2025/2026 Hybrid Powerunit speculation

[saviour stivala]

In 2026 there will be no more energy harvesting while the ICE is under throttle, any position of the throttle pedal when being pressed, Under throttle means car is accelerating. Because the 2026 power unit, unlike the present power units, are not designed to act as a generator by using exhaust gasses when the car is under-throttle. This new for 2026 one less mode or way to harvest energy is as a consequence of not using the MGU-H.

[mzso]

Engine braking contributes to energy recovery because it is one of the three systems that decelerate the the car - (friction brakes, engine braking, and MGU-K braking). Driver-controlled engine braking will be a crucial part of the 2026 formula 1 energy recovery system, with the MGU-K specifically designed to recover energy during the moment a driver lifts off the throttle or lightly brakes in corners, even without active braking.

One in no way comes from the other. You're rather confused about what recovery means.

The rear wheels can be decelerated by three separate sources, friction from the brakes, resistance from the spinning engine (so called engine braking), and electrical braking that results from harvesting energy by the MGU-K. The driver can adjust each of these effects independently on his steering wheel.

Mostly true, but the things you said earlier is still very wrong. But there's no engine breaking as such if you can believe Tommy Cookers. I see no reason why he would make something like that up.

In 2026 the ICE will not be involved in charging the ES as the MGU-H will not be used.

Yes it will be involved.
I now realize that no-one else is reacting to you because you're probably blocked by them already. I should do the same.

[mzso]

Now imagine every lap instead of braking at 80 meters down from 300kph, you’re now lifting at 300m, then coasting for 250m, and then braking the final 50m from a much lower speed. It will look like a joke compared to what we have now.

I don't think that will happen.

Instead, the drivers will be on full throttle when the system starts energy recovery, which slows the car down, before braking hard.

There will be a balancing act between recovering under full throttle and under braking, as the former reduces the time that the brakes will be deployed and the amount of energy recovery possible.

I think that if they were allowed more freedom with the active aero there would be some interesting solutions.

For maximum energy recovery they would want to be in low drag mode for braking.

But braking performance requires the downforce for grip, which increases drag and reduces the amount of energy recovery possible.

If they were allowed continuously variable wing adjustment, rather than the 2 positions for 2026, they could adjust the rear wing to maximise rear braking and reduce drag.

So I guess they would want to recover as much as possible during turns to not compromise braking and top speed.
But I think the regen breaking is so little compared to the total that low drag mode wouldn't make a difference.

[mzso]

The trick is going to be how efficient and powerful can you make your engine. With only rear wheel recovery I doubt any car will be able to recover anywhere near 8.5MJ in a single lap. This will play out in quali as well because cars are going to have to do 2-3 laps before they will have a full battery for a single quali lap.

Why would they do that? They could just crawl around in constant regen mode. It will be amusing when someone will have less than half the power of someone doing a hot lap.
BTW aren't they allowed to fully charge the battery in the pits? Nowadays it's sometimes mentioned, but not sure if it's only for race or not.

Driving is gonna be significantly different next year. I don't think early and late brakers really gonna play into that, if that really exists. Drivers will be required to brake early, just so they can use the ICE to generate electricity. I wonder if cars will not be designed to be heavier in the rear. The more weight on the rear tires the more regenerative power, less wheel spin, rear tire wear, etc. Wonder if it will resemble the Vettel/double diffuser years. ICE will make sound at not obvious points of the track, cause drivers have over slowed down just to get back on to partial throttle to generating power. It's very complex.

Wouldn't that be more damaging to laptime then to just take away regen from full power and top speed in small bits?
Wasn't the low drag mode especially created for them to retain high speeds with low power?

And would only use full regen during normal braking with maximum breaking power.

If they viably can I'm sure they will be running the engine during turning. And if I understand correctly both the ICE and the electric generator needs to be at high RPM to do this efficiently.
So they might regularly change one gear down than it would make sense otherwise to keep the ICE near it's peak efficiency. Wherever that is.

[saviour stivala]

One in no way comes from the other. You're rather confused about what recovery means.

The rear wheels can be decelerated by three separate sources, friction from the brakes, resistance from the spinning engine (so called engine braking), and electrical braking that results from harvesting energy by the MGU-K. The driver can adjust each of these effects independently on his steering wheel.

Mostly true, but the things you said you said earlier is still very wrong. But there's no engine breaking as such if you can believe Tommy Cookers. I see no reason why he would make something like that up.

In 2026 the ICE will not be involved in charging the ES as the MGU-H will not be used.

Yes it will be involved.
I now realize that no-one else is reacting to you because you're probably blocked by them already. I should do the same.

Not reading what one would like to read can result in frustration and strain.

[wuzak]

The trick is going to be how efficient and powerful can you make your engine. With only rear wheel recovery I doubt any car will be able to recover anywhere near 8.5MJ in a single lap. This will play out in quali as well because cars are going to have to do 2-3 laps before they will have a full battery for a single quali lap.

