WHEN THE floor under the pews began to collapse with wet rot, the architect suggested it was time that Holy Trinity in Jersey — attached to the diocese of Winchester — thought about putting in oil-fired underfloor heating. It would cost about £20,000, largely paid for by the local ratepayers through the municipal parish system.

The old heating had been electric. “When you switched the heaters on the whole building hummed, and I could swear lights for miles around dimmed as we drew so much power,” says the Rector, the Revd Geoff Houghton. But the people of Holy Trinity opted for a “greener” system, rather than using either electricity or oil, and the parish committed itself to a geo-thermal heat pump which Mr Houghton describes as a “fridge in reverse”, drawing heat from underground.

These systems, he said, used to entail miles of pipework under a garden or field, which was not practical in a churchyard where there are graves. But a heat pump can now be installed using bore-holes, and at Holy Trinity they are having three bore-holes 300 feet deep, but only about eight inches wide (pictured).

“It means very simple trench work to a manifold outside the church, and, inside, the fixture is about the size of a fridge-freezer which, I’m told, will run silently.” The capital cost is £30,000 (paid for by the rates), the running costs will be “minimal”, and the congregation will be fund-raising only for the ancillary works — not too difficult on an island where “the church really matters to people, even if they don’t often go”.