Lighting and energy use
This page explains how to manage your lighting system efficiently.
One of the first steps for churches and people to save energy and carbon emissions is to change the lightbulbs to low energy models. This page explains what needs to be considered in order to do this.
Also we should review our church’s heating system, and its settings; and we should switch to a green energy supplier. That’s if we haven’t done these things already – most of our churches have taken at least a couple of these actions. Others still need to take these steps.
See also Climate Action Plans, Generic Building Solutions and Climate Action Projects.
Typically lighting has consumed 10-15% of domestic energy, though that figure is reducing as low energy lighting is in wider use – while at the same time electricity use for gadgets is mushrooming.
Lighting still accounts for most of the electricity used in many churches. To function effectively, church buildings like any others obviously require artificial lighting.
There are several steps you can take to significantly reduce energy consumption and bills.
Replacing conventional light bulbs with low-energy models
By now we should all be replacing our old-fashioned incandescent light bulbs and spots with low energy light bulbs. These should now be mainly LEDs (light-emitting diodes) which are increasingly available. Fluorescent tubes or CFLs (compact fluorescents), may still be appropriate in just a few situations, such as cupboards and passages.
Tungsten light bulbs and opaque bulbs are progressively being banned. Tungsten filament light bulbs have been the reliable workhorse of lighting for many decades – but sadly they are wasteful and must be superseded.
CFLs were pushed too strongly before their shortcomings were understood. Really they are only suitable for domestic settings or minor ancillary parts of churches.
In a limited range of non-standard situations:
- Reduced energy lamps with about a 30% saving, usually halogen fittings, are also available;
- In some situations, flood lights can be replaced with CDMt floods – ceramic metal halides;
- Tungsten halogen display and security lights can be swapped for high pressure sodium or metal halide lamps to reduce energy use;
- Replace failing fluorescent lighting tubes with tri-phosphor coated models. These give more natural, brighter light and also save up to 30% on bills. If replacing fluorescent tube lighting, opt for the smallest diameter on lighting tubes as they use less energy.
Theatre lighting is a non-standard situation – the theatre industry is resisting the introduction of LEDs. A strong case needs to be made for a church to install high energy theatre lighting (and even to retain such a system that is already installed). LEDs are now the norm.
New lighting systems
When planning a new lighting system, remember to make it as environmentally friendly as possible – which basically means saving energy and carbon emissions to the highest extent possible.
As already stated, the wide range of LEDs now available are the staple for lighting in churches, although some combination of different types according to their position and purpose is still appropriate.
Advice given above for buying individual fittings or bulbs only still applies, except that you will not be constrained by re-using existing fittings or controls. Everything can be re-designed as new, to maximise benefits.
It is important to bear in mind the progressive dimming of some bulbs (‘lumen depreciation’). The colour may change too – so even if you keep spares from the same batch, they may not match if replacing any fitting that fails early. A different batch may well look different. A carefully considered replacement strategy, backed by sufficient guarantees from designers and manufacturers or suppliers, is strongly advised.
Modular fittings, requiring only part to be replaced not the whole unit, may also be advisable.
Careful consideration is needed to scene setting and controls – sophisticated but easy to use.
Low energy light bulbs cost more initially, but they consume less electricity because less is wasted as heat. Up to 80% of a church’s electricity bills can be saved this way!
Low energy bulbs also have a much longer life (eg 15,000 hours). The best LEDs can pay for themselves in 5 – 6 years – but in a church they could potentially last for 40 years!
A long lasting bulb is also useful for high or inaccessible light fittings. Consideration may be given to replacing all lamps together, whether or not all have failed, on a pre-arranged schedule. The saving in costs of scaffolding or cherry-pickers has not been included in the above assessment.
Sourcing and selection
The range of LEDs for every application has improved enormously. Low energy bulbs are now available readily available in the shops and come in various sizes and shapes designed to fit the standard bayonet and screw fittings.
Replacement lamps should be selected having regard to existing fittings. The new lamps need to fit in the old fittings! Like ‘new wine in old wineskins’!
It’s a good idea to inspect and test samples – the appearance of LEDs varies.
Careful and thorough comparison of types and suppliers pays dividends. The cheapest may not be the best. A well-known brand may not be either.
As a general rule, to choose a bulb for domestic use, take the wattage of the current old-fashioned bulb and divide by five. However it is best to err on the bright side – lights may get dimmer with age.
You can use dimmable low energy light bulbs, where they are required. Dimmable types are increasingly available. They need to be specifically labelled as such, and they need the right type of dimmer, otherwise the lamp may not work correctly and may be damaged.
For more information on how to choose the appropriate fitting and wattage visit Lightbulbs Direct.
Other suppliers from whom catalogues and/or quotations may be obtained include:
High street supermarkets also increasingly stock light bulbs, and there are specialist electrical retailers such as Ryness, where you can walk in and expect personal advice.
Always keep your receipts and be prepared to return a faulty bulb.
Good housekeeping can go a long way to save energy and costs. Here are some more tips:
- Do not leave lights on in an area of the building that’s not in use;
- Put up notices with a positive message like “Switch off here for one hour and save 25 litres of CO2!” (that’s just for a traditional 100W bulb! Increase or reduce in proportion to the rating x the number of fittings controlled by the switch);
- Consider installing timers and/or or passive infrared (movement) detectors (PIRs) in toilets; daylight and occupancy sensors (DOSs) in entrances; there should be a timed overrun for any fan in a toilet that’s controlled by the light switch;
- Regularly clean light bulbs and fittings – as well as windows and skylights – to allow as much light in as possible.
Floodlighting of church buildings has become popular. This can consume large amounts of energy, contribute to so-called ‘light pollution’ and be expensive to run.
The congregation needs to have a serious debate, involving the local community and the Council too, about the environmental impacts as well as any amenity benefits.
There may be more justification for the sake of security rather than just for visual enhancement – but best if they achieve both together.
Your local Council may be willing to contribute to installation and/or running costs.
If it is resolved to proceed with a floodlighting scheme, low energy light fittings should in most cases be used, including for example fibre optics, and an appropriate management system for the lighting.
If the reason for the scheme is visual enhancement, rather than floodlighting the exterior every evening, why not limit hours to say before 11 pm, or reserve use just for special occasions? The visual enhancement will be noticed more when it’s only on some of the time – as well as saving energy and costs, and reducing the contribution to climate change.
Replacing existing bulbs may not require permission, so long as their appearance is similar and there is no re-wiring involved, or permission may be obtainable by way of an archdeacon’s letter. This is known as the ‘List A’ or ‘List B’ process. Consult the Diocese’s Parish Property Support team.
New lighting requires a faculty. You will need to seek professional advice before seeking permission. See Generic Building Solutions and Making Changes and Faculties.
A Statement of Need is required as part of any proposal for faculty, justifying the scheme in terms of furthering the mission and ministry of the church.
External floodlighting may also require planning permission from your Local Authority.