Does the material of petrol fuel tank affect fuel consumption?

Yes, the material of a petrol fuel tank can affect fuel consumption, although the impact is relatively indirect and may not be as significant as some other factors. Here's how:

Heat insulation properties: Different materials have different heat insulation capabilities. For example, plastic fuel tanks generally have better heat insulation performance than metal ones. Since petrol expands when heated, if the fuel tank is easily affected by external heat, the petrol inside will expand, resulting in a certain amount of fuel vaporization. This vaporization can lead to increased pressure in the tank, and some of the fuel vapor may be released into the atmosphere through the ventilation system. Over time, this can cause a slight increase in fuel consumption. Plastic tanks, with their better heat insulation, can help reduce this effect to a certain extent, thereby helping to maintain fuel economy.
Weight of the vehicle: The weight of the fuel tank also matters. If the fuel tank is made of a heavy material like steel, it will increase the overall weight of the vehicle. A heavier vehicle requires more energy to move, which means the engine has to work harder and consume more fuel. In contrast, lightweight materials such as high - density polyethylene (HDPE) used in some modern fuel tanks can help reduce the vehicle's weight, which is beneficial for improving fuel efficiency. However, it should be noted that the weight of the fuel tank is just one of the many factors affecting vehicle weight, and its impact on fuel consumption is relatively small compared to the total weight of the vehicle and other major components.
Internal surface smoothness: The internal surface of the fuel tank can affect the flow of fuel. Some materials may have a smoother internal surface, which allows the fuel to flow more freely. This can ensure a more stable fuel supply to the engine, helping the engine to operate more efficiently and potentially reducing fuel consumption. In contrast, if the internal surface of the tank is rough, it may cause some resistance to the fuel flow, which could have a minor impact on the engine's fuel - burning efficiency.