2025/2026 Hybrid Powerunit speculation

[diffuser]

I am not so sure if a slightly higher ICE efficiency will really be decisive. Yes, a few extra kJ in the acceleration phase will mean extra kJs recovered, meaning in the next straight you have extra electrical energy as well. Also it will give more battery charging in the off throttle phases.
BUT better aero efficiency will have exactly the same effect. Less energy lost in acceleration and coasting phases will mean more recovery, less drag in off throttle phases will mean more opportunity to charge the battery.
The same goes for electrical efficiency, and even mechanical grip helps.

"slightly" is a word that can mean many things to different people. If I define "slightly" as being able to start Silverstone with 10kg of less fuel than everyone else, yet still have the same power and range. That is huge.

10 kg would be >5% less fuel. That would still require almost 5% higher ICE efficiency (almost because of the effect of a 1.2% lower starting weight). It is nonsense that the gain would be more than the efficiency gain (you can turn the argument around, if you take a bit extra fuel, you can burn more fuel in acceleration, recover more, and harvest more in off throttle. The extra mass even allows to regenerate more during braking.... )

Realistic differences are much smaller. And again: Aero efficiency will have exactly the same effect. Less aero losses means there is more energy available to recover. Always!

Set aero aside; this is a PU discussion. There is no regulation that prevents a team with the most efficient power unit from also having the most efficient aerodynamic package.

The only inherent downside of carrying additional fuel is the mass penalty. There are no regulations limiting total fuel load, only the rate at which fuel may be consumed (fuel flow). Under the current regulations, the ICE is permitted to charge the ES, and as a result, the ICE can consumption fuel to generate electrical energy. However, the constraint on ICE-based energy harvesting is not fuel availability, but rather the operating conditions and opportunities presented by the circuit.

These opportunities are track-dependent and are governed by factors such as throttle demand, engine operating points, and energy management strategy. In simple terms, when the ICE is required to deliver higher mechanical power for acceleration, less surplus power is available to drive the MGU-K for battery charging (noting this is a high-level simplification).

Therefore, increasing fuel load does not directly translate into increased energy harvesting potential, as energy recovery is ultimately limited by deployment demands and available operating windows rather than total fuel mass. However, a more efficient ICE will definitively allow the car to start with a lower fuel load.

[mzso]

Will we see front generation in 2027 with 30 kg increase in weight?

How would we? The regs have been settled a long time ago.

You may not like to hear it, but V8 in 2030 probability is low.

This formula is going to continue like the previous one for some time, better FIA goes on to improve the regeneration at earliest.

First you ask, then you're an oracle?
I see little or no chance for engines to change before 2030, whether that will be an augmentation or a complete break, remains to be seen. Unless this year will be a disaster I can't see everyone agreeing on an engine reg change. Whoever's on top, will block any attempt, as usual.

As for V8's I see little chance for them to ever appear again. Too many cylinders for modern turbo hybrids, and too inefficient as a high rpm NA engine.

[diffuser]

How would we? The regs have been settled a long time ago.

You may not like to hear it, but V8 in 2030 probability is low.

This formula is going to continue like the previous one for some time, better FIA goes on to improve the regeneration at earliest.

First you ask, then you're an oracle?
I see little or no chance for engines to change before 2030, whether that will be an augmentation or a complete break, remains to be seen. Unless this year will be a disaster I can't see everyone agreeing on an engine reg change. Whoever's on top, will block any attempt, as usual.

As for V8's I see little chance for them to ever appear again. Too many cylinders for modern turbo hybrids, and too inefficient as a high rpm NA engine.

I wouldn't suggest they use logic to come to these decisions.

[wuzak]

If everyone were confident it would a flow rate of 3000 mj fuel and a tank limit of 3000 mj a race.

I am not sure 9MJ will be able to be deployed lap after lap. Why make it a limiting factor in racing where it going to be longer braking distances, statergised by teams when this element can be removed with the additional generation from the front wheels.

The 30 kg weight gain can be even knocked off from the race fuel allocation from 100 kg to 70 kg

There isn't a race fuel limit.
Because they want do battery charging with the engine

They dropped the race fuel limit from the previou sgeneration rules (2014-2025) a while ago.

The recovery limit is 8.5MJ on most tracks, 9.0MJ when 1s behind another car at a detection point, deployment is unlimited.

Front regen doesn't get you a lot more recovery unless the total recovery power is increased.
it will get you as much as from the rear

I mean in terms of energy recovered.
If the total recovery power is 350kW, there will be a slight improvement in energy recovered.
If you double the recovery power, then you will double the energy recovery.

But if you have more power with a front MGU, then the 4MJ battery will drain a lot more quickly.
who said power the front?

If it is only for generation, will it be worth the weight?
A similar effect could be achieved in the 2026 regulations by having the recovery power of 350kW, but a deployment power of 200kW or 250kW.

[TimW]

"

Set aero aside; this is a PU discussion. There is no regulation that prevents a team with the most efficient power unit from also having the most efficient aerodynamic package.

The only inherent downside of carrying additional fuel is the mass penalty. There are no regulations limiting total fuel load, only the rate at which fuel may be consumed (fuel flow). Under the current regulations, the ICE is permitted to charge the ES, and as a result, the ICE can consumption fuel to generate electrical energy. However, the constraint on ICE-based energy harvesting is not fuel availability, but rather the operating conditions and opportunities presented by the circuit.

These opportunities are track-dependent and are governed by factors such as throttle demand, engine operating points, and energy management strategy. In simple terms, when the ICE is required to deliver higher mechanical power for acceleration, less surplus power is available to drive the MGU-K for battery charging (noting this is a high-level simplification).

Therefore, increasing fuel load does not directly translate into increased energy harvesting potential, as energy recovery is ultimately limited by deployment demands and available operating windows rather than total fuel mass. However, a more efficient ICE will definitively allow the car to start with a lower fuel load.

My original post was addressing the incorrect belief with many that somehow this ruleset makes ICE power / efficiency much more important than in previous regulations. That somehow regeneration amplifies the benefit. It does not. With similar strategies, a 1% ice benefit will result in a 1% benefit in electrical power. I.e. a 1% benefit of your total power. The same as it would have been with an ICE only powertrain.

I guess you missed the wink on carrying extra fuel.

[Tommy Cookers]

re. "ICE efficiency with the 30% reduction in fuel power" ....
isn't the answer an 1100cc V4 conversion ??

re. "350 kW front-axle G-only UK to double recovery" ....
electric-only braking below 140 kph is a can of worms and ....
because the GU-K is running at low voltage and high current its efficiency is poor ....
(the existing MGU-K uses the 8-speed gearbox to keep its voltage high and its current low)

yes (IMO) front-axle generation-only is a good advert for almost any arrangement of .... 4wd

[FW17]

re. "ICE efficiency with the 30% reduction in fuel power" ....
isn't the answer an 1100cc V4 conversion ??

re. "350 kW front-axle G-only UK to double recovery" ....
electric-only braking below 140 kph is a can of worms and ....
because the GU-K is running at low voltage and high current its efficiency is poor ....
(the existing MGU-K uses the 8-speed gearbox to keep its voltage high and its current low)

yes (IMO) front-axle generation-only is a good advert for almost any arrangement of .... 4wd

[diffuser]

"

Set aero aside; this is a PU discussion. There is no regulation that prevents a team with the most efficient power unit from also having the most efficient aerodynamic package.

The only inherent downside of carrying additional fuel is the mass penalty. There are no regulations limiting total fuel load, only the rate at which fuel may be consumed (fuel flow). Under the current regulations, the ICE is permitted to charge the ES, and as a result, the ICE can consumption fuel to generate electrical energy. However, the constraint on ICE-based energy harvesting is not fuel availability, but rather the operating conditions and opportunities presented by the circuit.

These opportunities are track-dependent and are governed by factors such as throttle demand, engine operating points, and energy management strategy. In simple terms, when the ICE is required to deliver higher mechanical power for acceleration, less surplus power is available to drive the MGU-K for battery charging (noting this is a high-level simplification).

Therefore, increasing fuel load does not directly translate into increased energy harvesting potential, as energy recovery is ultimately limited by deployment demands and available operating windows rather than total fuel mass. However, a more efficient ICE will definitively allow the car to start with a lower fuel load.

My original post was addressing the incorrect belief with many that somehow this ruleset makes ICE power / efficiency much more important than in previous regulations. That somehow regeneration amplifies the benefit. It does not. With similar strategies, a 1% ice benefit will result in a 1% benefit in electrical power. I.e. a 1% benefit of your total power. The same as it would have been with an ICE only powertrain.

I guess you missed the wink on carrying extra fuel.

Fair enough.