The cars are lighter, the tires roll better, electronic injection, turbochargers, valves…
No, we’re not talking about reducing pollution, or switching to hybrids or electrics.
The focus is on cars powered by fuels and yours energy efficiency. In other words, cars started to drive longer (and better) without needing more gasoline or diesel.
Figures from the US Environmental Protection Agency show that fuel efficiency increased by 35.4% between 2002 and 2022. In general, there are fewer failures, fewer “chokes”, fewer breakdowns, as cars become more recent.
Behind were many cars that constantly lost power, or consumed much more fuel. Today, engines are much more efficient.
But how? The summarizes the changes in 9 points.
Lighter cars. And more aerodynamic and with tires that roll better. And here physics comes in: a heavier car has greater inertia, therefore it needs more energy to move.
Electronic injection. It’s better than the carburetor or manifold. The fuel was no longer mixed with air before entering the cylinder, something that created problems and failures.
Direct fuel injection. Thus, the air enters alone and the gasoline only enters at the exact time, quantity and place; no losses.
Turbocompressores. More air in the cylinder, greater power, pistons with less work to do to pull the air-fuel mixture into the combustion chamber, smaller engines, greater efficiency.
Thermal efficiency in engines. Over the years, this fraction of the fuel’s chemical energy that is converted into useful mechanical power on the engine shaft has improved.
Valves. More specifically, variable valve control, which allows the opening/closing time of valves to be adjusted according to operational needs.
Start-stop. When we are stopped in a queue, at a traffic light… A constant waste of fuel is left behind in those moments. The technology turns off the engine when the car is stopped.
More biofuels. Mixture of ethanol with gasoline and biodiesel with diesel. Ethanol increases the octane rating of the mixture, efficiency increases.
Chemical refinement of fuels. Which is becoming more and more accurate. Less sulfur, less metals and certain aromatics, which took energy away from the main combustion.
