Generating your own energy
This page offers an overview and introduction to options for renewable electricity or heat in churches and other buildings.
Renewable energy forms part of the Diocese’s campaign to reduce its contribution to climate change. See also Generic Building Solutions.
The Church of England and the Diocese of London are striving to meet our long-term target to reduce energy use and carbon dioxide (CO2) emissions (which cause climate change). This target is a reduction of 80% by 2050, compared to 2005.
To meet this target, a major increase in the generation of energy from renewable sources is a necessity. This helps reduce net energy use and thereby CO2 emissions.
So what is renewable energy?
Taken literally, ‘renewable energy’ should eliminate net energy consumption to zero. That is to say, every unit of energy used should be replenished in full from natural sources.
This contrasts with the use of fossil fuels like oil, coal and gas, which are dug out of the earth and not replaced. Using fossil fuels depletes our fundamental mineral resources, and it also causes climate change. Using fully renewable energy would not deplete our natural resources, and it would also not add to climate change. This is because the process of renewal naturally absorbs the greenhouse gases which cause global warming.
We lack any technologies which are 100% renewable. Solar panels and biomass heat come closest to this aim. Both do require some energy to be expended and emissions generated in course of manufacture and deployment. But they can repay that energy within a few years.
Low and zero carbon technologies (LZCTs)
Other technologies also often described as ‘renewable’, eg heat pumps, may expend some electricity in raising the heat. But their overall carbon footprint is still much less than it would take to generate the same units of energy from fossil fuels. Therefore we can also speak of ‘low and zero carbon technologies’ or LZCTs.
It may be possible to set up some of these technologies on a ‘micro scale’ on your church site or other premises.
The benefits of renewable energy are, in general:
- It is clean and occurs naturally
- It is almost infinite
- It produces less waste products and pollutants
- It causes less damage to the environment
- It produces less greenhouse gases which cause global warming.
Installing renewable energy technology can:
- Enable you to make a big contribution to helping the environment
- Be a rewarding project
- Turn ‘waste’ into a resource
- Attract visitors
- Serve as an educational tool
- Make a statement to the outside world that your church, and more broadly the Church of England, is taking the care of the environment seriously
- Save money, in the long term; installation costs remain high for some technologies, but are coming down considerably for solar PV, for example.
Significant progress in installing renewable energy has been achieved by the Church of England. This includes a growing range of examples in the Diocese of London. See Climate Action Projects.
An interesting comparison between progress on renewable energy in different countries is to be found on the BBC at EU leaders face pressure to deliver on climate change. The UK is lagging behind; the Church can help it catch up!
It is always best to begin with the most cost effective and simple ways of reducing carbon emissions, such as switching to low-energy lighting, optimising your heating and recycling waste. See Heating and energy use and Lighting and energy use.
Once these more simple changes have been acted upon you may, using the involvement of professionals, wish to look more seriously at the feasibility of generating your own electricity or heat.
Types of renewable/low and zero carbon technologies
Technologies which might be considered include:
- Solar panels (PV (photovoltaic) cells and solar hot water
- Ground source and air source heat pumps
- Biomass heating
- Combined heat and power (CHP)
- Wind turbines
- Anaerobic digestion (so-called biogas).
Solar panels are used to generate energy using heat and light from the sun. This is the most viable method currently available to many churches.
Biomass heat, ground or air source heat pumps are also worth considering.
These technologies are considered in more detail on other pages – see links below.
In some cases combined heat and power generation may prove to be useful and viable.
Wind power on a church is not considered viable in London, or on most UK churches. Also it can alienate local communities. Anaerobic digestion also is unlikely to be feasible or viable for churches.
Solar power is one of our best sources of sustainable energy, already the most tried and tested renewable technology with application to churches.
Churches have commonly been designed in the past so that half of the roof faces in a southerly direction, making them ideal recipients of sunlight and potentially beneficiaries of solar energy.
There are two keys uses for solar power: to generate electricity through Solar PV (photovoltaic); or to use the sun’s radiation to heat water.
See Solar panels.
A biomass boiler may be used to heat both space and water in your church or home.
However, in spite of the wood-burning fire or stove having been around almost as long as our species itself, the modern biomass boiler is a less well-trodden path than solar PV, and there are issues to pay close attention to.
See Biomass heating.
Ground and air source heat pumps
Heat pumps have been employed successfully on several sites in the Diocese, most notably the parsonage of St John Wembley.
They can work very well at domestic scale, and may also be suitable for some church halls.
The principle is a simple one – a heat pump works as a refrigerator in reverse. It cools the ground or the air while warming the inside of the building. The heat thus extracted is low grade, therefore it needs to be well deployed usually at low level, and in a well-insulated space.
See Heat pumps.
Combined heat and power (CHP)
CHP employs an on-site generator to produce electricity. This generates heat as a by-product, which is recovered to contribute to heating the building(s).
CHP works best when serving a group of buildings which require heat at different times.
If considering this, seek the advice of the Head of Environment and Sustainability.
Renewable energy projects may be financed through a mix of parish giving, government subsidies, and/or grants or loans.
See Climate Action Finance.
Some of these technologies will involve a significant alteration to the visual appearance and/or fabric of a building.
A faculty will normally be required for your church building. Planning permission from your Local Planning Authority (Council) is also likely to be required, if there is a material change in external appearance, and/or if the building is listed or in a conservation area.
There is no automatic bar to making changes which affect a church’s appearance – but it must be done well. You are likely to need to make every effort to mitigate the visual impact of any new installation, in order to gain permission.
Therefore you should consult the local authority and the DAC as soon as possible.
Consultants and engineers
Professional advice should be sought.
It is important to retain the services of consultants and installers who are technically proficient, and also well versed and practised in relation to renewables and any subsidies applying.
In addition to an experienced engineer, you may need an architect to coordinate your micro-generation project – he or she could be your Quinquennial Inspector.
Installers and systems should be certified under the Microgeneration Certification Scheme (MCS).
See Resources on the environment.
More information and advice
Advice can also be sought from the Parish Property Support Team and the Head of Environment and Sustainability.