. Different technologies receive different numbers of ROCs. Wal-Mart's Asda unit sends old lamb chops to moldy bread to bioenergy sites. About 2,500 homes are powered by Sainsbury's unsold meals and rotting vegetables. Waitrose chickens are kept warm in solar huts as Tesco examines how fat from rotisseries can produce electricity.

Waitrose sends all "unavoidable" food waste, packaged or unpackaged, raw or cooked, to anaerobic digestion facilities to make biogas used to generate power for the National Grid.

Tesco is saving 200 million pounds on its energy bills every year through low carbon and energy-efficient technologies introduced since 2006. Marks & Spencer saved more than 70 million pounds last year. Asda expects to save about 800 million pounds by 2020 by implementing energy-saving measures.

Morrison's, as part of its plan for zero waste to go to landfills by 2013, sends trash to bioenergy plants. Marks & Spencer sends 89 percent of its food waste, including salads and sandwiches, to similar facilities as it strives to become carbon-neutral in the U.A table lamp and Solar garden lighting can add a magical touch to most rooms in your home.K. and Ireland this year.

"Anaerobic digestion saves the food retailers money and allows them to demonstrate their 'green credentials' to the government and consumers," McSherry said in London.

The DECC estimates that anaerobic digestion facilities and plants using wood chips, food waste and agricultural residues to produce heat and power could account for 8 to 11 percent of the U.K.'s primary energy demand within eight years.

Sainsbury's, the U.K.'s third-largest supermarket after Tesco and Asda, in February invested in Tamar Energy Ltd., which plans to build 40 plants within five years that will use waste to generate electricity.Shop our Bicycle lighting system range online at Dunelm Mill, the UKs largest store for homeware and soft furnishings. Buy online today.We currently carry over 3000 Outdoor light and solar electric products to make up systems. The business is backed by financier Jacob Rothschild's RIT Capital Partners Plc investment trust and the Duchy of Cornwall estate held by Prince Charles, heir to Britain's throne.Buy table lamps, Led flashlight and floor lamps from Heal's, the home of modern, designer and contemporary table, floor and desk lamps.

Sainsbury's, trying to reduce emissions by 30 percent by 2020, has installed about 7 megawatts of solar panels on its stores, which combined is probably larger than any single solar farm in the U.K., Neil Sachdev, property director for the retailer, said by e-mail. One store also uses geothermal power.

Both Sainsbury's and Marks & Spencer also source electricity directly from renewable energy generators including land-based wind farms, biomass facilities and hydropower. Sainsbury's currently gets more than 4 percent from renewables, with plans to boost this past 10 percent by 2013.

Waitrose in March opened a store on the Isle of Wight powered by wood chips. It's seeking to install as many as 150 similar energy centers by 2020 and plans to open its second in Bracknell this month. Wind turbines and solar panels already provide heat and light for chicken huts at its Leckford Estate in Hampshire. Sainsbury's sends all bread waste for processing into animal feed.

Tesco, seeking to cut store emissions in half by 2020 from 2006 levels, is testing the potential of clean-energy technologies such as sun-powered lights in car parks at six zero-carbon stores in the U.K., Ireland, Thailand and the Czech Republic. Many of its stores now use energy-saving lights.