How the facility electricity intensity calculator works
Annual electricity intensity = annual facility electricity in kWh ÷ gross floor area in m². Gross floor area must be positive. The result covers electricity only; other fuels must not be silently omitted from a claim about whole-building energy use.
Electricity at your reference = gross floor area × entered reference kWh/m²/year. The signed difference is actual electricity minus reference electricity. A positive difference means actual electricity is higher than that entered reference; a negative difference means lower.
Actual and reference energy charges each extend their unrounded electricity quantity at the same entered flat energy rate and round half-up to cents. The displayed charge difference subtracts those rounded charges. Fixed account charges, demand charges, tariff tiers and taxes are excluded.
This is not whole-building site or source EUI, an ENERGY STAR score, or a normalized performance ranking. Use compatible building areas, annual periods and meter boundaries. Activity, occupancy, weather and fuel mix can explain differences. ENERGY STAR’s EUI guidance defines the area-based concept and distinguishes the more comprehensive metrics.
Worked example
120,000 kWh over 1,000 m² is 120 kWh/m²/year. A reference of 100 kWh/m²/year corresponds to 100,000 kWh, leaving a signed difference of 20,000 kWh. At an illustrative 0.18/kWh, actual energy charge is 21,600 and the reference charge difference is 3,600. Changing annual electricity to 100,000 makes intensity 100 and both differences zero.
Sources and assumptions
The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.
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