Measure annual energy per area for any building. Switch units, track sources and verify totals. Turn inputs into clear EUI results for planning fast.
| Building | Area (ft²) | Electricity (kWh/yr) | Gas (therms/yr) | Mode | EUI (kBtu/ft²·yr) |
|---|---|---|---|---|---|
| Office, mid-rise | 25,000 | 180,000 | 1,200 | Gross | ~38.6 |
| Warehouse | 60,000 | 90,000 | 400 | Gross | ~9.1 |
| School with solar | 45,000 | 220,000 | 1,600 | Net | Varies by solar output |
Energy use intensity summarizes annual site energy per floor area, enabling fast comparison between concepts, buildings, and retrofit options. When used early, it highlights oversized loads, poor envelope assumptions, and schedule-driven consumption before drawings are fixed. For project teams, EUI becomes a target that guides specs, procurement, and commissioning scope.
The calculator accepts electricity and multiple fuel streams, converting them into a common unit for consistent totals. Use utility bills, submeter records, and commissioning logs when possible. If your data covers less than twelve months, set the period months so annualization reflects the actual measurement window. Note meter dates, gaps, and deliveries so each conversion can be traced later. If you only have estimates, enter them but flag the assumption in your notes and exports clearly today.
Gross EUI represents the building’s demand without crediting onsite generation. Net EUI subtracts onsite renewable output and is helpful for communicating post-solar performance to stakeholders. For compliance or benchmarking, confirm whether the program expects gross or net and report both when required. Report the selected mode and renewable assumptions to avoid confusion during reviews.
Once you calculate EUI, store the value alongside climate zone, operating hours, occupancy, and major system types. Track EUI at milestones such as schematic design, design development, and post-occupancy. A stable reduction trend usually comes from envelope improvements, efficient HVAC selections, and controls that reduce after-hours loads. Use the breakdown table to prioritize high-share sources. Pair EUI with peak demand and comfort checks to keep efficiency aligned with performance.
Construction energy can distort early readings, especially when temporary heaters, dehumidifiers, and drying equipment run continuously. Separate temporary power and temporary fuel where you can, and document major events like concrete curing or extended commissioning. Clear records improve year-over-year comparability and make the exported reports easier to audit. Recalculate after the first full operating year to set a reliable baseline.
It depends on building type, climate, and operating hours. Use local benchmarks, past projects, or portfolio averages. Compare like-for-like and focus on improvement trends rather than a single number.
Yes, when the period is representative. Enter the months measured so the calculator scales totals to a twelve-month basis. Avoid annualizing during unusual shutdowns, major tenant changes, or temporary construction loads.
Negative values occur only in net mode when renewable generation is credited. The credit subtracts from the total site energy, reducing the final EUI. Switch to gross mode to view demand without credits.
Yes. Each input is converted to a common site-energy basis before totals are calculated. Choose the unit that matches your bills. Consistency matters most for benchmarking across projects.
No. It reports site-based EUI using standard heating values and unit conversions. If you need source EUI, apply location-based or market-based source factors externally and document the factors used.
Use one consistent floor area basis across all comparisons, such as gross floor area or conditioned area. Document the definition and keep it aligned with your benchmarking program to avoid misleading results.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.