2025/2026 Hybrid Powerunit speculation

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
Badger
Badger
3
Joined: 22 Sep 2025, 17:00

Re: 2025/2026 Hybrid Powerunit speculation

Post

FW17 wrote:
06 Nov 2025, 15:01
Badger wrote:
06 Nov 2025, 11:01
FW17 wrote:
06 Nov 2025, 10:01
I dont think rules allow harvesting at full throttle.

The car at full throttle with with 450kw ICE power to the wheels travelling with the wings open at over 340kph, suddenly drops to 200kw to the wheels (because as per some posts above) and 250kw to the generator will cause a sudden drop in speed. This is enough for the car behind to slam straight into the back of the car.

The engineers would have made some stupid map that would have shown in sim to generate, top up and deploy at the exit to be faster than defending on the straight, similar to the DRS games Max and Charles were playing in the beginning of 2022 season.

Regen at max throttle is not going to be allowed.
Read the quoted rules at the top of the page maybe.
https://i.imgur.com/wMG6lTY.png

Tell me how a driver demands 218 kw halfway down the straight?
Programmable software regulates the maximum power demand, same way it does now with deployment.

Actually I think the guy who posted before used an older set of the 2026 regulations. The most recent edition I can find stipulates the following:

5.14.8 The driver maximum power demand must not be reduced at any greater than the rates defined
below:
a) 50kW in any 1s period at Competitions where the FIA determines that the power
limited distance exceeds 3500m. These Competitions and the vehicle fundamentals
used for the calculation of the power limited distance may be found in the Appendix
to the Technical and Sporting Regulations.
b) 100kW in any 1s period at all other Competitions.
Furthermore, the total power reduction is limited to a maximum of 450kW and the resulting
electrical DC power of the ERS‐K must remain above ‐100kW.


In other words, full throttle harvesting will be available but limited to -100kW.

The way they get around your worries about suddenly slowing is obviously by mandating that you gradually reduce deployment, which is covered in the same regulation above.

User avatar
BassVirolla
12
Joined: 20 Jul 2018, 23:55

Re: 2025/2026 Hybrid Powerunit speculation

Post

Badger wrote:
06 Nov 2025, 15:34
FW17 wrote:
06 Nov 2025, 15:01
Badger wrote:
06 Nov 2025, 11:01

Read the quoted rules at the top of the page maybe.
https://i.imgur.com/wMG6lTY.png

Tell me how a driver demands 218 kw halfway down the straight?
Programmable software regulates the maximum power demand, same way it does now with deployment.

Actually I think the guy who posted before used an older set of the 2026 regulations. The most recent edition I can find stipulates the following:

5.14.8 The driver maximum power demand must not be reduced at any greater than the rates defined
below:
a) 50kW in any 1s period at Competitions where the FIA determines that the power
limited distance exceeds 3500m. These Competitions and the vehicle fundamentals
used for the calculation of the power limited distance may be found in the Appendix
to the Technical and Sporting Regulations.
b) 100kW in any 1s period at all other Competitions.
Furthermore, the total power reduction is limited to a maximum of 450kW and the resulting
electrical DC power of the ERS‐K must remain above ‐100kW.


In other words, full throttle harvesting will be available but limited to -100kW.

The way they get around your worries about suddenly slowing is obviously by mandating that you gradually reduce deployment, which is covered in the same regulation above.
Well, reduced from 250 to 100kW, but still allowed.

It's been a while since I stopped posting and reading the technical regulations, because there are some posters not willing to believe not me but the governing body.

wuzak
wuzak
504
Joined: 30 Aug 2011, 03:26

Re: 2025/2026 Hybrid Powerunit speculation

Post

Badger wrote:
06 Nov 2025, 15:34
Actually I think the guy who posted before used an older set of the 2026 regulations. The most recent edition I can find stipulates the following:

5.14.8 The driver maximum power demand must not be reduced at any greater than the rates defined
below:
a) 50kW in any 1s period at Competitions where the FIA determines that the power
limited distance exceeds 3500m. These Competitions and the vehicle fundamentals
used for the calculation of the power limited distance may be found in the Appendix
to the Technical and Sporting Regulations.
b) 100kW in any 1s period at all other Competitions.
Furthermore, the total power reduction is limited to a maximum of 450kW and the resulting
electrical DC power of the ERS‐K must remain above ‐100kW.


