Electricity prices are no longer a fixed number on your monthly bill. In a growing share of European countries, the price you pay per kilowatt-hour changes every hour, driven by wind output in the North Sea, solar generation in Spain, demand spikes during cold snaps, and cross-border trade between national grids. If your contract is indexed to spot prices — common in Finland, Sweden, Norway, the Netherlands, and increasingly in Spain and Germany — the difference between running your dishwasher at 18:00 versus 02:00 can be 5x to 10x in cost.
Wattora is a free iOS app that surfaces this data in a form a normal person can act on. It pulls live and day-ahead electricity prices directly from the ENTSO-E Transparency Platform — the official data source for European electricity markets — and shows them as a colour-coded hourly chart on your home screen. No account, no ads, no subscription.
How to Use Wattora
Setup is two taps. Download Wattora free from the App Store, open the app, and select your country or bidding zone. ENTSO-E covers more than thirty European zones, so most users will find their region in the list on the first try.
The main view is an hourly bar chart for today and tomorrow. Each bar represents one hour of the day. The vertical axis is the spot price in EUR per megawatt-hour, which translates to roughly a tenth of a cent per kilowatt-hour at the smaller end of the scale. Bars are colour-coded: green hours are cheap (typically below the rolling average), amber hours are medium, and red hours are expensive peaks.
Tap any bar to see the exact price and time. The app uses your device's locale to display the price in the appropriate currency formatting, and the time always reflects your local timezone, so you do not need to convert from CET in your head.
Tomorrow's prices appear in the app after ENTSO-E publishes them, usually between 13:00 and 14:00 CET each day. This is the same data window that the day-ahead auction settles on, so once it appears, the prices are locked — what you see in Wattora at 14:00 is exactly what you will pay for tomorrow's consumption if your contract is fully indexed.
How to Save Money Using Electricity Spot Prices
The economics only work if your contract is indexed to spot prices. In a flat-rate contract, you pay the same per kilowatt-hour at 03:00 as at 19:00, and Wattora is informational rather than actionable. Dynamic spot-price contracts are the default in Finland and Norway, common in Sweden and Denmark, and growing share in the Netherlands, Spain, and Germany. Check your contract before assuming — the savings live or die on this single point.
The practical pattern is to shift high-consumption loads to the cheapest two to four hours of the day. The biggest movers are the dishwasher, the washing machine, the dryer, the EV charger, and the water heater. A typical household dishwasher uses around 1.5 kWh per cycle, an EV charger pulls 7 to 11 kW continuously while charging, and a hot water heater can draw 15 to 30 kWh on a heavy day.
The price spreads are larger than people expect. On a windy night in Finland, prices can go negative — producers paying you to consume because the grid has too much wind power to absorb. On a cold, still evening in February, prices can spike above 200 EUR per MWh. A 10x to 20x spread between cheapest and most expensive hour is normal, and on a few days per year, the spread is greater than 50x.
The rule of thumb is that the overnight window from 01:00 to 06:00 is cheapest on average across most European zones. But the app shows the exact hours, and they shift seasonally. In summer, midday hours are often cheaper than evenings because of solar overproduction. In winter, the price floor stays during the night and the evening peak (17:00 to 21:00) becomes expensive.
Check tomorrow's prices every evening at 14:00 or later, after the day-ahead auction settles. Set your dishwasher's delay-start timer to the cheapest hour the app shows. Over a year, this single habit can shift one to two euros of consumption per day into cheap hours — 400 to 700 EUR annual savings on a typical household contract.
How Wattora Compares to Other Electricity Price Apps
Wattora is not the only app in this space, but it covers the broadest geographic range with the lowest friction. Most competitors either require an electricity contract with a specific provider or restrict coverage to a single country.
| App | Price data | Countries | Free | Notifications |
|---|---|---|---|---|
| Wattora | ENTSO-E live | 30+ European | Yes | Planned |
| Tibber | Live (provider) | Nordic + some EU | Contract required | Yes |
| aWATTar | Live | Austria, Germany | Yes | Yes |
| Stromliste.de | Web only | Germany | Yes | No |
Tibber is the closest commercial competitor but only useful if you also become a Tibber electricity customer. aWATTar is excellent but restricted to two countries. Stromliste.de is web-only and German-only. Wattora is the only option that gives you full ENTSO-E coverage in a free, no-account iOS app.
Reading the ENTSO-E Data
If you want to understand what Wattora is actually showing you, a quick primer on the underlying market helps. The ENTSO-E Transparency Platform is a regulatory data feed published by the European Network of Transmission System Operators for Electricity. It includes the day-ahead clearing prices from each national bidding zone — the prices set in a daily auction where electricity producers offer supply and large consumers bid demand for each hour of the next day.
The price you see is in euros per megawatt-hour at the wholesale level. For a household contract, your actual cost per kilowatt-hour will add taxes, grid fees, retailer margin, and renewable surcharges — typically doubling or tripling the headline price. But the variation between hours is what Wattora highlights, and that variation passes through directly to a spot-priced contract.
Frequently Asked Questions
What is Wattora and how does it get electricity prices?
Wattora displays real-time and day-ahead electricity spot prices from the ENTSO-E Transparency Platform, the official European electricity market data source. Prices are in EUR/MWh and update hourly. There is no account, no ad-tracking, and no subscription — the app downloads public market data and renders it as a chart.
Which countries are supported in Wattora?
Wattora covers most European countries connected to the ENTSO-E grid, including Germany, France, Spain, Finland, Sweden, Norway, the Netherlands, Italy, Denmark, Belgium, Austria, Switzerland, Poland, Portugal, Ireland, and others. Coverage depends on ENTSO-E data availability for each bidding zone. Some countries are split into multiple zones (Sweden has four; Norway has five) — the app lets you select the specific zone you live in.
Do I need a special electricity contract to use Wattora?
No. Wattora shows market prices for anyone to read. The savings only materialise if your electricity contract is indexed to spot prices, which is common in Nordic countries and increasingly available in Spain, Germany, and the Netherlands. On a flat-rate contract, the app is informational — useful for understanding market dynamics but not for reducing your bill.
When are day-ahead electricity prices published?
ENTSO-E publishes next-day prices daily at approximately 13:00 to 14:00 CET, after the day-ahead auction settles. Wattora updates automatically once they are available, so you can plan tomorrow's high-consumption tasks by checking the app at around 14:00 each day.
Download Wattora
Wattora is free on the App Store, with no account required and no subscription. The app works on iPhone and iPad and runs on iOS 16 and newer.
