2025/2026 Hybrid Powerunit speculation

[wuzak]

Even at Monaco and Singapore, they will not get to the 8.5MJ/lap limit on braking alone.

While they have a lot of time on the brakes, especially Singapore, not all of it is hard braking where 350kW could be recovered from the rear.

At Singapore I'm sure they will happily use most of the recovered energy for acceleration, and potentially run out by the end of the lap.

At Monaco, they may not be able to use all of it. 8.5MJ is just over 25s @ 350kW, and Monaco is a track with a lap time of approximately 75s and 50% at full throttle, so it may be possible, but they also may lower the speed at which the ramp down occurs, which means less energy used for a lap.

[carisi2k]

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.

[diffuser]

How much could the new regs favor late or early brakers? As far as I know from our Formula Student car, longer and lighter braking is better for energy recovery while later and shorter braking is more reliant on the mechanical braking system but worse for recovery.

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.

[Rodak]

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.

Doubtful. From the 2026 Technical REgulations:

C4.2 Mass distribution
At all times during the Qualifying and Sprint Qualifying Sessions, with the car resting on a
horizontal plane:
i. the mass measured at the front axle must not be less than the Minimum Mass specified in
Article C4.1 factored by 0.44.
ii. the mass measured at the rear axle must not be less than the Minimum Mass specified in
Article C4.1 factored by 0.54.

[diffuser]

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.

Doubtful. From the 2026 Technical REgulations:

C4.2 Mass distribution
At all times during the Qualifying and Sprint Qualifying Sessions, with the car resting on a
horizontal plane:
i. the mass measured at the front axle must not be less than the Minimum Mass specified in
Article C4.1 factored by 0.44.
ii. the mass measured at the rear axle must not be less than the Minimum Mass specified in
Article C4.1 factored by 0.54.

Thanks for that..but that means...

i. Front Axle
The mass measured at the front axle must be at least 44% of the Minimum Mass.

Using 798 kg as an example:
798×0.44=351.12kg
- So the front axle must support at least 351.12kg.

ii. Rear Axle
The mass measured at the rear axle must be at least 54% of the Minimum Mass.

Again with 798 kg:
798×0.54=430.92kg
→ So the rear axle must support at least 430.92kg.

So it can shift the weight backwards.

[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.

They cannot store more than 4MJ, so getting the battey full for a qualifying lap shouldn't be hard.

They do it now with only 120kW MGUK.

No track on the F1 calendar has enough braking to recover 8.5MJ on a lap. Most have 10-15s of braking, not all of which would allow 350kW of rear wheel recovery.

Singapore would have the closest to the braking time required (25s), but much isn't heavy enough.

So they will have to use the ICE to recover during part throttle and under full throttle at the end of straights.

At the faster, longer, tracks which have limited braking recovery, like Silverstone and Spa, will likley have a lower amount of recovery allowed.

[Rodak]

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.

Doubtful. From the 2026 Technical REgulations:

C4.2 Mass distribution
At all times during the Qualifying and Sprint Qualifying Sessions, with the car resting on a
horizontal plane:
i. the mass measured at the front axle must not be less than the Minimum Mass specified in
Article C4.1 factored by 0.44.
ii. the mass measured at the rear axle must not be less than the Minimum Mass specified in
Article C4.1 factored by 0.54.

Thanks for that..but that means...

i. Front Axle
The mass measured at the front axle must be at least 44% of the Minimum Mass.

Using 798 kg as an example:
798×0.44=351.12kg
- So the front axle must support at least 351.12kg.

ii. Rear Axle
The mass measured at the rear axle must be at least 54% of the Minimum Mass.

Again with 798 kg:
798×0.54=430.92kg
→ So the rear axle must support at least 430.92kg.

So it can shift the weight backwards.

I'm not sure what you mean by shift weight backwards; these front/rear mass requirements have been in effect for years. Yes, there is a little bit of play, but one can't really 'shift' weight backwards. Frankly, if I were designing a car I'd want front/rear balance to be free to help solve under/over steer issues, but here we are.

[diffuser]

Doubtful. From the 2026 Technical REgulations:

Thanks for that..but that means...

i. Front Axle
The mass measured at the front axle must be at least 44% of the Minimum Mass.

Using 798 kg as an example:
798×0.44=351.12kg
- So the front axle must support at least 351.12kg.

ii. Rear Axle
The mass measured at the rear axle must be at least 54% of the Minimum Mass.

Again with 798 kg:
798×0.54=430.92kg
→ So the rear axle must support at least 430.92kg.

So it can shift the weight backwards.

