About UKGRIDWATCH
UKGRIDWATCH is an independent, personally maintained project that helps readers explore how Great Britain’s electricity system changes through the day. It brings public energy data into a readable dashboard and historical charts, with explanations for people who do not work in the electricity industry.
What the figures describe
Despite the UKGRIDWATCH name, the main grid views concern Great Britain: England, Scotland and Wales. Northern Ireland operates within a separate all-island electricity market. A Great Britain figure should therefore not automatically be described as a total for the whole United Kingdom.
Demand describes the rate at which electricity is required within the scope of the reporting dataset. Generation describes the output of power sources such as wind, gas, nuclear and solar. Imports, exports, storage, network losses and differences in data coverage mean that a selection of generation figures will not necessarily add up to the displayed demand.
A practical way to explore the grid
Start with the live dashboard for a snapshot, then open historical data to see whether the latest reading is typical of the available period. Comparing wind and gas output can reveal how the generation mix changes. Looking at demand alongside those changes adds context: a different mix can reflect changing consumption as well as changing supply.
Power and energy measure different things. A gigawatt (GW) is a rate of output or use; a gigawatt-hour (GWh) is an amount of energy. An output of 1 GW sustained for one hour produces 1 GWh. A peak on a power chart does not, by itself, tell you how much energy was supplied over a day.
Carbon intensity expresses carbon dioxide emissions per unit of electricity, usually in grams of CO₂ per kilowatt-hour. It is different from total emissions: total emissions depend on both the intensity and the amount of electricity involved. A national average also does not identify the exact source of electricity reaching an individual home.
Data, sources and limitations
The site presents public energy data through its own collection and display code. The history page reads locally stored observations and a compact longer-term archive. Its Market Index Price view requests Elexon data for the shorter ranges and uses the local archive for the 12-month view. Coverage depends on the observations available; selecting a longer range does not create missing historical records.
Different feeds can report at different intervals, use different definitions or be revised after publication. Collection interruptions and delayed updates can affect what appears on a chart. Treat the figures as an aid to understanding patterns, and check the original publisher’s definitions and latest records before drawing a detailed conclusion.
For further reading, the NESO historic generation mix dataset explains generation and carbon-intensity reporting. Elexon’s Market Index Definition Statement overview explains the purpose of the wholesale price index. These are reference resources; their datasets may differ from the specific observations stored on this site.
How the project is supported
UKGRIDWATCH is maintained in spare time. Advertising may appear on the site, and readers can also choose to contribute through the support page. Advertising and voluntary support can help cover hosting, maintenance and development. The presence of an advertisement does not imply an endorsement of the advertiser or its products.
Purpose and independence
The aim is to help students, teachers, journalists and curious readers ask better questions about electricity: what changes, when it changes and what the data can actually tell us. Explanations are intended to distinguish observations from possible causes. A relationship between two chart lines is a starting point for investigation, rather than proof that one caused the other.