Two billion seeds stored at Kew's Millenium Seed Bank in West Sussex are to be kept cool by solar panels.
A total of 270 panels have been installed on the roof of the facility at Wakehurst Place in Ardingly, near Haywards Heath.
Tomorrow, the longest day of the year, they are expected to produce up to 400 kWh of electricity.
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Archive documentary from 1980 on the 80th anniversary of Beaulieu. Lord Montagu talks about the museum's royal connections