I'm not sure what you mean by shift weight backwards; these front/rear mass requirements have been in effect for years. Yes, there is a little bit of play, but one can't really 'shift' weight backwards. Frankly, if I were designing a car I'd want front/rear balance to be free to help solve under/over steer issues, but here we are.

Move the balance rearward. Reduce understeer by going in to the corner slower but getting on the throttle early.

[carisi2k]

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.

They cannot store more than 4MJ, so getting the battey full for a qualifying lap shouldn't be hard.

They do it now with only 120kW MGUK.

No track on the F1 calendar has enough braking to recover 8.5MJ on a lap. Most have 10-15s of braking, not all of which would allow 350kW of rear wheel recovery.

Singapore would have the closest to the braking time required (25s), but much isn't heavy enough.

So they will have to use the ICE to recover during part throttle and under full throttle at the end of straights.

At the faster, longer, tracks which have limited braking recovery, like Silverstone and Spa, will likley have a lower amount of recovery allowed.

No they don't recover 4MJ with the KERS.They recover 2MJ and sometimes can't even do that. The other 2MJ is recovered with the MGU-H.

[TimW]

The very short braking distance is actually one of the problems of F1, it makes overtaking more difficult. With longer braking distance and regen, that may very well help the spectacle. Drivers can choose to sacrifice regen for a shorter braking distance, to defend or to make an overtake. Regen and deployment strategy becomes much more important.

“The spectacle” isn’t just about the quantity of overtakes. The cars need to be impressive to watch when they aren’t overtaking as well, and massive LiCo into every corner doesn’t exactly scream “pinnacle” to me.

Personally I think overtaking quantity is highly overrated. If it were the number of overtakes that determined how entertaining a motorsport was then F1 would have never become the top motorsport brand. It should be possible to overtake, but also possible to defend from a slightly faster car. That balance is key to F1.

Never said it was about the quantity, but if braking distances are something like 10 car lengths, it becomes very difficult to gain a car length compared to your competitor under braking. So you end up with only push button fly by overtakes, with are indeed of little value.

I'd much prefer the cars to be smaller with less downforce. I'd sacrifice ultimate performance for better natural (non- artificial) raceability. If I watch pre 2017 F1, with the smaller cars, it does not look less impressive to me.

[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.

They cannot store more than 4MJ, so getting the battey full for a qualifying lap shouldn't be hard.

They do it now with only 120kW MGUK.

No track on the F1 calendar has enough braking to recover 8.5MJ on a lap. Most have 10-15s of braking, not all of which would allow 350kW of rear wheel recovery.

Singapore would have the closest to the braking time required (25s), but much isn't heavy enough.

So they will have to use the ICE to recover during part throttle and under full throttle at the end of straights.

At the faster, longer, tracks which have limited braking recovery, like Silverstone and Spa, will likley have a lower amount of recovery allowed.

No they don't recover 4MJ with the KERS.They recover 2MJ and sometimes can't even do that. The other 2MJ is recovered with the MGU-H.

Yeah, I forgot that!

[saviour stivala]

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

[michl420]

I think it is impossible that they will have problems with a "too" full battery. "If" they had too much electrical energy they can always make less power with the ICE and save fuel.

[saviour stivala]

I think it is impossible that they will have problems with a "too" full battery. "If" they had too much electrical energy they can always make less power with the ICE and save fuel.

The MGU-K will be able to recover up to 8.5mj per lap. The ES has a maximum allowed state-of-charge (SoC) of 4mj. The increased recovery capacity requires more complex management systems, as teams must continuously deploy energy from the ES (battery) to stay within the 4mj limit and prevent energy waste.

[wuzak]

I suspect that the points of the track where the most braking energy is recovered is just before where they will deploy most of the energy - i.e. braking from high speed into slow corners.

Something I've been wondering about as a recovery strategy is part or low load recovery.

Take the hairpin at Monaco, for example.

Currently the drivers go through there completely off throttle, the engine producing minimal power.

In 2026 there is the possibility of energy recovery in that corner.
Maybe they recover 100kW - the ICE produces 100kW and the MGUK recovers 100kW, for a net output of 0kW.

After the corner there is a short burst down the hill to the next corner.
In the current PUs they have to go from, essentially, 0kW to the desired power.

For 2026 the ICE is already making 100kW, so its a matter of quickly reducing the MGUK recovery and, possibly, changing to deployment, to get the desired output.

Possibly could be an area of performance advantage for 2026 over 2025, providing quicker acceleration?

Or do the engines ramp up to power too quickly for there to be any noticeable difference?

It certainly should mitigate turbo lag.