Solar panels have provided Gloucester Cathedral with enough electricity to make 250,000 cups of teas and reduced energy bills by a quarter.
Blessed in the pouring rain by the landmark's dean a year ago, bosses say the 150 devices have performed better than expected.
Explaining how the panels have proven popular with environmentalists and conservationists alike, project manager Anne Cranston told Premier: "It's been nothing but positive; it's brought a whole new audience to us.
"We're learning; we're taking our role as custodians seriously, and we are very much caring for the environment and God's creation."
The solar panels have generated 31.12MWh of energy during the past twelve months - enough to power seven semi-detached houses - and saved the landmark £4,000 in electricity costs.
They have also prevented 12,199.91kg of carbon dioxide emissions, the equivalent of planting more than 40 trees.
Anne Cranston added: "One of the things that we've learned from the conversations that people have had with us since we installed the panels is there is an awful lot more that we can do and quite a lot of it is relatively simple."
Click here to listen to Anne Cranston speaking with Premier's Alex Williams: