2026 Hybrid Powerunits

[peewon]

It also spins up the compressor at low rpm to boost ICE power.

This remind me that Ferrari actually went to the FIA last year to warn them about the start without MGU-H and were ignored so they built their PU to account for that, only for Mercedes to start complaining once the season started and then immediately a change was brought in.

[gearboxtrouble]

Even without any improvements in energy recovery relative to 2025, the system could harvest on the order of 1 MJ during a full-throttle straight. Applying a one-third reduction to account for the lower ICE output expected in 2026 still yields approximately 0.67 MJ, equivalent to ~2 seconds of MGU-K deployment at maximum power down the same straight. Even when the battery is completely depleted, it could directly drive the MGU-K with about 100MJ/130HP while the ICE is at full throttle.

Extrapolated over a full lap, this corresponds to roughly 4 MJ of recoverable energy, which translates to ~12 seconds of additional 350 kW (≈470 hp) MGU-K deployment. That's something.

Imho 12s a lap of extra full throttle seems a tad too optimistic and even if it was realistic we'd still only cover 20-40% of the full throttle time around a lap. Would it help with the current formula? yes. Would it be the solution that fixes it? absolutely not. You're still left with 550-580 hp ICEs for most of the lap and thats the biggest driver of all of the main problems with this ruleset from the yo yo overtakes to the closing speeds to the sacrifice of cornering performance to boost harvesting. The problem remains energy starvation from the lack of energy input. At this stage, adding a spec MGU-H would be too complex, costly and provide far too little extra energy. The only realistic fix doable by 2027 is to boost the ICE to at least 75% of the 1000hp target and lower the MGU-K by 60% to ensure that brake energy alone is all that is needed to have full power available nearly all the time. A 750hp ICE would require a fuel flow boost and some material but manageable changes to the internals, turbo and chassis to handle the extra fuel - something modders do to their cars every day.

I started talking about the MGU-H because we’ve begun to see a rethinking of it in production cars and motorcycles. The latest iteration is a three-cylinder Honda motorcycle engine. I thought it was a shame that arguably the most famous Formula 1 innovation was removed from the formula. My argument was never that it was the solution to our current woes, although it clearly wouldn’t hurt.

Fair. I agree it was the one engine innovation F1 perfected in the last ruleset though iirc it was BMW who first created a road car with a prototype triple turbo 3.0 inline 6 diesel with a MGUH in the early 2000s. My guess is we'll see a lot more of this as euro 7 regs bite to help make back the power lost from the lamba one regs. The rumor is the next Porsche 911 GT3 will be forced to abandon the glorious 4.0 NA flat 6 for some sort of electrically turbocharged 3.6 engine tuned to rev to the moon.

[hollus]

It also spins up the compressor at low rpm to boost ICE power.

This remind me that Ferrari actually went to the FIA last year to warn them about the start without MGU-H and were ignored so they built their PU to account for that, only for Mercedes to start complaining once the season started and then immediately a change was brought in.

That maybe a convenient narrative, but the Macca's started every bit as good as the Ferraris in the last race. Sounds more like learnings taken than inherent hardware limitations.

[Farnborough]

It also spins up the compressor at low rpm to boost ICE power.

This remind me that Ferrari actually went to the FIA last year to warn them about the start without MGU-H and were ignored so they built their PU to account for that, only for Mercedes to start complaining once the season started and then immediately a change was brought in.

That maybe a convenient narrative, but the Macca's started every bit as good as the Ferraris in the last race. Sounds more like learnings taken than inherent hardware limitations.

Haven't McLaren taken a low first gear ratio too in expectation of this eventuality ?

The effect of getting the clutch fully closed (released and fully driving the gearbox) at that track speed, will allow wider throttle opening and earlier pressure build in compressor to raise torque.

[Tommy Cookers]

I started talking about the MGU-H because we’ve begun to see a rethinking of it in production cars and motorcycles. The latest iteration is a three-cylinder Honda motorcycle engine. I thought it was a shame that arguably the most famous Formula 1 innovation was removed from the formula. My argument was never that it was the solution to our current woes, although it clearly wouldn’t hurt.

Fair. I agree it was the one engine innovation F1 perfected in the last ruleset though iirc it was BMW who first created a road car with a prototype triple turbo 3.0 inline 6 diesel with a MGUH in the early 2000s. My guess is we'll see a lot more of this as euro 7 regs bite to help make back the power lost from the lamba one regs. The rumor is the next Porsche 911 GT3 will be forced to abandon the glorious 4.0 NA flat 6 for some sort of electrically turbocharged 3.6 engine tuned to rev to the moon.

a part-time electrically assisted turbocharger (or electrically-driven supercharger) isn't really an MGU-H

an MGU-H isn't cheap and it isn't a goldmine ....
the recovered energy will be very small if the CR/ER is high and the fueling is lean
that's why the recovered energy was large in the Wright Turbo-Compound (and the efficiency unbeaten for 50 years)

supercharging (& assisted-charge NA) were first available in 'over-the-counter' cars (and aeroplanes) 100 years ago
and already dominant in car racing on both sides of the Atlantic
in 100 years there has not been a textbook claiming better efficiency at high % power (eg for turbocharged SI engines)
despite the NA engines apparent obligation to eschew knock sensing and good quality fuel and charge cooling

exhaust-driven supercharging was adopted only for convenience
GM road cars (Chevrolet Corvair and Pontiac Tempest) started this in 1959
the owners having to buy the necessary water/methanol fluid from the dealers

[peewon]

It also spins up the compressor at low rpm to boost ICE power.

This remind me that Ferrari actually went to the FIA last year to warn them about the start without MGU-H and were ignored so they built their PU to account for that, only for Mercedes to start complaining once the season started and then immediately a change was brought in.

That maybe a convenient narrative, but the Macca's started every bit as good as the Ferraris in the last race. Sounds more like learnings taken than inherent hardware limitations.

The change was made to the start procedure after it was apparent in Barcelona that the Ferrari PUs with its smaller turbo were quicker off the blocks. George Russell had a moan about it in the press and then they added the pre start 5 second delay thing so others could spool their turbos which nullified Ferrari's advantage. All this after Ferrari went to FIA with problem, were ignored and designed their turbos smaller compromising performance over a race distance for better starts. What am I missing?

[hollus]

And without those 5 seconds Macca would not have started as well as the Ferrari. That's the story line? And we know this how? It is only those 5 seconds making Ferrari not rule the world? What am I missing?

The everything Mercedes is shady, everything Mercedes is cheaty, Mercedes has everyone and everything in their pockets... it is a tiresome narrative. And with so many spaguetti thrown at that wall, sure there must be some truth to some of it, but everything, everywhere, all the time? Come on.

This particular flavor of Mercedes cheating, ejem, lobbying itself into an advantage, is only one side of the narrative you are pushing. I am just replying to this one side: If the Maccas can start equally to the Ferraris now, it -probably- could start equally also without that five second difference. So -likely- not a hardware limitation. Which is what you claim the 5 seconds rescued Mercedes out of.

I am not a Mercedes fan, far from it, but the Star Wars analogies do not convince me that they are Darth Vader and the Emperor combined. And we all know how that story ended!

[Brahmal]

The PU is interesting in isolation because its made up of so many compromises to meet purely performative marketing led benchmarks. It does not belong in F1 and has made a mockery of the sport. Motorsports formulas should be fairly simple. FE is about pushing BEV technology and should always be all electric. WEC should be about maximizing efficiency and hybrids are ideal for this purpose. F1 should be about going as fast as is safe for the drivers and a full ICE (maybe with a small electric push to pass) is the only solution able to guarantee that.

This is an important idea, that each racing series should have it's own niche with how it relates to general technology and the wider automobile industry. Internal combustion engines probably won't completely disappear from the Earth in the future. There will continue to be applications where it still makes sense to use in the medium term at least, whether it's burning sustainable biofuel, or hydrogen, or something that we haven't invented yet. Long-haul trucking, light and long-haul aviation, operations in remote areas or in undeveloped countries, I'm sure there are many more I'm not thinking of.

Mazda in particular has done a lot of work on hydrogen IC engines and other alternatives, some of which would piggyback on wherever the trucking industry decides to go, because they believe that a true sportscar (Miata) should have some sort of ICE for a whole number of reasons. F1 could use this thought-process as another justification to continue with ICE for the future. It's not going away, so may as well own it.

[diffuser]

The PU is interesting in isolation because its made up of so many compromises to meet purely performative marketing led benchmarks. It does not belong in F1 and has made a mockery of the sport. Motorsports formulas should be fairly simple. FE is about pushing BEV technology and should always be all electric. WEC should be about maximizing efficiency and hybrids are ideal for this purpose. F1 should be about going as fast as is safe for the drivers and a full ICE (maybe with a small electric push to pass) is the only solution able to guarantee that.

This is an important idea, that each racing series should have it's own niche with how it relates to general technology and the wider automobile industry. Internal combustion engines probably won't completely disappear from the Earth in the future. There will always be applications where it still makes sense to use, whether it's burning sustainable biofuel, or hydrogen, or something that we haven't invented yet. Long-haul trucking, light and long-haul aviation, operations in remote areas or in undeveloped countries, I'm sure there are many more I'm not thinking of.

Mazda in particular has done a lot of work on hydrogen IC engines and other alternatives, some of which would piggyback on wherever the trucking industry decides to go, because they believe that a true sportscar (Miata) should have some sort of ICE for a whole number of reasons. F1 could use this thought-process as another justification to continue with ICE for the future. It's not going away, so may as well own it.

I think ICE days are numbered. I'm sure the ICE cars already out there will continue to exist for years to come, but ICE sales will keep dropping. The current price of gas—and how it got there—is already accelerating the shift, and it will continue to accelerate as battery technologies improve, allowing for faster charging and higher energy density. Cars with a range of 1,000 km are right around the corner. ICE can't compete with LNG or hydrogen for generating electricity, especially when those can be combined with free electricity from solar, hydro, nuclear, and wind, making overall efficiency approach 80%.

[mzso]

F1 should be about going as fast as is safe for the drivers and a full ICE (maybe with a small electric push to pass) is the only solution able to guarantee that.

Don't open this can of worms again. This is just not true.

There will always be applications where it still makes sense to use, whether it's burning sustainable biofuel, or hydrogen, or something that we haven't invented yet. Long-haul trucking, light and long-haul aviation, operations in remote areas or in undeveloped countries, I'm sure there are many more I'm not thinking of.

"Always" is a strong word. With come concentrated effort it could have already been superseeded in most/all applications.
For long haul trucking and aviation, fuel cells would be more efficient. Propfans would be more efficient for starters and electric motors are well suited for that.
Burning costly hydrogen or biofuel is big waste of precious energy.

"Undeveloped countries" is not really an application, just a lack of ability/opportunity.

[bananapeel23]

I think ICE days are numbered. I'm sure the ICE cars already out there will continue to exist for years to come, but ICE sales will keep dropping. The current price of gas—and how it got there—is already accelerating the shift, and it will continue to accelerate as battery technologies improve, allowing for faster charging and higher energy density. Cars with a range of 1,000 km are right around the corner. ICE can't compete with LNG or hydrogen for generating electricity, especially when those can be combined with free electricity from solar, hydro, nuclear, and wind, making overall efficiency approach 80%.

ICE will always remain due to lower infrastructure requirements and the ability to bring fuel with you, which makes them better for off the grid use. But they will likely continue to be increasingly hybridized.

Road cars will increasingly become electrified, but a full transition hinges on infrastructure build-outs and battery densities and degradation rates improving to the point that manufacturing costs fall below ICE powered vehicles, since poorer regions will just stick to ICE if not.

Also I highly doubt that shipping will move away from fossil fuels until we find a way to replace the massive engines with fusion reactors, so combustion engine tech will remain relevant.

[gruntguru]

. . exhaust-driven supercharging was adopted only for convenience . .

No efficiency benefit?
At low boost levels there is little efficiency benefit but adding an exhaust turbine recovers lost energy even if recovery is limited to that required to run the supercharger.

Efficiency benefits of turbocharging over supercharging increase with pressure ratio (boost) and AFR (eg diesel and F1) - see below.
Pressure ratio. As PR increases, the contribution of positive pumping work (during the intake stroke) to brake power also increases. The corresponding increase in exhaust back pressure does not create a proportional increase in negative pumping work during the exhaust stroke.

AFR. As AFR increases, the PR must increase to produce the additional airflow required. (see Pressure Ratio above)

[diffuser]

I think ICE days are numbered. I'm sure the ICE cars already out there will continue to exist for years to come, but ICE sales will keep dropping. The current price of gas—and how it got there—is already accelerating the shift, and it will continue to accelerate as battery technologies improve, allowing for faster charging and higher energy density. Cars with a range of 1,000 km are right around the corner. ICE can't compete with LNG or hydrogen for generating electricity, especially when those can be combined with free electricity from solar, hydro, nuclear, and wind, making overall efficiency approach 80%.

ICE will always remain due to lower infrastructure requirements and the ability to bring fuel with you, which makes them better for off the grid use. But they will likely continue to be increasingly hybridized.

Road cars will increasingly become electrified, but a full transition hinges on infrastructure build-outs and battery densities and degradation rates improving to the point that manufacturing costs fall below ICE powered vehicles, since poorer regions will just stick to ICE if not.

Also I highly doubt that shipping will move away from fossil fuels until we find a way to replace the massive engines with fusion reactors, so combustion engine tech will remain relevant.

I was talking just about cars for F1 relevance. Why would Honda, Audi, Merc, etc invest in F1 in a world that does not power it's cars with ICEs.

[mzso]

ICE will always remain due to lower infrastructure requirements and the ability to bring fuel with you, which makes them better for off the grid use.

Fuel cell vehicles EVs could do that, with better efficiency.

Why would Honda, Audi, Merc, etc invest in F1 in a world that does not power it's cars with ICEs.

For the same reasons they do now, and did before.

[diffuser]

ICE will always remain due to lower infrastructure requirements and the ability to bring fuel with you, which makes them better for off the grid use.

Fuel cell vehicles EVs could do that, with better efficiency.

Why would Honda, Audi, Merc, etc invest in F1 in a world that does not power it's cars with ICEs.

For the same reasons they do now, and did before.

Honda did say they came back because of F1's road relevance. Which means they wouldn't if F1 wouldn't keep being relevant. Honda doesn't need to spend 170 Million of it's 7 or 8 billion of R&D on F1.