In other words, full throttle harvesting will be available but limited to -100kW.

The way they get around your worries about suddenly slowing is obviously by mandating that you gradually reduce deployment, which is covered in the same regulation above.
I was quoting issue 13 from July, but it is the same for issue 14 from mid October.
C5.12.6 Unless the electrical DC power of the ERS-K is negative, the driver maximum power demand must not be reduced at any greater than the rates defined below:
a. 50kW in any 1s period at Competitions where the FIA determines that the power limited distance exceeds 3500m. These Competitions and the vehicle fundamentals used for the calculation of the power limited distance may be found in the document FIA-F1-DOC-Cxxx.
b. 100kW in any 1s period at all other Competitions.
Furthermore, the total power reduction is limited to a maximum of 600kW and the resulting electrical DC power of the ERS-K must remain above −250kW.
The part highlighted in red is new in Issue 14.

Issue 11 from February said:
C5.12.8 The driver maximum power demand must not be reduced at any greater than the rates defined below:
a. 50kW in any 1s period at Competitions where the FIA determines that the power limited distance exceeds 3500m. These Competitions and the vehicle fundamentals used for the calculation of the power limited distance may be found in the document FIA-F1-DOC-Cxxx.
b. 100kW in any 1s period at all other Competitions.
Furthermore, the total power reduction is limited to a maximum of 450kW and the resulting electrical DC power of the ERS-K must remain above −100kW.
Issue 12 from June said:
C5.12.6 The driver maximum power demand must not be reduced at any greater than the rates defined below:
a. 50kW in any 1s period at Competitions where the FIA determines that the power limited distance exceeds 3500m. These Competitions and the vehicle fundamentals used for the calculation of the power limited distance may be found in the document FIA-F1-DOC-Cxxx.
b. 100kW in any 1s period at all other Competitions.
Furthermore, the total power reduction is limited to a maximum of 450kW and the resulting electrical DC power of the ERS-K must remain above −100kW. These limits are changed respectively to 600kW and -250kW for the Sprint Qualifying and Qualifying sessions.

wuzak
wuzak
504
Joined: 30 Aug 2011, 03:26

Re: 2025/2026 Hybrid Powerunit speculation

Post

Badger wrote:
06 Nov 2025, 15:34
Actually I think the guy who posted before used an older set of the 2026 regulations. The most recent edition I can find stipulates the following:
The latest regulations can be downloaded from https://www.fia.com/regulation/category/110

Badger
Badger
3
Joined: 22 Sep 2025, 17:00

Re: 2025/2026 Hybrid Powerunit speculation

Post

wuzak wrote:
06 Nov 2025, 16:23
Badger wrote:
06 Nov 2025, 15:34
Actually I think the guy who posted before used an older set of the 2026 regulations. The most recent edition I can find stipulates the following:
The latest regulations can be downloaded from https://www.fia.com/regulation/category/110
Okay, I was referring to michl420's post. But reading your post it actually seems that my interpretation is the outdated one. Because it says -250kW in the later issues. So you will be able to do quite a lot of full throttle harvesting then.

mzso
mzso
69
Joined: 05 Apr 2014, 14:52

Re: 2025/2026 Hybrid Powerunit speculation

Post

FW17 wrote:
06 Nov 2025, 10:01
I dont think rules allow harvesting at full throttle.

The car at full throttle with with 450kw ICE power to the wheels travelling with the wings open at over 340kph, suddenly drops to 200kw to the wheels (because as per some posts above) and 250kw to the generator will cause a sudden drop in speed. This is enough for the car behind to slam straight into the back of the car.

The engineers would have made some stupid map that would have shown in sim to generate, top up and deploy at the exit to be faster than defending on the straight, similar to the DRS games Max and Charles were playing in the beginning of 2022 season.

Regen at max throttle is not going to be allowed.
If the regs allow it it will be, until it's changed... They set limits on how fast output power can be decreased.
wuzak wrote:
06 Nov 2025, 11:44
Why would the rpms increase when the driver lifts off/brushes the brakes and the MGUK is recovering energy?

What is the source of this "new for 2026 rules allowing energy recovery when cornering"?
How would that even be possible? The car would just speed up...

mzso
mzso
69
Joined: 05 Apr 2014, 14:52

Re: 2025/2026 Hybrid Powerunit speculation

Post

Tommy Cookers wrote:
04 Nov 2025, 02:15
for 2026 there seems to be no consumption limit ?? - only a fuel (heat) rate limit
again to help the least competitive teams give a better impression eg by having sufficient electrical energy
There is an energy limit, isn't there? Which based on the fuel blend will be calculated in to fuel mass.

wuzak
wuzak
504
Joined: 30 Aug 2011, 03:26

Re: 2025/2026 Hybrid Powerunit speculation

Post

mzso wrote:
07 Nov 2025, 01:46
Tommy Cookers wrote:
04 Nov 2025, 02:15
for 2026 there seems to be no consumption limit ?? - only a fuel (heat) rate limit
again to help the least competitive teams give a better impression eg by having sufficient electrical energy
There is an energy limit, isn't there? Which based on the fuel blend will be calculated in to fuel mass.
Not that I have seen so far.

mzso
mzso
69
Joined: 05 Apr 2014, 14:52

Re: 2025/2026 Hybrid Powerunit speculation

Post

wuzak wrote:
07 Nov 2025, 01:49
mzso wrote:
07 Nov 2025, 01:46
Tommy Cookers wrote:
04 Nov 2025, 02:15
for 2026 there seems to be no consumption limit ?? - only a fuel (heat) rate limit
again to help the least competitive teams give a better impression eg by having sufficient electrical energy
There is an energy limit, isn't there? Which based on the fuel blend will be calculated in to fuel mass.
Not that I have seen so far.
I guess I badly misremember then. So that's even more incentive to regen while turning, all the time.
Which I expect is a motivation towards ultra high rpm MGUs, so they can be reasonably efficient with low ICE rpm as well. (I do remember right that there can be a gear ratio between the ICE and the MGU, right?)

gruntguru
gruntguru
572
Joined: 21 Feb 2009, 07:43

Re: 2025/2026 Hybrid Powerunit speculation

Post

FW17 wrote:
06 Nov 2025, 15:01
Badger wrote:
06 Nov 2025, 11:01
FW17 wrote:
06 Nov 2025, 10:01
I dont think rules allow harvesting at full throttle.

The car at full throttle with with 450kw ICE power to the wheels travelling with the wings open at over 340kph, suddenly drops to 200kw to the wheels (because as per some posts above) and 250kw to the generator will cause a sudden drop in speed. This is enough for the car behind to slam straight into the back of the car.

The engineers would have made some stupid map that would have shown in sim to generate, top up and deploy at the exit to be faster than defending on the straight, similar to the DRS games Max and Charles were playing in the beginning of 2022 season.

Regen at max throttle is not going to be allowed.
Read the quoted rules at the top of the page maybe.
https://i.imgur.com/wMG6lTY.png

Tell me how a driver demands 218 kw halfway down the straight?
He would need to lift his right foot to a "part-throttle" position.

Now - tell me why you want to know. The table I created shows how part-throttle harvesting is regulated by the FIA. I doubt that it will be applicable halfway down the straight.
Last edited by gruntguru on 07 Nov 2025, 03:14, edited 1 time in total.
je suis charlie

wuzak
wuzak
504
Joined: 30 Aug 2011, 03:26

Re: 2025/2026 Hybrid Powerunit speculation

Post

mzso wrote:
07 Nov 2025, 01:57
wuzak wrote:
07 Nov 2025, 01:49
mzso wrote:
07 Nov 2025, 01:46


There is an energy limit, isn't there? Which based on the fuel blend will be calculated in to fuel mass.
Not that I have seen so far.
I guess I badly misremember then. So that's even more incentive to regen while turning, all the time.
Which I expect is a motivation towards ultra high rpm MGUs, so they can be reasonably efficient with low ICE rpm as well. (I do remember right that there can be a gear ratio between the ICE and the MGU, right?)
Maximum MGUK speed is limited.

