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Office Building Energy Efficiency

You’re paying to heat, cool and light space that isn’t always occupied. Smaller offices can trim waste mainly through schedules, thermostats and habits—before spending on big plant upgrades.

Next step: If you use under about 50,000 kWh a year, you can get a quote in under 90 secs online — fast, no obligation. Bigger supply, half-hourly metering, or prefer chat? Use the contact page.

Where Office Energy Goes

Every office differs; the split below is a rough picture to show where to look first—then dig into heating and cooling, lighting and out-of-hours use.

• 45% HVAC - Heating, cooling, ventilation
• 25% Lighting - Desk lights, ceiling lights, meeting rooms
• 15% IT equipment - Computers, monitors, servers, printers
• 10% Small power - Kettles, microwaves, phone chargers
• 5% Other - Security, lifts, water heating

Real Example: 200m² Office (10 Staff)

Typical consumption: 120 kWh/m²/year

200m² × 120 kWh = 24,000 kWh/year × 26p = £6,240/year

Breakdown: £2,808 HVAC, £1,560 lighting, £936 IT, £624 small power, £312 other

HVAC: Biggest Cost, Biggest Savings

The 1°C rule: Every 1°C reduction in heating saves 8% on heating costs.

Reduce from 21°C to 19°C = 16% saving = £449/year (zero cost!)

Out-of-hours setback:

• Problem: Many offices heat/cool 24/7
• Solution: Programmable thermostat (£200-400)
• Set heating to 12°C overnight and weekends
• Pre-heat 1 hour before staff arrive
• Saves: 20-30% HVAC = £562-842/year

Lighting: Quick LED Wins

Replace 40× fluorescent tubes with LED equivalents:

• Old: 40 × 58W × 10h/day × 250 days = 5,800 kWh/year = £1,508/year
• New: 40 × 18W × 10h/day × 250 days = 1,800 kWh/year = £468/year
• Saving: £1,040/year
• Cost: 40 tubes @ £12 = £480
• Payback: 5.5 months

Occupancy sensors for meeting rooms: Auto-off when empty. Cost £80-150 per room, saves 30% lighting in those areas.

IT Equipment: Set It and Forget It

Computer sleep mode: Configure all PCs to sleep after 15 mins idle. Saves 50% IT energy = £468/year (zero cost).

Turn off monitors: Monitors use 30% of PC power. Train staff to switch off at end of day = £140/year saving.

Unplug phone chargers: Chargers left plugged in waste £50-80/year across 10 staff.

Staff Behavior (Zero Cost)

• Last person out switches off lights in communal areas
• Close blinds in summer to reduce cooling load
• Report draughts/poor insulation immediately
• Use natural daylight where possible (turn off desk lights)
• Don't prop open fire doors (wastes heating)

Related Guides

Your next step: When you are ready to compare business tariffs, get a business energy quote online (typically under a minute, no obligation). Larger supply, half-hourly metering, or you prefer messaging? See the contact page.