Kent soft-fruit producer Clock House Farm announces £10m renewable energy project to grow berries out of season

Managing director of Clock House Farm, Oli Pascall

Managing director of Clock House Farm, Oli Pascall

Clock House Farm, a key member of the Berry Gardens co-op, has announced the rollout of a £10 million soft-fruit growing system designed to produce fruit outside the UK growing season while improving the company’s environmental footprint.

The initiative involves technology that will source the heat required for glasshouse production from the River Medway, which represents an untapped source of renewable heat in Kent.

The investment, said to be the biggest known river source heat pump system in the country – and the most significant investment in green energy for soft fruit in the UK – has taken three years to bring to fruition. It will deliver energy to a 6.5ha production site for raspberries (150 tonnes) and blackberries (300 tonnes), allowing the growing season for both fruits to be extended from the beginning of April until December.

The second half of the site is scheduled for completion by 2024, enabling a further 200 tonnes of strawberries to be added to the out-of-season offering.

The fruit is grown in high-tech poly greenhouses rather than standard tunnels and benefits from a consistent supply of heat from the Medway, which is more consistent than other heating methods.

The process involves extraction of river water (heated by the sun) which passes through a heat exchanger and is then discharged straight back into the river, having removed a couple of degrees of heat from the water.

A second loop then transfers this heat to the plant room’s six heat pumps to achieve a temperature of 45°C, after which it is then circulated out to the greenhouses.

The heat pump’s total output is 10.6 megawatts, which is equivalent to the same amount of energy produced by 106 automobile engines. To put this into context, one megawatt hour (the use of one megawatt or 1,000 kilowatts, for a whole hour) would power around 2,000 homes, according to Ofgem, the UK’s energy regulator.

To further benefit the environment, the farm has allocated a separate 8ha river meadow below the greenhouses to provide a large natural wilderness.

Commenting on the project, managing director Oli Pascall said: “Clock House Farm takes its responsibility as stewards of the natural landscape very seriously so sustainability and seeking out innovative, environmentally responsible initiatives within the business will always be top of the agenda.

“As growers, extending the season is imperative to our, and other British growers’, success by offering the potential for sales to be spread across a longer time frame and therefore ensuring less reliance on imported soft fruit.”

He added: “Of course, ultimately this also helps to reduce the carbon footprint. We will continue to seek out clean energy solutions and remain respectful of the fact that traditional energy supplies no longer represent an infinite resource.

“This is particularly apposite in light of the current situation regarding the conflict between Russia and Ukraine and the resulting impact of sanctions that have now been imposed.”