Bills, meters and consumption
kW, kWh and kVA explained for business energy
What is the difference between kW, kWh and kVA?
kW describes a rate of power, kWh describes energy used or generated over time, and kVA is a measure used in electrical capacity and connection planning. They answer different questions: how hard equipment is working, how much energy was used, and what apparent capacity may be required.
Written by Energy Guide editorial team · Specialist review: Pending · Source checked:
Power is not the same as energy
A 100 kW load operating for one hour would use 100 kWh. The same load operating for ten hours would use 1,000 kWh. This distinction matters when comparing equipment ratings, annual consumption and solar generation forecasts.
Capacity can create a separate question
Larger sites may have an agreed or available capacity expressed in kVA and related charges or constraints. The appropriate level depends on the connection, peak demand, power factor and planned equipment; it should not be changed from a bill alone.
- Ask whether a figure is measured, contracted or modelled
- Check the period behind every peak-demand figure
- Separate annual kWh from maximum kW
- Confirm agreed capacity with the relevant records
- Include planned EV, heating, solar or battery changes
Use qualified technical input where needed
A bill review can identify a question, but connection capacity, protection and equipment design are technical matters. Confirm material changes with the network operator and appropriately qualified advisers.
Sources
These sources support the explanation above. Check the linked source for current rules and eligibility.