Natural gas vehicles (NGV)
An NGV vehicle uses compressed natural gas to power its engine.
Gas in NGVs
Driving a Natural Gas Vehicle (NGV) is comparable to a petrol or diesel vehicle but it is cleaner for the environment and more economical to run.
Dedicated CNG engine
This engine uses natural gas as its only fuel source. It is optimised to operate on natural gas, ensuring maximum efficiency and optimum emissions results.
This engine operates on either petrol or natural gas at any one time. First the petrol is used to preheat the engine. Once the engine is hot, gas is used as the primary fuel source for the remainder of the journey. When the gas is depleted the engine will then switch back to petrol.
Dual fuel engine
This engine utilises a mixture of natural gas and diesel, with the natural gas/air mixture ignited by a diesel pilot. The diesel is injected directly into the combustion chamber, and gas is introduced into the air intake by carburation or gas injection.
How does CNG technology work?
Natural gas is transported through existing gas pipeline infrastructure to a CNG refuelling station. Here the gas is compressed and stored before being delivered to a natural gas vehicle through a natural gas dispenser.
In an NGV, gas enters the vehicle through the natural gas dispenser. It flows into high-pressure cylinders on the vehicle, and then on to the engine compartment. The gas enters the regulator and adjusts to the operating pressure of the engine's fuel-management system.
The solenoid valve allows gas to pass from the regulator into the gas mixer or fuel injectors. Natural gas then mixes with air and enters the engine's combustion chambers.
CNG vehicle applications
As a fuel, CNG is particularly suitable for use in commercial vehicles including trucks, buses, and vans. CNG provides the greatest benefits by reducing harmful emissions.
Gas Networks Ireland has conducted detailed on the ground trials with a large number of commercial truck, bus, and van fleet customers in key industry segments. These trials have resulted in positive experiences of the vehicle and its performance.