Diesel on LPG - who benefits from such a gas installation? Guide

The recent rise in diesel prices has increased interest in gas-fired diesel engines. Check what kind of transformation it is.

The idea of ​​burning LPG in a diesel engine is not new. In Australia, this technology has been used in commercial vehicles for many years. Thus, operating costs are reduced.

In an era where the price of diesel has equaled the price of gasoline, autogas refueling is also starting to make a profit in diesel passenger cars. However, the state of high mileage.

LPG calculator: how much you save by driving on autogas

Three systems

Diesel engines can run on LPG in a variety of ways. One of them is the conversion of a diesel unit into a spark ignition engine, i.e. working like a petrol unit. This is a mono-fuel system (single fuel) - running only on autogas. However, this is a very expensive solution, since it requires a complete overhaul of the engine. Therefore, it is only used for working machines.

The second system is dual-fuel, also known as gas-diesel. The engine is powered by limiting diesel fuel injection and replacing it with LPG. Diesel fuel is supplied in an amount that allows spontaneous combustion in the cylinder (from 5 to 30 percent), the rest is gas. Although this solution is cheaper than monopropellant, it is also associated with significant costs. In addition to the installation of a gas plant, a system for limiting the dose of diesel fuel is also required.

See also: Gas installation on a car - which cars are better with HBO

The third and most common system is diesel gas. In this solution, LPG is only an additive to diesel fuel - usually in a proportion: 70-80 percent. diesel fuel, 20-30 percent autogas. The system is based on a gas plant, similar to that used for gasoline engines. Thus, the installation kit includes an evaporator reducer, an injector or gas nozzles (depending on engine power) and an electronic control unit with wiring.

How does it work?

The main dose of diesel fuel is injected into the combustion chambers of the engine, and an additional portion of gas is injected into the intake system. Its ignition is initiated by a self-igniting dose of oil. Thanks to the addition of gaseous fuel, diesel fuel consumption is reduced, which reduces fuel costs by about 20 percent. This is because the addition of gas allows diesel fuel to burn better. In a conventional diesel engine, due to the high viscosity of OH and excess air, complete combustion of the fuel is almost impossible. For example, in units with a Common Rail system, only 85 percent. the mixture of diesel fuel and air burns completely. The rest is converted into exhaust gases (carbon monoxide, hydrocarbons and particulate matter).

Since the combustion process in the diesel gas system is more efficient, the engine power and torque are also increased. The driver can regulate the intensity of gas injection into the engine by pressing the accelerator pedal. If he presses it harder, more gas will enter the combustion chamber, and the car will accelerate better.

See also: Gasoline, diesel, LPG - we calculated which is the cheapest drive

Up to 30% power increase is possible in some turbocharged engines. more than rated power. At the same time, the improvement in the operating parameters of the engine does not adversely affect its resource, since they are the result of almost complete combustion of the fuel. Improved combustion results in carbon-free cylinders and piston rings. In addition, the exhaust valves, the turbocharger are clean, and the life of the catalysts and particulate filters is significantly extended.

How much does it cost?

In Poland, the most commonly used are three units operating in a diesel gas system. These are Elpigaz's DEGAMix, Car Gaz's Solaris and Europegas' Oscar N-Diesel.

See also: New LPG vehicles - comparison of prices and installations. Guide

Prices for the installations of these manufacturers, designed for cars and many vans, are similar and range from PLN 4 to 5. zloty. Thus, the cost of assembling a LPG system for a diesel engine is not small. Therefore, interest in these systems among car users is low.

LPG calculator: how much you save by driving on autogas

According to the expert

Wojciech Mackiewicz, editor-in-chief of the industry website gazeeo.pl

– Running the engine on diesel and natural gas is a very efficient system. This not only saves operating costs, but is also cleaner for the environment. Greater engine efficiency (increase in power and torque) is also of great importance. At the same time, the durability and operational reliability of the drive is higher, since the installation does not interfere with the operation of the motor controllers. However, installing HBO on a diesel engine is beneficial only when the car has a high annual mileage and it is best for him to drive outside the city. The specificity of these systems is such that they work most efficiently when the engine is running with the same load. For this reason, LPG diesel plants are used in road transport.

Wojciech Frölichowski