A specification showing a number in kW does not, by itself, let you calculate a capsule home’s electricity bill. To assess running costs, you need to know what that figure represents and how much energy will be used over a defined period.
Two units, two questions
IDAE identifies kW as a unit of power and kWh as a unit of energy. Power expresses a rate of energy use; consumption over a period is expressed as energy. A power figure is not automatically a daily consumption figure.
| Item | Useful question |
|---|---|
| Electrical power, kW | Which appliance or group, under which operating condition? |
| Energy, kWh | Over what duration, occupancy and conditions? |
| Cost, euros | Which tariff, charges and period are included? |
An explanatory example, not a forecast
A hypothetical appliance maintaining electrical power of 1 kW for 2 hours uses 2 kWh. Running at the same power for 30 minutes would use 0.5 kWh. This is illustrative arithmetic: it does not represent a commercial model or the actual behaviour of an air conditioner, whose operation can vary.
Organise consumption by activities
List the equipment in the configuration you are considering: heating and cooling, hot water, cooking, lighting and other appliances. This is a practical way to organise questions, not an invitation to add all catalogue power ratings and treat the total as constant consumption. IDAE also distinguishes residential energy uses.
Ask the supplier whether its figure concerns installed power, one appliance, a forecast or a measurement. If an annual estimate is provided, request assumptions about climate, indoor temperatures, occupancy and equipment. For a real example, establish what was measured and on which dates.
Deciding without promising a bill
A useful comparison holds operating conditions constant. Two capsules having the same floor area or similarly labelled equipment is not enough. Retain the explanation for every figure with the quotation version. Ask the project professional to review suitable installation and supply; this guide does not size electrical protection, service connections or contracted power.
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Sources and scope
IDAE: kW and kWh definitions and residential-use definitions, read on 17/10/2026. Example and checklist by CasasCápsula. Unsponsored; no consumption figures attributed to products.