Report: Case Study Visit to Wakehurst Place

In the stunning grounds of Wakehurst Place, an Elizabethan Manor in Ardingly, West Sussex, is one of the most diverse places on earth. The Millennium Seed Bank holds specimens for over 13% of global plant species, most stored at -20°C in walk-freezers in a vault beneath the visitor centre and laboratories.

Led by Keith Manger and David Marchant MBE, the driving force of Wakehurst’s sustainability efforts, over 50 delegates from local businesses enjoyed a behind-the-scenes tour to find out how the site, managed by the Royal Botanical Gardens Kew, has drastically reduced energy and water usage and waste generation.

The event was arranged by the Sustainable Business Network as part of the University of Brighton’s Green Growth Platform, a business support programme that is helping develop a local, low-carbon economy in Sussex.

Keith stressed the importance of first monitoring resource consumption, to be able to pin-point areas for most effective cost savings.

37 incubators in the Seed Bank run 24/7, mimicking various conditions to stimulate seed germination. Working with the manufacturer, they were able to reduce hourly energy usage from 0.3 kWh to 0.07 kWh, saving 2,015 kWh electricity and £161 per incubator per year.

Likewise, energy efficiency was a priority in the design of the walk-in freezers. Using state-of-the-art compressors and controls, the four units use less than 1 kWh of electricity per hour. Keith explained that doubling originally suggested insulation levels as well as the large thermal mass of the glass jars the seeds are kept in also contributes to this.

On the roof of the seed bank sits a 50 kWp solar PV system, that provides around 46,000 kWh of renewable electricity each year, equivalent to 7.4% of their demand. Keith hopes that they will be able to enlarge to system, plus has plans to install a 500 kW wood chip boiler to replace dependence on eight oil fired boilers.

David, who was born at Wakehurst Place, led the tour of the grounds, including compost corner where lawn and plant cuttings and wood waste are turned into different grades of soil conditioner. Big Hannah, an in-vessel composter fed with food waste, has also allowed the on-site restaurant to reduce landfill waste collections by two 1,100 litre bins a week. The nutrient rich end product is used in the greenhouses to grow vegetables.

As delegates left site, after coffee and networking, a cherry picker was stretching to the top of a large conifer, putting up Wakehurst’s Christmas lights – LEDs of course!

Keith’s presentation can be downloaded here.

Green Growth Platform events continue with seminars exploring alternative methods to raise finance for environmental products and services and public sector tendering processes and technique in East Sussex and Christmas networking in Brighton. Events programme.