The world’s first low-carbon greenhouses are being built in the UK with the capacity to meet over a tenth of the country's demand for tomatoes.
Two greenhouses, which are being constructed in Norwich and Bury St Edmunds, will be warmed using waste heat from a water treatment facility to reduce the carbon footprint of produce by up to 75%.
Greenhouses are designed to capture and store solar radiation to increase air temperature, but in Europe this method alone can't provide sufficient energy to reach optimal growing temperatures all year round.
Most commercial greenhouses use another source of energy such as a gas-fired boiler to heat the air to allow in-demand vegetables such as tomatoes to be grown year round.
Closed-loop heat pumps will be used to transfer the heat from Anglian Water recycling centres to the greenhouses, cooling the facility’s treated water outflow before it is returned to the environment.
Greencoat Capital, which has invested £120m in the project, said decarbonisation of the heating and agriculture sectors has been “disappointingly slow despite their enormous carbon output”, adding the greenhouses would be a significant step to dealing with the issue at scale.
The greenhouses are set to be the largest in the UK at 13 hectares each –three hectares larger than the O2 arena. They will also be 7m tall to allow for crops to be grown vertically across guidewires. The produce will be grown hydroponically from nutrient-rich water solutions.
Once in full production, Greencoat Capital said the facilities would have the capacity to produce 20 tonnes of tomatoes every day, approximately 12% of the amount produced by the UK.
James Samworth, partner at Greencoat Capital, said: “We’re very pleased to have achieved another innovative first in the UK renewable energy sector. Technology and cross-sector co-operation is continuing to unlock some amazing possibilities in energy and agriculture.
“We see considerable opportunity to invest in renewable heat in the UK, providing pensions investors with the predictable returns they require to pay beneficiaries, meanwhile reducing our carbon emissions as an economy.”
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