Formula 1 car engines are incredibly efficient. They put out a whopping 1000+ horsepower while only having a 1.6-liter capacity. So we know they’re powerful, but how do F1 engines manage to be so efficient?
F1 engines are efficient due to the research and development that has been put into them over the years. A complex hybrid system also helps make them very efficient through energy recovery. F1 engines are the most efficient car engines on the planet, reaching 50% thermal efficiency (or more).
These incredibly efficient engines came about with the 2014 engine regulation changes. In the article below, I’ll discuss how F1 engines have become so efficient and what we can expect in the next decade of Formula 1.
How Efficient Are F1 Engines?
F1 engines are said to be around 50% efficient in terms of thermal efficiency. The current F1 engines are not only the most efficient in the sport’s history, but they are also some of the most powerful, with the hybrid system helping them produce more than 1000 horsepower.
But what exactly does thermal efficiency mean?
When an F1 car burns fuel, you turn the fuel (in the form of hydrocarbons) into heat energy. If you could capture all of this energy and turn it into useful mechanical work, that would be 100% conversion efficiency. When an F1 car is going down a straight at full throttle with the maximum fuel flowing into the engine, about 54-56% of that fuel’s chemical energy can be turned into mechanical energy to move the car forward.
In the V8 era, before the 2014 hybrid engine regulation changes, the rules controlled engine performance by restricting the capacity and maximum rpm. This encouraged teams to develop high-power rather than high-efficiency engines. Teams focused on maximizing the amount of air they could get into their engines, regardless of how much fuel they needed to burn along with it.
This led to rich air-fuel mixtures and high revving engines – not overly efficient ones. In fact, thermal efficiency figures of the V8 engines used until 2013 were closer to 29%.
Get as much air in as possible, match that with more fuel, and burn it. That was the way to increase power. This resulted in engines running much faster, because more bangs means more power! The teams always tried to run their engines faster, survive those high rpms, and then try to reduce the losses. And they used however much fuel they needed.
But the introduction of the fuel flow limit in 2014 meant that teams could no longer do this.
Fuel Flow Limits
You could put as much air in as you want, but now you could only send a certain amount of fuel into the engine in a given amount of time. It was therefore all about efficiency now, as teams could only add so much fuel to the engine, and they needed to get as much energy out of that as possible.
This led to lean mixtures of about 20:1 (air:fuel). Lean burn combustion is not an easy thing though, as it increases the risk of knocking, which disturbs the combustion process. In a turbocharged engine (like the ones that came back in 2014), because of the higher thermal loads, the risk is even higher.
To be able to get the best out of the lean mixtures and to make the most of the energy in the fuel, completely new combustion systems were developed. Of course, the hybrid system also helps the engine in a Formula 1 car provide more power and become more efficient overall, but I’ll go into more detail on that after dealing with the combustion engine itself.
How F1 Engines Became So Efficient
For the introduction of the 2014 rules, F1 teams focused every possible effort on optimizing the combustion chamber as well as the dynamics of how the combustion process itself took place. As direct injection was now permitted (with V8 only port injection was permitted), teams had the capability to precisely control how the fuel enters the combustion chamber to achieve a more optimal burn.
Teams could now use high pressure injectors with many nozzles, which allowed them to inject very small droplets over a short time. They aspired to put those droplets in exactly the right place at the right time within the combustion chamber. Mercedes introduced a new technology called Turbulent Jet Ignition or Pre Chamber Ignition (which played a large part in their dominance over the next 8 years).
Mercedes’ Ignition Techniques
With Pre-Chamber Ignition, 95-97% of the fuel is injected as normal, but there is a small pre-chamber with a spark-plug, and up to 5% of the fuel is added there (now with a rich burn mixture) and ignited. It becomes a high pressure jet of hot gases that enters the cylinder, igniting the rest of the now well-mixed fuel more homogeneously throughout the cylinder, with more air per given amount of fuel.
Less energy was wasted as heat and more energy was converted to work, making the Mercedes engines incredibly efficient (and therefore better able to produce more power from the now-limited amount of fuel they could send into the engine).
Ferrari followed in 2015, as their supplier Mahle already worked on such a system, and Renault followed in 2016. But Mercedes was able to maintain a development advantage until 2020. This combustion process was responsible for the biggest efficiency gains. Mahle says that this technologie improves fuel efficiency by 10-25% and thermal efficiency by 10%!
With instantaneous gas temperatures of 2600°C during combustion (4712°F) and exhaust temperatures in excess of 1000°C (1832°F), there is a lot of heat given off as a result of the combustion in an F1 engine. One big contributor to the heat in an engine is friction, and a lot of effort was invested into optimizing materials, coatings, bearings, lubrications and seals.
Various (mainly secretive) materials and coatings brought gains in thermal efficiency and friction reduction, and of course there was a lot of development of the engine oils and other lubricants.
Friction within the electrical components was minimized too, and innovative (and secret) technologies were used to cool the rotors of magnets to reduce ohmic losses in windings, while silicon carbide was improved for use in the inverters. There were lots of smaller innovations, and different teams tried different things (with varying levels of success).
