Maidenhead Synagogue has installed solar panels on its roof - the first shul in the country to do so, it claims.
"The main motive was fulfilling Jewish teachings about preserving the environment and a desire to play a part in the fight for sustainability," minister Rabbi Jonathan Romain said. "The panels also serve as a powerful message to congregants about Jewish eco-values.
"If it leads to all 800 of our households installing their own solar panels, it will have a massive knock-on effect."
A combination of grants, donations and fuel bill savings are recouping the £20,000 cost. The synagogue not only generates its own electricity but sells its excess to the national grid, earning £1,500 annually. Former Maidenhead chair Danny Allen and energy specialist Ellen Salazar led the project.
The shul's self-sufficiency extends to a vegetable garden, growing tomatoes, cucumbers, potatoes, lettuce, carrots and onions.
Fuel bill savings will help to recoup the £20k cost
Produce is used both at the Shabbat kiddush and for the weekly lunches for the homeless the synagogues organises.
There is also a wormery for decomposting wastage.