Estimate the annual energy cost, carbon reduction and payback period of upgrading commercial lighting to efficient LED luminaires and controls. Start with a rough fitting count and the type of lighting being replaced; the detailed assumptions are optional.
The estimate is lighting-specific. It is not a whole-building EPC calculator, and it does not need a full schedule before it can give a first result.
Fitting quantity, wattage, operating hours and electricity rate usually decide the first energy case. A warehouse running old metal halide fittings for long shifts will usually show a stronger energy case than a lightly used office already fitted with modern LED panels.
Use the output as an early commercial lighting estimate before final product selection, controls, emergency provision and installation detail are confirmed.
The result compares current load against a proposed LED load, then applies the selected controls strategy as an indicative reduction. Switching, occupancy sensing, daylight dimming and DALI/Casambi zoning are kept separate because they have different wiring, driver and commissioning implications.
Lighting can be one of the electrical systems to review when a commercial building is being assessed for lower energy use, MEES planning or refurbishment, but EPC outcomes depend on the whole building.
Low-glare workplace lighting, LED panels, linear lighting, downlights, controls and emergency options.
High-output LED, robust luminaires, long operating hours, sensor control and emergency lighting.
Track, accent, downlight, display, back-of-house and emergency lighting layers.
Classroom panels, corridor lighting, estate-wide replacement, controls and emergency review.
Guest-facing lighting, corridor downlights, dimming, colour quality and emergency coordination.
DALI, Casambi, sensors, zoning and switching options aligned to control gear and commissioning.
Emergency luminaires, exit signage, self-test and monitored emergency options reviewed with the upgrade.
Manufacturer review of product range, output, optics, controls, emergency options and quotation information.
Lighting energy cost is estimated by multiplying the total lighting load in watts by annual operating hours, dividing by 1,000 to convert to kWh, then multiplying by the electricity cost per kWh.
Use your contract electricity rate if known. If not, use the default rate as an early estimate and update it when actual billing data is available.
Efficient lighting can contribute to lower building energy use, but lighting alone does not guarantee an EPC improvement. EPC outcomes depend on the whole building, including heating, cooling, fabric, controls and other services.
Yes. The calculator can include switching, occupancy sensing, daylight dimming, DALI/Casambi zoning or a combined controls strategy as an indicative reduction to proposed lighting use.
No. The result is an indicative early-stage estimate. Final pricing and product selection depend on layout, ceiling detail, mounting height, optics, emergency provision, controls and confirmed luminaire specification.
Yes. A schedule, room list, fitting count, photos or drawings can be used to produce a more useful manufacturer-led product direction.
Yes. Emergency lighting, exit signage, self-test or monitored emergency options should be reviewed with the main luminaire package rather than added separately at the end.
Assume 100 existing fittings at 72 W are replaced by 100 fittings at 36 W, each operating for 4,000 hours a year. Existing consumption is 28,800 kWh; the proposed load uses 14,400 kWh. At an illustrative £0.25/kWh, annual electricity cost falls from £7,200 to £3,600.
The £3,600 saving is energy only. These are example inputs, not a quotation, current tariff or verified equivalent-light replacement. Check delivered light output separately, and include controls, installation and maintenance only where their assumptions are known.
If you have an installed project cost, use the commercial LED payback calculator to compare that cost with the annual saving.