It’s November 2025, and I have been looking deeply into our options as a church to decarbonise our heating for a couple years. I thought I would share some of my learning from this time, learning gathered through talking with other churches, monitoring temperatures and understanding how this old building (Grade II* listed) behaves, exploring the various options and getting some guide estimates of cost. It has been very interesting and sometimes surprising.

Background

For those who are not already familiar with our story, All Saints is an old Anglican church built at the end of the Victorian period. It was the third church to be built on the site (the original Belltower is 14th Century), updated to be more able to meet the needs of the community.

It is a very busy church, in use five to seven days a week. There are a few offices with a large number of staff, youth and children’s work, a community meal and on another day a cafe, the usual music group and bell ringing practice, several prayer meetings and four services a week of varied styles. Alpha groups run during each term with the occasional Youth Alpha in addition. Being the ‘civic church’ for the parish, we also have the usual schools services on the usual festivals, as well as Veterans Day and Remembrance Sunday, and Christmas lights switch where we play a key hospitality role for the community. Of course, there are the usual weddings, funerals, and a good many baptisms in our baptistry pool as well as the old stone font.

The Tower end of the building holds a modern inner construction of two floors, with offices, meeting rooms, kitchen, toilets and lift, with a fairly efficient gas central heating system. The other two thirds of the church is the classic Nave and Chancel with Side Chapel and Vestry and Choir Vestry (now office) which is heated by a separate gas boiler and Victorian or Edwardian radiators (these were the focus of experiments with settings this year). Our total gas consumption is ~73,000 kWh, and electricity is ~25,000 kWh annually (before we installed solar panels a year ago – but that’s another story).

Monitoring temperatures

Just in the interest of understand how the building responds to heating, and to keep tabs on whether or not it is warm enough, I’ve placed several thermometers at different points in the church, including one on the Pulpit (to hopefully be representative of the Nave temperature) and one in the apex of the Nave by the

Talking to other churches

A low carbon heating symposium

Early guide estimates

Our real-life heating experiment

Resources

A great resource for our learning has been the Facebook group Heat Pumps UK and Ireland. It has been a helpful source of information and discussions, but we’re always aware that a confident or strongly expressed opinion doesn’t mean they’re right. Another helpful resource has been the Heat Geek channel on YouTube, which explains a lot of the technical decisions in consumer-friendly language, and does experiments exploring different aspects of installation and controlling. There have also been a few accounts of personal heat pump experiences such as from the Electric Vehicle Man channel, or Tom Bray.

References