Fuels: Super, Super Plus, E10 – These are the differences

Dusseldorf. After three years of falling fuel prices, diesel and gasoline have become significantly more expensive again in 2026. The most expensive month to refuel was September. The average price for Super E10 was 2.26 euros per liter, diesel 2.38 euros per liter. This is shown by the data from the General German Automobile Club (ADAC). The price depends on many factors, for example the cost of crude oil as well as taxes and duties. The main reason for the current high price level is the Iran War.

Gasoline and diesel fuels are both made from crude oil. The differences can be traced back to the invention of two engines: the gasoline engine (petrol engine) and the diesel engine (diesel). These two engines require different fuels due to their different functioning. For gasoline engines, there are usually four gasoline variants to choose from at gas stations in Germany.

The main difference between Super and Super Plus is the so-called research octane number (RON). It provides information about the knock resistance of a fuel - i.e. how high the proportion of iso-octane is in the mixture. Iso-octane is a synthetic hydrocarbon. The higher the octane number, the harder the fuel is to ignite and the lower the consumption.

The Super Plus mixture, on the other hand, has an even higher proportion of iso-octane. This results in a higher octane number. That's why Super Plus has a RON of 98.

(Super) E10 has been available in Germany since 2011. The “E” in the name stands for ethanol, because the fuel contains up to ten percent ethanol. According to ADAC, the ethanol content was limited to five percent before 2011 (E5). With E10, the ethanol content is 10 percent. The ethanol mixed in consists of plants grown in an environmentally friendly manner - so it is bioethanol. That's why E10 is also a biofuel and reduces CO2 emissions.

Almost all cars and motorcycles with gasoline engines can tolerate E10. Before you fill up with biofuel for the first time, you should check the compatibility of the gasoline with your vehicle's engine. This information can often be found in the tank cap or the operating instructions.

The General German Automobile Club (ADAC) has dispelled the most common prejudices against the biofuel E10. The Germans' biggest concern is the reduced lifespan of the engine due to refueling with E10. But the ADAC gives the all-clear. In a car adapted to biofuel, E10 has no influence on functional reliability, service life and wear. The club also made it clear that the E10 biofuel saves money, despite minimal additional consumption.

An E10-capable vehicle can be refueled alternately with E5 and E10. If you have filled a vehicle with E10 that is not adapted to the fuel, the amount depends on the ADAC. If only a little of the 10 percent biofuel has been filled up, topping it up with Super (E5) is enough to reduce the bioethanol content in the tank again. Once you have completely filled the tank with E10, the only option is to pump out the fuel.

Until the end of March, gas stations could change their prices as many times a day as they wanted, and there were several price spikes. Back then, refueling was usually cheapest in the early evening. The so-called 12 o'clock rule has been in effect since April 1, 2026: gas stations in Germany are only allowed to increase their fuel prices once a day, at 12 noon. They can continue to lower prices at any time.

Using price comparison sites or apps tends to save money. In these applications you can search for the cheapest gas station in any area and filter by different types of fuel. Examples of these apps are: