Start with a walk-round
Pick a time when the building should be empty, such as early morning, a weekend or after close, and walk round. Note everything that's on: lights, heating, air conditioning, extraction fans, compressors, vending machines, monitors, hand dryers. Out-of-hours consumption is often a surprisingly large share of the bill and is pure waste. If you have a smart or half-hourly meter, your supplier or a free online tool can chart the overnight "baseload" for you.
Free
Correct heating and cooling schedules; switch-off routines; raise cooling and lower heating setpoints by a degree or two; turn off idle equipment; stop heating empty rooms.
Low cost
LED lighting; occupancy and daylight sensors; timers on water heaters and vending; pipe lagging; draught-proofing; door closers; fixing compressed air leaks.
Moderate
Building management system upgrades; variable speed drives on fans and pumps; heat recovery; efficient motors and refrigeration.
The Energy Saving Trust also publishes independent advice for organisations.
Lighting
LED lighting typically uses a fraction of the energy of older fluorescent or halogen fittings and lasts much longer, which also cuts maintenance. In warehouses and car parks, pairing LEDs with presence detection can cut lighting energy much further because areas are often empty. Replacing old high-bay lamps is one of the most reliable paybacks available.
Heating, ventilation and cooling controls
- Check that time clocks match actual occupancy, including after the clocks change.
- Set a "dead band" between heating and cooling so they never run at the same time.
- Reduce ventilation rates when spaces are lightly occupied, while keeping air quality healthy (CO2 sensors help).
- Lock or limit thermostats that are constantly adjusted.
- Service equipment: dirty filters and coils waste energy.
Compressed air
Compressed air is one of the most expensive forms of energy on a factory floor, and leaks are common. Listen for leaks when the site is quiet, tag and fix them, reduce the system pressure to the minimum that tools need, switch compressors off out of hours, and recover compressor heat for space or water heating.
Refrigeration and kitchens
Keep condensers clean and well ventilated, fit night blinds or doors on open chillers, check door seals, defrost regularly and avoid setting temperatures colder than necessary. In kitchens, switch equipment on when needed rather than all at the start of the day.
IT and office equipment
Enable power management on PCs and monitors, switch off at night, consolidate printers, and consider whether on-premises servers could be virtualised or moved to efficient hosting. Server rooms are often cooled far more than modern equipment requires.
People and process
Behaviour change works best when it's easy and visible. Name an energy champion, share simple monthly figures, and put switch-off responsibilities into closing checklists. Recognise improvements. A few percent saved through habits costs nothing and persists if it's built into routines.
Measure, then keep measuring
Sub-metering big loads, or even just reading the main meter weekly, lets you spot drift and prove savings. Without measurement, gains tend to fade as settings creep back.
Larger organisations in the UK may already fall under the Energy Savings Opportunity Scheme (ESOS), which requires periodic energy audits. Even if you don't, an ESOS-style audit is a good template. See funding & schemes.