The calculator multiplies heated area by annual energy use per area unit. This produces a transparent annual demand in kWh. Include only spaces inside the same heated envelope and make sure area and intensity use the same measurement basis.
How to use the calculator
Select metric or imperial area units and your currency.
Enter the area that is actually heated.
Enter measured or professionally derived annual energy use per m² or ft².
Enter the energy-only price per kWh and calculate annual demand, annual cost, and monthly cost average.
Worked example
A heated area of 120 m² at 100 kWh/m² per year gives 12,000 kWh of annual demand. At 0.25 currency units per kWh, annual cost is 3,000 currency units and the calculated monthly average is 250.
Limits of the simplified estimate
Weather, building standard, indoor temperature, ventilation, and system efficiency affect consumption. Standing charges, maintenance, billing adjustments, and seasonal monthly variation are not included automatically. The result is not a utility bill or heat-load calculation.
Frequently Asked Questions
Which area should I enter?
Use the area actually heated inside the building envelope being assessed. Exclude unheated basements, garages, and outside areas unless the intensity figure includes them too.
How can I find a suitable energy intensity?
Prefer measured annual use divided by heated area or a professionally derived planning assumption. The calculator inserts no regional default.
Which unit should the energy price use?
Enter the variable price per kWh directly in the selected currency. The currency selector changes the unit only and performs no exchange-rate conversion.
Are standing charges and maintenance included?
No. Add standing charges, maintenance, repairs, and other fixed costs separately when comparing full costs.
How can I compare two consumption scenarios?
Keep area, units, and energy price unchanged and alter only energy intensity. This isolates the calculated effect of a different consumption level.
Why is the result not a heating bill?
The estimate uses only your annual assumptions. Weather sequence, billing period, standing charges, meter adjustments, and seasonal monthly distribution are excluded.
