If you were in charge of balancing supply and demand, how would you do it? How would you balance the needs of people to heat and light their homes, hospitals, schools, factories, and offices with the need to reduce overall energy consumption and shift the remaining energy generation from environmentally harmful to environmentally friendly sources?
All the numbers are totals for a whole year, not a snapshot. They are based on the latest published UK data - electricity generation for 2025 (provisional) and energy consumption for 2023 - converted to Thousand Tonnes of Oil Equivalent (ktoe) for comparison purposes. Real generation and consumption rise and fall through the day and across the seasons: wind and solar output depends on the weather, and heating demand is far higher in winter than in summer. The annual figures hide those swings. Every slider starts at the annual figures.
To make fine-tuned adjustments, select a slider and use the arrow keys on your keyboard (Page Up and Page Down take bigger steps).
Electricity generated per year
Energy consumed per year
Energy gap per year
Consumption met by electricity
Every number on this page is a total for a whole year, and real generation and consumption fluctuate through the day and the seasons. The electricity dial shows the total electricity generated over the year. The generation section is purely about electricity: how much of it each source produces. The consumption dial shows all the energy used in the UK over the year in every form, not just electricity but also petrol, diesel, aviation fuel and gas for heating. The energy gap is the difference between the two: the energy that is currently supplied by burning fossil fuels directly, in vehicles, boilers and industry, rather than coming from electricity. The black mark on each dial shows its starting value. Click or tap any dial to put it, and the sliders it adds up, back to their starting values.
Your task is to reduce the energy gap to zero by matching electricity generated to total energy consumed, so that no fossil fuels are burned at all, whether to generate electricity or directly in vehicles and boilers.
These sliders are purely about generating electricity. The power station dials at the top show the number of individual power stations or generation farms of each type generating 20MW or more (0.00172ktoe). Generation figures are annual totals for 2025 (provisional). In practice, wind, solar and hydro output varies with the weather and the seasons, and gas and imports are among the sources that fill the gaps.
Existing stations of 20MW or more are solid shapes. Extra ones you add are outlined and placed near existing stations of the same type, to show the visual effect rather than predict where they would go. Shetland is moved into the dashed box.
Consumption figures are annual totals for 2023, the latest year in the published tables. Actual use varies through the year: heating demand, for example, is far higher in winter. Where the published data allows, the slider uses an everyday measure instead of ktoe, such as miles travelled per person or kWh per household, with the ktoe equivalent shown beneath it. The dials stay in ktoe so that everything adds up.
This shows how Great Britain is generating its electricity right now, in the current half hour. It is a snapshot, whereas everything else on this page is a total for a whole year, so only the shares of each source can be compared, and even those will differ. The mix changes all the time: wind and solar rise and fall with the weather and the time of day, demand peaks in the evening and in winter, and gas and imports fill the gaps. Look again at different times of day and in different seasons to see how much it moves.
How the figures were put together: all figures are totals for a whole year. Travel and household measures are those annual totals expressed as an average per person, per week or per household, and the heating temperature slider scales a whole year's heating using a typical winter. Electricity figures are the fuel used to generate electricity, as in Energy Trends table 5.1, so wind, solar and hydro count one-for-one whilst gas, nuclear and bioenergy include the heat lost in generation. Imports are net imports. Other sources includes the small amount of coal and oil used to generate electricity, and the oil-fired power stations are not shown on the map. Power station counts include only stations of 20MW or more run by major power producers. Industrial manufacture and repair is industry's total consumption less its heating and lighting. Road passenger and road freight divide the 2023 road total using their shares in 2022, the latest year those are published. Travel sliders use 2022 passenger-kilometres and the UK population (67.6 million in 2022), and a long-haul return is London to New York, about 11,100 km; air travel is an average across all passengers departing the UK, so in practice a minority take most of the flights. Domestic space heating is set by the typical winter living-room temperature: heating energy is taken to follow the gap between that temperature and the outdoor temperature (the Midlands winter average for 2020 to 2026, 5.2\u00b0C), less about 3.8\u00b0C of free heat from people, appliances and sunshine, so each degree is worth roughly 10% of heating at the starting figures. The temperatures are those rooms actually reach, as measured in the Energy Follow-Up Survey, which is not the same as the dial setting. Hot water and appliance sliders divide domestic consumption by 28.4 million households (1 ktoe is 11.63 GWh). Starting values are rounded, and energy changes in proportion to the measure.
This is of course an oversimplification, but it gives users a general idea of the complexities involved. Further data refinement will be added in due course. For people who care about cookies, the only cookies going on here are Google Analytics ones.
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Made with the help of Claude from the original Energytron.