Loadle shows you how a country uses electricity over a typical day and asks you to name the country. This page explains where the curves come from and how they are made.
What a curve shows
Each curve is a country's average electricity demand for every hour of a typical working day, in that country's own local time, divided by the highest hour so the peak is 100%. The chart therefore shows the shape of demand, not its size, until you reveal the first clue, which switches the axis to gigawatts.
Demand here means the load the national grid actually has to meet. On most grids this is measured net of rooftop solar (or other distributed generation such as small-scale wind), which generates behind the meter and never shows up as demand. That is why some sunny countries appear to use less electricity in the early afternoon. These countries are using electricity, but making it behind the meter.
How a curve is built
- One full year of hourly (or finer) measured demand from the grid operator or regulator. Sub-hourly data is averaged within each hour, never sampled.
- Working days only. Weekends and national public holidays are removed, because the shape of a Saturday is a different puzzle. The working week is Monday to Friday except where a country's weekend falls on other days, in which case its own working week is used.
- Local time. Every curve is on the country's own clock, with daylight-saving changes handled by the source data. For a country spanning several time zones, the national total is shown on a single reference clock and the reveal text says which.
- Two puzzles per country: a winter weekday and a summer weekday. Winter is December to February and summer June to August in the northern hemisphere, the reverse in the southern hemisphere. The label uses the country's own seasons, so it never reveals which hemisphere you are in. For tropical countries the labels are those months and nothing more.
- Normalised to the peak. Each hour is divided by the highest hour of that average, so the busiest hour reads 100% and every other hour is a share of it. That is what lets a 1 GW grid and a 600 GW grid be compared by shape alone.
Data cleaning
Operator feeds sometimes report zero or a small fraction of true demand for a few hours when a measurement system is down. Hours below a quarter of the year's median are treated as missing rather than as demand. Countries where the remaining data would leave a season with fewer than thirty working days, or any hour of the day without data, are left out until a cleaner year is available.
Sources
The game currently covers countries on five continents. Every curve is derived from data published by the body that operates or regulates the grid in question: Europe's ENTSO-E Transparency Platform, national transmission system operators, energy regulators and statistical agencies, and open research datasets where no operator feed exists. Only sources whose terms allow a derived curve to be redistributed are used; data published without such terms is held back until permission is obtained.
The source and year of every curve are credited on its reveal card once you have solved or finished the day's puzzle. The countries are not listed here, since knowing the pool would spoil the game.
Most curves use the most recent complete year. A few use an older year where that is the latest the operator publishes, and the reveal text says so.
Clues
The distance and direction after each guess are measured from your guess's centroid to the answer's centroid: distance along the great circle, direction as a constant compass bearing, which matches what you would read off a map. Peak season is whichever of the winter or summer averages has the higher peak hour. The largest generation source describes the country's annual electricity mix in broad terms.
Privacy
Loadle sets no cookies. Your guesses, statistics and settings are stored in your browser only.
Licence and contact
The curve dataset is published under the Creative Commons Attribution 4.0 licence and the game's code under the MIT licence. If you work for a grid operator and would like your country included, or you think a curve is wrong, write to [email protected]. Corrections from people who know their grid are the best thing the game can receive.