Electricity bill
An electricity bill, in the context of buildings and their owners and/or occupants, is effectively an invoice detailing money that is owed for electrical energy that has been used.
In its simplest form, electrical energy will have been metered, usually in terms of the quantity of kilowatt hours that have a been used in a given time period.
A kilowatt hour or ‘Kwh’ is the quantity of energy that a load of 1Kw uses in 1 hour.
So:
1Kw running for 1 hour = 1Kwh
Equally:
0.5 Kw (500w) running for 2 hours = 1Kwh
And
2kW running for 30 minutes also = 1Kwh
1Kwh is also known as ‘1 unit of electricity’
The company supplying the energy will have set the price for the unit of electricity. This and other details that make up the bill will be detailed in the supplier’s terms and conditions. Such terms and conditions are known as tariffs.
Tariffs will vary widely between suppliers. As well as detailing the cost per unit of electricity, these will also cover other costs that make up the total amount owed.
In its most simple form, the bill will set out payment terms, such as payment due date, VAT rate if applicable and methods by which payment may be made.
On larger installations, it is common to see much more detailed tariffs, which may often encourage electricity saving at peak times and variable unit rates for different times of day.
With more complex tariffs, electricity usage will be charged while taking into account other factors such as:
- Time of day.
- Maximum demand at any given point in time.
- Seasonal variations.
- Power factor that electricity has been taken at.
- System usage charges.
- Payment methods.
The electricity bill must clearly set out all this information so that it is easy to establish how the total amount charged has been calculated.
NB Making Mission Possible - Delivering A Net-Zero Economy, published by the Energy Transitions Commission (ETC) in September 2020, suggests that the levelised cost of electricity (LCOE) is: ‘A measure of the average net present cost of electricity generation for a generating plant over its lifetime. The LCOE is calculated as the ratio between all the discounted costs over the lifetime of an electricity-generating plant divided by a discounted sum of the actual energy amounts delivered.’
--ECA
[edit] Related articles on Designing Buildings
- Articles about electricity.
- Consumer electronics.
- Consumer unit.
- ECA calls on Government to reform and rebalance energy levies and avoid cost of living crisis.
- Electrical appliance.
- Electrical consumption.
- Electrical energy.
- Electrical equipment.
- Electrical installation.
- Electrical power.
- Electrical safety.
- Energy cost.
- Energy price crisis: ECA calls for energy levy reform.
- Energy tariffs.
Featured articles and news
Plumbing and heating for sustainability in new properties
Technical Engineer runs through changes in regulations, innovations in materials, and product systems.
Awareness of the Carbon Border Adjustment Mechanism
What CBAM is and what to do about it.
The new towns and strategic environmental assessments
12 locations of the New Towns Taskforce reduced to 7 within the new towns draft programme and open consultation.
Buildings that changed the future of architecture. Book review.
The Sustainability Pathfinder© Handbook
Built environment agency launches free Pathfinder© tool to help businesses progress sustainability strategies.
Government outcome to the late payment consultation, ECA reacts.
IHBC 2025 Gus Astley Student Award winners
Work on the role of hewing in UK historic conservation a win for Jack Parker of Oxford Brookes University.
Future Homes Building Standards and plug-in solar
Parts F and L amendments, the availability of solar panels and industry responses.
How later living housing can help solve the housing crisis
Unlocking homes, unlocking lives.
Preparing safety case reports for HRBs under the BSA
A new practical guide to preparing structural inputs for safety cases and safety case reports published by IStructE.
Male construction workers and prostate cancer
CIOB and Prostate Cancer UK encourage awareness of prostate cancer risks, and what to do about it.
The changed R&D tax landscape for Architects
Specialist gives a recap on tax changes for Research and Development, via the ACA newsletter.
Structured product data as a competitive advantage
NBS explain why accessible product data that works across digital systems is key.
Welsh retrofit workforce assessment
Welsh Government report confirms Wales faces major electrical skills shortage, warns ECA.
A now architectural practice looks back at its concept project for a sustainable oceanic settlement 25 years on.
Copyright and Artificial Intelligence
Government report and back track on copyright opt out for AI training but no clear preferred alternative as yet.
Embedding AI tools into architectural education
Beyond the render: LMU share how student led research is shaping the future of visualisation workflows.
Why document control still fails UK construction projects
A Chartered Quantity Surveyor explains what needs to change and how.
Inspiration for a new 2026 wave of Irish construction professionals.
New planning reforms and Warm Homes Bill
Take centre stage at UK Construction Week London.


























