Sainsbury’s has opened what it claims is the UK’s greenest supermarket.

The timber-built store in Dartmouth, Devon, which opened this week, is heated by a biomass boiler that halves the amount of energy taken from the national grid. Rainwater is used to flush the toilets, reducing water usage by 60%.

The store has been built to avoid heat loss through draughts, while other power-saving methods include lower lighting levels and quiet wind turbines. “It is a leader in sustainable construction and is extremely low in energy use,” said Neil Sachdev commercial director for Sainsbury’s. “We now want to apply all these benefits to the rest of our stores.”

Stock will also be delivered using an environmentally friendly method as Sainsbury’s says it has become the first supermarket to fuel its lorries from bio-methane, which is produced from rotting waste. The retailer said this would cut carbon dioxide emissions by 60%.