As a result of all of these innovations and better combustion techniques, teams improved the efficiency of F1 engines from about 29% to around 46%. But one of the most significant parts of the regulations overhaul was the introduction of the hybrid powertrain. These hybrid components helped raise the engine’s efficiency by a few extra percent.
How The Hybrid System Helps F1 Engines Be More Efficient
The hybrid system in an F1 car is made up of many components, but the first of these I’ll discuss is the MGU-H. The MGU-H sits between the compressor and the turbine (which sucks in large amounts of air feeding the inlet port with high pressure oxygen), so when these spin, so does the MGU-H.
Note: I’m not going to go into too much detail about how the various hybrid components work in this article. For more on that, see our full guide to the hybrid system in F1.
Along with storing energy in the energy store, deploying it to the MGU-K, or spinning up the compressor to reduce the turbo-lag, the MGU-H can be used to carefully control the compressor to improve torque delivery and driveability. In this way, teams can utilize direct injection to optimize the delivery of the fuel, and they can use the MGU-H to optimize the delivery of the oxygen. Controlling the boost and engine behavior that way also gave efficiency gains.
The MGU-H is expensive, and it’s very complex, which means that there is a high probability of something going wrong. This is why the MGU-H is set to be dropped from the power units in the future. But the other component of the hybrid system is here to stay – the MGU-K.
This is a motor generator unit at the rear of the car, which helps recover energy under braking. Essentially, when the driver is decelerating, the unit turns some of the waste kinetic energy into electrical power, sending it back to the energy store (or the MGU-H). The unit can also function as a motor, helping turn the wheels under acceleration.
This component helps make the car’s powertrain more efficient by taking advantage of some kinetic energy that would otherwise have been lost through heat at the brakes and tires. However, even when combined with the MGU-H, the hybrid components only account for a few percent of the overall efficiency, with most of it coming from the combustion engine itself.
What Increased Efficiency Meant For The Fuel Tanks
An interesting side effect of F1 engines getting more efficient is that the fuel tanks shrunk dramatically. In the previous engine regulations when the cars still used V8 engines, the fuel tanks were nearly double the size of what they are now. Modern Formula 1 cars have a 30-gallon fuel tank and can use no more than 110 kilograms of fuel in order to complete the race distance of around 190 miles.
In the past, F1 cars used twice as much fuel to complete the same distance. Getting 190 miles on 30 gallons of fuel might not sound like much when you compare it to your average road car, but it’s important to remember these drivers do not drive their cars efficiently (even if the engine itself is efficient). Instead, they drive them as fast as possible to get the best result in the race!
Are F1 Engines More Efficient Than Road Cars?
Modern F1 engines are more efficient than road cars. If we compare the thermal efficiency of an F1 car’s engine to that of the average road car, F1 engines are sometimes twice as efficient. Road cars might reach thermal efficiency of 20-25%, but F1 car engines reach 54-56%.
Thermal Efficiency vs Fuel Efficiency
If we’re looking at thermal efficiency, we find the average road car is even worse than the previous generation of Formula 1 cars. The average road car has a thermal efficiency of just 20%, significantly less than the 54-56% of modern Formula 1 cars. Thermal efficiency is basically a measure of how much power the engine can put out for a given amount of energy put into it.
In terms of distance, the average road car can drive much farther than a Formula 1 car in direct comparison. However, F1 cars are built purely for speed and performance. The faster you drive, the more fuel you consume. If a road car was to be driven flat out, it would struggle to make the 190-mile race distance on 30 gallons of fuel!
Key Fact: No other car can get as much performance out of the same amount of fuel as an F1 car
Are F1 Engines The Most Efficient?
F1 engines are the most efficient combustion engines used in cars. F1 engines reach thermal efficiency figures above 50%, which is far more than any other road or race car on the planet.
Will F1 Engines Become More Efficient In 2026?
Whether F1 engines will become more efficient in 2026 will depend on the impact of the next set of engine regulations. New engine regulations are brought in every decade or so, and each change comes with its own set of challenges that the engineers need to overcome.
The next set of engine regulations are coming into place in 2026 and will aim to make the current generation of F1 engines even more efficient. The cars will be more reliant on the hybrid systems, with the hybrid components providing even more of the overall power of the car. The efficiency of the engines will therefore likely grow even higher when these engines are brought into place.
In addition to the increase in hybrid power in 2026, teams will also need to use 100% renewable fuels in their cars. Formula 1 cars are currently using E10 fuel, which means that 90% of the fuel mix comes from fossil fuels and the other 10% is ethanol.
Ultimately, the combination of renewable fuel and an increase in hybrid power will lead to a greener and more environmentally friendly motorsport, which is Formula 1’s end goal. However, it will take a lot of work from the engineers to make this happen successfully.
F1 engines are some of the most fuel-efficient petrol engines on the planet. They are so efficient thanks to the decades of research and development that has helped the combustion engine become the most efficient car engine on the planet. The hybrid power train also helps make the power unit more efficient too.
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