Private in-browser planning
Commercial Building Site Energy Intensity Tool
Starting values are hypothetical. Replace them with your own figures. Inputs stay in this browser and are not included in the energy inquiry.
- A complete year is required; partial data is not automatically annualized.
- Unadjusted site EUI only, without weather normalization or an ENERGY STAR score.
Use one complete year and the same building boundary
Collect a full twelve months of energy consumed by the property so both heating and cooling seasons are represented. Use all relevant meters and fuels for the selected property boundary. If a tenant meter or central plant allocation is missing, document the omission and avoid presenting a partial total as whole-building performance.
Use gross floor area corresponding to the included energy. Mixing a whole-building energy total with only leased or occupied area changes the interpretation. For a campus, shared plant or mixed-use property, establish the boundary before calculating. The denominator must be greater than zero, and a meaningful comparison requires the same area convention in each period.
How the site-energy calculation works
Electricity kWh is multiplied by 3.412 to obtain kBtu under the rounded EIA conversion. Natural gas therms are multiplied by one hundred because each therm is 100,000 Btu. Add other annual fuel energy already converted to kBtu. Divide the combined kBtu by square feet for annual site EUI, expressed as kBtu per square foot per year.
For an illustrative 50,000-square-foot property with 500,000 kWh and 20,000 therms, electricity contributes 1,706,000 kBtu and gas contributes 2,000,000 kBtu. Total included site energy is 3,706,000 kBtu, yielding 74.12 kBtu per square foot per year. These hypothetical figures demonstrate the calculation and are not a benchmark for a specific property type.
Site EUI, source EUI and cost are different measures
Site EUI describes energy consumed at the property using common energy units. Source EUI addresses upstream energy effects using a different methodology. An ENERGY STAR score has additional eligibility and comparison requirements. The output here should not be relabeled as source EUI or a score simply because it uses energy and floor area.
Cost intensity measures dollars per square foot rather than energy. A supplier price increase can raise cost with no change in site EUI, while a reduction in supply price can conceal higher consumption. Keep physical energy, cost and operating information together so a management report explains whether a change relates to price, use or the property boundary.
Interpret changes with operating context
Weather, occupancy, operating hours, process loads and building function influence energy use. A hospital and a lightly occupied warehouse cannot be fairly judged by an unqualified EUI ranking. Track the same building over time with consistent inputs, then use an appropriate benchmarking framework for broader comparisons. This tool intentionally supplies no generic good-or-bad threshold.
Retain meter records, fuel conversions, dates and gross area evidence. If the year contains unusual closures, construction or incomplete bills, explain that alongside the result. Use a recognized benchmarking process when weather normalization, source-energy accounting or an external performance claim is required. For spending analysis, calculate cost intensity separately rather than multiplying this output by an unrelated energy price.
Sources & scope
Primary references reviewed October 15, 2026. These sources support the stated concepts; actual tariffs, program rules and signed agreements govern the account. Decision examples and operational worksheets are original educational analysis.
- ENERGY STAR: What is Energy Use Intensity?
Annual energy divided by gross floor area; distinction between site and source EUI and different property types. - EIA: Energy units and calculators explained
Rounded energy conventions: 1 kWh = 3,412 Btu and 1 therm = 100,000 Btu. Natural gas heat content varies.