Wealthier parts of the world waste a lot of food, at huge environmental and social cost. One estimate holds that 40% of America's food supply is wasted. However, the second largest supermarket chain in the UK is salvaging something from the wreckage, 

Sainsbury's has abandoned the practice of sending food waste to landfill. Instead, their food waste will power selected stores. “It was the right thing to do, but also it was the right commercial thing to do," Paul Crewe, head of sustainability at Sainsbury's told Fast Company. "Putting food waste into landfill costs £150 per ton, and the alternative of [turning it into energy] is significantly cheaper. It's putting that waste to true, positive use." 

Organic material that can't be used by foodbanks or for animal feed is taken to biogas plants, where methane produced when it rots is burnt for electricity. Until recently that power was fed directly into the grid. The energy produced was equivalent to that used by three of Sainsbury's 1200 stores.

However, Sainsbury's happens to have a supermarket quite close to one of the power plants, so Crewe decided to run a line direct from station to store. The move doesn't change the overall environmental benefit of using the waste in this way, but it does provide a powerful symbol of what is possible, running the supermarket purely on the energy produced from waste. Crewe also sees benefits for Saisnbury's in being less reliant on the national grid. 

Solar panels placed on the roofs of its supermarkets are making an even larger contribution to reducing Sainsbury's emissions, making the chain the largest solar power generator in Europe as of 2012. Energy efficiency measures have cut consumption by 9% over four years, despite substantial growth in stores.

The efforts do not address the problem of wastage after food has been bought, which recently drew the attention of the House of Lords. Food waste has also been demonstrated to provide a potential source of biodegrable plastics. However, the most radical out of the box solution might come from the French chain Intermarché, who realized much of the waste came from fruits and vegetables people won't buy because of their looks. Through a combination of discounting and humor, Intermaché's “glorify the inglorious” campaign slashed the amount of waste food needing disposal.