Tesco opened a 52,000-square-foot store in January with a carbon footprint 70% smaller than a typical store built in 2006. The design of the new supermarket in Cheetham Hill, Manchester, will help Tesco meet its target to cut store emissions by 50% by 2020.
Almost one third of the reduced carbon footprint has been achieved through energy efficiency measures. A key contribution has been made by fitting clear glass doors on all refrigerated cabinets. Tesco had hesitated to introduce this common-sense approach earlier because of concerns over inconveniencing customers. Low-energy light-emitting diodes are used to light the fridges, further reducing their energy consumption.
Tesco has introduced more natural lighting into the store by fitting large skylights. Power for electrical lighting is linked to sensors that automatically adjust according to the level of daylight.
A further 20% of the carbon footprint reduction has been achieved by using carbon dioxide as a refrigerant gas instead of hydrofluorocarbons that typically have a global warming potential of 1,300 times greater than CO2. Last year, the UK’s top six supermarket companies including Tesco told suppliers that they wanted to phase out HFCs (ENDS Report 386, pp 20-21 ).
Much of the supermarket’s energy is supplied by a combined heat and power (CHP) plant with an electrical capacity of 200 kilowatts - one third of the store’s requirement - and a thermal capacity of 250kW - enough for all its needs.
The CHP plant will run on recycled vegetable oil instead of fossil fuels, reducing the store’s carbon footprint by a further 19%. The plant can also run on rapeseed oil, wood pulp oil or conventional diesel if necessary.
Two 2kW wind turbines on the roof provide a small amount of power. Rooftop wind-catchers use ambient air to ventilate the store, while the store entrance has a lobby to reduce heat loss.
Low-carbon materials were used to build the supermarket. These include a timber frame and wood cladding from sources certified as sustainable by the Programme for the Endorsement of Forest Certification. Signs are made from recycled cardboard rather than plastic and the packing areas at each checkout are made of plastic rather than metal.
Tesco would not reveal what the store cost to build, but said it was 10% more expensive than a conventional store. However, the improved design will almost halve the store’s energy bill.
Cheetham Hill is Tesco’s fifth model store, with each one being more efficient than the last. Tesco declined to say what the actual carbon footprint of the store is. Other supermarkets have built similar designs with Sainsbury’s store in Greenwich, south-east London, built in 2000, being one of the first.
Mark Sowter, Tesco’s head of environmental construction, said the new store was a milestone on the company’s journey towards cutting its carbon emissions. Tesco is committed to reducing carbon emissions from existing stores by 50% by 2020 compared with 2006. Although not all the features at Cheetham Hill may be applicable at other stores, Tesco is committed to at least halving the carbon footprint of all new stores.
Store energy consumption is responsible for 67% of Tesco’s carbon emissions. Investments in energy efficiency announced in 2006 (ENDS Report 376, p 4 ) helped reduce the company’s carbon intensity by 4.7% in 2007, according to its 2008 corporate responsibility report.
But improving energy efficiency may not be enough to reduce Tesco’s climate change impacts. The growth of Tesco’s operations - it operates more than 3,700 stores in the UK and abroad - led to an 8.6% rise in its total carbon emissions to 4.47 million tonnes in 2007. Tesco will publish its 2008 emissions data in May.