Why would they do that? They could just crawl around in constant regen mode. It will be amusing when someone will have less than half the power of someone doing a hot lap.
BTW aren't they allowed to fully charge the battery in the pits? Nowadays it's sometimes mentioned, but not sure if it's only for race or not.

They are only allowed to store 4MJ, so that shouldn't be too difficult to achieve.

[Tommy Cookers]

... there's no engine breaking as such if you can believe Tommy Cookers....

well ....
I think I said ....
the EB is (at high rpm) about 12% of ICE power from friction losses and about 3% of ICE power from throttling losses

this proportion would be different in road cars ie low rpm and less valve overlap

[saviour stivala]

... there's no engine breaking as such if you can believe Tommy Cookers....

well ....
I think I said ....
the EB is (at high rpm) about 12% of ICE power from friction losses and about 3% of ICE power from throttling losses

this proportion would be different in road cars ie low rpm and less valve overlap

Originally You said there is no EB in F1.

[diffuser]

The trick is going to be how efficient and powerful can you make your engine. With only rear wheel recovery I doubt any car will be able to recover anywhere near 8.5MJ in a single lap. This will play out in quali as well because cars are going to have to do 2-3 laps before they will have a full battery for a single quali lap.

Why would they do that? They could just crawl around in constant regen mode. It will be amusing when someone will have less than half the power of someone doing a hot lap.
BTW aren't they allowed to fully charge the battery in the pits? Nowadays it's sometimes mentioned, but not sure if it's only for race or not.

Driving is gonna be significantly different next year. I don't think early and late brakers really gonna play into that, if that really exists. Drivers will be required to brake early, just so they can use the ICE to generate electricity. I wonder if cars will not be designed to be heavier in the rear. The more weight on the rear tires the more regenerative power, less wheel spin, rear tire wear, etc. Wonder if it will resemble the Vettel/double diffuser years. ICE will make sound at not obvious points of the track, cause drivers have over slowed down just to get back on to partial throttle to generating power. It's very complex.

Wouldn't that be more damaging to laptime then to just take away regen from full power and top speed in small bits?
Wasn't the low drag mode especially created for them to retain high speeds with low power?

And would only use full regen during normal braking with maximum breaking power.

If they viably can I'm sure they will be running the engine during turning. And if I understand correctly both the ICE and the electric generator needs to be at high RPM to do this efficiently.
So they might regularly change one gear down than it would make sense otherwise to keep the ICE near it's peak efficiency. Wherever that is.

So I'm gonna say you're probably right in some situations/tracks but not in all situations ...

[Mattchu]

BTW aren't they allowed to fully charge the battery in the pits? Nowadays it's sometimes mentioned, but not sure if it's only for race or not.

5.4.13 The amount of stored energy in any ES may not be increased by more than 100kJ whilst the
car is stationary in the pit lane or garage during the Qualifying Session or during a Race pit
stop.

[mzso]

... there's no engine breaking as such if you can believe Tommy Cookers....

well ....
I think I said ....
the EB is (at high rpm) about 12% of ICE power from friction losses and about 3% of ICE power from throttling losses

this proportion would be different in road cars ie low rpm and less valve overlap

Well, I interpreted it as insignificant. 15% of like 500HP next year vs 2,5-3 MW breaking power IIRC doesn't seem that much.

[mzso]

BTW aren't they allowed to fully charge the battery in the pits? Nowadays it's sometimes mentioned, but not sure if it's only for race or not.

5.4.13 The amount of stored energy in any ES may not be increased by more than 100kJ whilst the
car is stationary in the pit lane or garage during the Qualifying Session or during a Race pit
stop.

So that doesn't seem to apply for the ES charget at the beginning of the session. (wouldn't even make sense) So start with full charge and regen during in-laps (which I didn't even think of before)? So they'd always be near full.

[Tommy Cookers]

... there's no engine breaking as such if you can believe Tommy Cookers....

the EB is (at high rpm) about 12% of ICE power from friction losses and about 3% of ICE power from throttling losses

Well, I interpreted it as insignificant. 15% of like 500HP next year vs 2,5-3 MW breaking power IIRC doesn't seem that much.

15% of 500 hp is 56 kW
by about 190 kph there's no friction braking as grip is only enough for 350 kW regeneration and 56 kW EB
thereafter EB is costing 56 kW of regeneration

[saviour stivala]

Formula 1 cars, and I am talking about the present cars, do experience significant engine braking, though it is a combination of engine internal resistance and powerful aerodynamic drag, the engine's compression and friction slow the car when throttle is closed because the pistons continue to move compressing air in the cylinder, this requires energy and causes a resistance that slows the car down, and this effect is amplified by the car's highly aerodynamic design, which greats a strong drag force, especially at high speeds, The car's modern hybrid system, which use the MGU-K to recapture energy, also contribute a significant amount of braking.

[DenBommer]

If they add a generator on the front axle for 2026, how will this affect the racing?

Also, what would happen if they’re allowed to harvest more energy per lap? With or without the front generator