AdBlue: the clean secret of modern diesel vehicles

02 August 2024

There is a name that is becoming increasingly familiar among drivers: AdBlue. It is a key element for modern diesel vehicles, yet there are still many uncertainties and questions about it. AdBlue is a solution made of 32.5% technical urea (a chemical substance derived from ammonia) and 67.5% demineralized water. It is neither a fuel nor an additive: it is stored in a separate tank from diesel and used in vehicles with SCR (Selective Catalytic Reduction) technology to reduce nitrogen oxide emissions, pollutants that contribute to air pollution and are harmful to human health

How does AdBlue work?

In practice, when AdBlue is injected into a vehicle’s exhaust system, it reacts with the hot exhaust gases. This chemical reaction converts nitrogen oxides into harmless nitrogen and water vapor, two non-polluting compounds. This results in a significant reduction of harmful emissions, allowing diesel vehicles to comply with strict Euro 6 regulations.

Who produces AdBlue?

AdBlue is a trademark registered by the German Association of the Automotive Industry (VDA), but the product itself can be manufactured by various producers. However, chemical companies that produce it must meet strict quality standards and advanced synthesis processes to obtain a pure, impurity-free product, which is essential for the proper functioning of SCR systems. It is available at service stations (in dispensers and canisters), in auto parts stores (canisters and bottles), in supermarkets, and of course online. Prices may vary, but on average range between €0.50 and €1.50 per liter.

How much AdBlue is consumed?

From the consumer’s perspective, there are two or three basic facts worth knowing. AdBlue consumption is low, about 3% of fuel consumption, so a full tank lasts a long time. Several factors affect consumption (driving style, road conditions, temperature, etc.), but on average, about 2 liters of AdBlue are needed every 1,000 kilometers. Modern vehicles alert the driver when the level is low, but it is important not to forget to refill: vehicles compliant with Euro 6 regulations do not allow the engine to restart once it has been turned off and the AdBlue has run out. In such cases, the vehicle will need to be taken to a service center for a system reset and refueling.