Two giant low carbon greenhouses are to be built in the UK, to grow millions of tomatoes. According to estimates, their carbon footprint will be a quarter of that of regular greenhouses.
The greenhouses will be the UK’s largest - one-and-a-half times the size of the O2 in London. They will cover 29 hectares (72 acres) in total.
This will be big enough to grow 10% of the UK’s homegrown tomato crop, up to 20 tonnes of tomatoes a day.
The greenhouses are set to be built in Trowse, near Norwich, and Ingham, Suffolk.
The heat to create an ideal growing temperature will be pumped into the greenhouses from Anglian Water’s sewage treatment facilities. Backers of the plan say this system will be a world-first. The scheme will require the UK’s largest heat pumps, which will channel heat from warm water into the greenhouses to help speed growth, before returning cool water back to the river system. The carbon emissions from an on-site electricity plant will also be funnelled into the greenhouses for the plants to absorb.
This will cut carbon emissions associated with growing the crop by an estimated 75%.
Dr Lu Gilfoyle, head of environmental quality at Anglian Water, said: "It has been great to be involved in such an innovative project, helping to solve a number of challenges for Anglian. Removing excess heat from the river systems is a priority for Defra and ourselves, and it is fantastic to be able to put that heat energy to good use."
The 7-metre tall glass structures will allow crops to grow vertically along guide wires. They will be grown hydroponically, from nutrient-rich water solutions instead of using soil.
Britain consumes 500,000 tonnes of tomatoes a year but only 20% are home-grown.
Chris Starkie, chief executive of New Anglia LEP, said most tomatoes are currently imported from the Netherlands. He stated that "this is a huge opportunity for us to become more self-sufficient in tomatoes".
Costing £120m, the greenhouses will be funded by one of the UK’s largest clean energy funds - investment firm Greencoat Capital. James Samworth, a partner at the fund, said Greencoat saw “considerable opportunity” to invest in renewable heat in the UK. He stated that this could help generate stable returns while helping to reduce carbon emissions, as the UK works to become a carbon-neutral economy by 2050.
The concept for the greenhouse project was created by British developer, Oasthouse Ventures, to help reduce emissions from the agriculture sector, which is considered a “hard to treat” area of the UK’s carbon-cutting agenda. Andy Allen, Director at Oasthouse Ventures, said: “Delivering a world-first low carbon greenhouse system is hugely exciting for the small team who took this from conception, design and planning, to contracting and now construction. The environmental, social and political benefits of these systems are significant, and we look forward to further disrupting the traditional carbon-heavy models of agriculture.”
Greencoat estimates that the greenhouses could create 360 permanent agricultural jobs in the area, and up to 460 at peak season.
Work on the greenhouses has already begun, and crop growth is planned to start by autumn 2020.