The consumption of AdBlue is 3-4 percent that of fuel consumption for a Euro 4 engine, and 5-7 percent for a Euro 5 engine, depending on driving, load and road conditions. AdBlue tanks are available in a variety of sizes depending on vehicle and need. With a Euro 4 engine, 40 litres of AdBlue will last as long as 1000 litres of diesel fuel. With a 125 litre tank, you can cover no less than 10,000 km before it is time to fill up with AdBlue.