C5.18.5 The relative rotational speed between any two parts of the MGU-K may not exceed 60,000rpm.

gruntguru
gruntguru
572
Joined: 21 Feb 2009, 07:43

Re: 2025/2026 Hybrid Powerunit speculation

Post

mzso wrote:
07 Nov 2025, 01:37
wuzak wrote:
06 Nov 2025, 11:44
Why would the rpms increase when the driver lifts off/brushes the brakes and the MGUK is recovering energy?
What is the source of this "new for 2026 rules allowing energy recovery when cornering"?
How would that even be possible? The car would just speed up...
True. The driver will need to select a gear that creates appropriate rpm through the corner to meet his harvesting requirements. e.g. if maximum harvesting is required, they will have to corner in a gear that sets the rpm above 10,500.
je suis charlie

gruntguru
gruntguru
572
Joined: 21 Feb 2009, 07:43

Re: 2025/2026 Hybrid Powerunit speculation

Post

saviour stivala wrote:
06 Nov 2025, 11:13
I have explained more than once the new for 2026 rules allowing energy recovery when cornering, It seems these recovery when cornering are new, meaning this mode was not there before. Anyhow, once again: New regulations allow for MGU-K to recover energy during cornering, which is a change from previous years, this mode will happen by special maps, which triggers MGU-K into harvesting, even when driver lifts off throttle or is slightly using the brake pedal, these maps will increase engine revs (rpm) during this harvesting mode.
Engine revs cannot be controlled by maps. The driver selects a gear then engine revs will match the road speed for that particular gear.
je suis charlie

gruntguru
gruntguru
572
Joined: 21 Feb 2009, 07:43

Re: 2025/2026 Hybrid Powerunit speculation

Post

saviour stivala wrote:
06 Nov 2025, 11:13
. . . It seems these recovery when cornering are new, meaning this mode was not there before.
As shown by Wuzak above - there is NO MENTION of harvesting "during cornering" in the Technical Regulations. The Technical Regulations do mention harvesting in "partial load".

They also provide a formula giving the limits for partial load harvesting at any given load demand. (The Regulations (erroneously) use the term "engine power" to indicate the partial load demand. The term "PU output", "driver demand" or "power demand" would be more correct.)
Image
.
If you apply the formula above, using a few examples of "driver demand", you can calculate roughly how much harvesting will be available for each.
Image
.
My interpretation of the regulation is "for any driver demand less than full throttle, the control system may harvest at a rate given by the formula given in 5.4.5. For example if the mode selected is "maximum harvest" and the driver demand is 150 KW to the tyres, it is permitted to use fuel at the rate of 2336 MJ/hr which is equivalent to approximately 325 KW from the ICE. Since the driver only wants 150 KW at the tyres, the MGU-K will harvest at 175 KW.
.
I would be interested to hear your interpretation of this regulation (if different to mine).
je suis charlie

saviour stivala
saviour stivala
48
Joined: 25 Apr 2018, 12:54

Re: 2025/2026 Hybrid Powerunit speculation

Post

gruntguru wrote:
07 Nov 2025, 05:07
saviour stivala wrote:
06 Nov 2025, 11:13
I have explained more than once the new for 2026 rules allowing energy recovery when cornering, It seems these recovery when cornering are new, meaning this mode was not there before. Anyhow, once again: New regulations allow for MGU-K to recover energy during cornering, which is a change from previous years, this mode will happen by special maps, which triggers MGU-K into harvesting, even when driver lifts off throttle or is slightly using the brake pedal, these maps will increase engine revs (rpm) during this harvesting mode.
Engine revs cannot be controlled by maps. The driver selects a gear then engine revs will match the road speed for that particular gear.
Yes, engine revs are controlled indirectly by engine maps in formula 1, which are data tables within the ECU that manages how engine produce power in response to driver input. While the maps don't directly ''set'' a specific rev count, they control the torque output at different engine speeds and throttle positions, which determines the engine rev behavior, drivers can select different maps to change the throttle's response , for example, to have less aggressive map in wet conditions to prevent wheelspin, which keeps engine from revving to high. Engine maps are primarily a function of engine speed (RPM) and throttle position, defining how much torque the engine should deliver. The ECU uses these maps to manage the engine power output, affecting how the car accelerates and reaches different RPM'S.