Research and analysis

Calculating the full cost of energy used by buildings

The Whole Life Cost of Energy (WLCoE) calculator helps building owners and operators to understand the full financial cost of the energy their buildings use.


Whole Life Cost of Energy calculator

This file may not be suitable for users of assistive technology. Request an accessible format.

If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email Please tell us what format you need. It will help us if you say what assistive technology you use.

Guidance on using the calculator


The full financial cost of energy used to heat, cool or power a building includes not only the cost of the fuel, but also the cost of operating, maintaining and replacing the plant that converts the fuel into usable energy. It is particularly difficult to calculate the costs of different types of energy, such as steam, space heating or electricity, generated from different types of on-site plant located across multiple plant rooms.

The Whole Life Cost of Energy (WLCoE) calculator is designed to help building owners and operators perform this calculation in a consistent and transparent way.

The calculator uses a levelised cost approach which enables comparison between different generation types with different capital and operational profiles. The power sector uses this approach widely to compare the unit costs of wind, solar, nuclear and other means of electricity generation on a consistent basis.

For building owners looking to connect to a local energy network, the whole life cost generated by the calculator can be a useful starting point to appraise any offers received for heat and / or cooling supply.

The calculator is issued in BETA form and we would welcome your feedback on it:

Published 24 January 2020