The market offers three types of diesel and each of them is identified with a letter: A, B and C. The first two are practically available at any gas station, although only the A, the highest quality, is indicated for use in cars and other vehicles equipped with engines with diesel technology.
Diesel B or subsidized is mainly used for agricultural machinery and certain boats, while diesel C is designed for use in heating boilers or heat production equipment due to its high paraffin content. Its use is strictly prohibited for cars and boats.
Due to its characteristics, diesel A is the most expensive fuel of the three. It is specifically designed for automotive diesel engines. It is more refined and contains additives. This type of fuel, which is marketed in two variants (diesel and premium or plus diesel), provides various benefits. On the one hand, it reduces consumption and polluting emissions; and on the other, it increases engine performance and protects the pump and injection system.
Diesel B is a subsidized fuel that is not intended for any type of vehicle. It has a minor degree of refinement that makes it not suitable for cars, motorcycles, trucks or vans. But it is suitable for tractors and some industrial engines. It is also used in non-recreational boats and special unregistered vehicles.
Being subsidized, agricultural diesel is cheaper than the other two. Its price is lower than diesel A and C because it is designed to feed a work tool, hence its acquisition is more regulated and controlled. To buy agricultural diesel, you must prove that you are in possession of the corresponding authorization.
Each type of diesel is a certain color. Only diesel A retains the original green-yellow hue; dyes are added to the other two fuels to distinguish them. Thus, B or agricultural diesel oil is reddish in color and C has a bluish hue.
The coloration of the fuel according to its use is carried out to avoid fraud. Especially so that the drivers of a vehicle with authorization to circulate on the public road do not feed the engine of their car with subsidized diesel. This is a fraudulent practice that persecutes the traffic agents of the Guardia Civil carrying out random checks.
To check the type of diesel used in a vehicle, agents take a fuel sample. If it is reddish in color, it means that it is agricultural diesel, so there are signs of fraud. When this occurs, the sample is deposited in a sealed and authenticated container for subsequent analysis in the laboratory and proceedings are opened against the offender.
This is an infraction included in the Organic Law 38/1992, on Excise Taxes, according to the Civil Guard, which recalls that the fraudulent use of this type of diesel in vehicles in which it is not allowed is considered a Crime of Fraud to the Public estate. The fine ranges from 600 to 12,000 euros.
