Hrvatski
Loss of power
One of the most widespread myths is the statement that a car that runs on natural gas loses almost 20% of its power. This is only partly true. Power was lost in the early stages of mass methanization of transport – in the 1970s and 90s.
During that time, the factory production of gas vehicles was limited and the basis of the fleet of gas-cylinder vehicles were converted vehicles; engine control systems were based on mechanical systems; car factories were responsible only for cars, and supplier companies were responsible for gas equipment; there was no qualified service system for gas equipment.
In these conditions, small firms, which carried out re-equipment in private garage boxes, showed the “miracles” of engineering. They often customized gas equipment (for both propane and methane) for a specific engine and machine without documentation, guarantees and spare parts.
In such conditions, the deterioration of engine performance could not be avoided. At the same time, not only mechanical, but also environmental indicators, often suffered.
With the introduction of electronic control systems and the beginning of mass factory production (original equipment manufacturing) of gas-cylinder vehicles, these problems have passed. Today it is almost impossible to distinguish a petrol or diesel car model from its gas version. The same power, dynamics, carrying capacity and passenger capacity. At the same time, methane-fueled vehicles are favorably distinguished by low noise levels, lower emissions and fuel savings.
Short mileage per fill
This disadvantage was also inherent to natural gas machines decades ago. This mainly applied to passenger cars. It was difficult to place enough cylinders on them to travel a long enough distance on methane. A 50-liter cylinder under a pressure of 200 atmospheres contains from 10 to 12 m3 of natural gas. With an engine consumption of 7-10 liters of oil fuel per 100 km, the converted car could travel 150-200 km. More cylinders could be fitted on trucks and buses. But, since the fuel consumption was also higher than that of light vehicles, the mileage per refueling was also 200-300 kilometers.
Modern passenger cars with CNG cylinders integrated into the main body and a fuel consumption of 5-6 l/100 km can travel up to 450 kilometers on methane. And taking into account the stock of gasoline, which is available on almost all models, the total mileage for one refueling (methane + gasoline) can be 900-1000 kilometers. Trucks and buses equipped with balloon cassettes can travel between gas stations from 400 to 1000 km.
LNG trucks and buses can cover greater distances at just one fill. Compared to CNG, their mileage per gas station is 2.5 times higher.
Duration of the refueling process
Modern gas filling equipment makes it possible to refuel a car, bus or truck with compressed natural gas in almost the same time as their counterparts with gasoline or diesel fuel. For filling cars with compressed natural gas, fuel nozzles of the NGV1 type are used. To increase the refueling speed of heavy equipment, NGV2 fuel nozzles with an increased bore are used.
It takes 10 minutes to refuel a diesel-powered freight truck. It takes exactly the same amount of time to refuel with compressed or liquefied natural gas.
Problems with refueling time at CNG stations arise when you have to refuel heavy-duty vehicles through pistols for passenger vehicles.
Bomb in the car
Sometimes you can hear that a gas cylinder is a “bomb in a car”. The fact that methane is a fire and explosive gas is no secret. It requires respectful attitude and qualified handling. Although extremely rare, much less frequently than with propane or gasoline vehicles, incidents with natural gas vehicles do occur.
Natural gas is not easy to ignite. For this to happen, it is necessary that its concentration in the air is from 5 to 15%. In addition, it has the highest autoignition temperature: 540°C. Comparison of natural gas for these indicators with propane, gasoline and diesel fuel shows that it is the safest type of motor fuel.
As you know, automotive CNG cylinders are very durable. For example, on a passenger car, the cylinders are installed in the statistically least vulnerable parts of the car. According to BMW, cylinders integrated into the car body are much safer than gasoline or diesel tanks or propane tanks.
There are frequent cases when, after a serious accident or fire, automobile cylinders filled with gas remained unharmed. The safety system was triggered (a bursting disc valve – triggered by a sharp jump in pressure and a valve with a fusible link – triggered when the temperature rises) and natural gas was vented into the atmosphere.
