[masklinn]

> Does it need to be able to run in all electric to be considered a hybrid?

Well I'd say so, using multiple power sources is what makes a hybrid vehicle hybrid. If it must always use the ICE, it just has an electric transmission rather than a mechanical one.

[msandford]

> If it must always use the ICE, it just has an electric transmission rather than a mechanical one.

I would respectfully disagree. When an engine is asked for WOT most of the time they throw fuel economy to the wind and give it max power bar none. You might spend 50% more fuel for 10% more power versus 90% throttle.

If you have a 3kWh battery bank then you can eliminate this really wasteful special case and use the batteries as very, very short term power source to get the vehicle up to speed quickly. 3kWh discharged in 3 minutes is 60kW which is an extra 50-75HP depending on your driveline efficiency. And then when you're not flooring it you can run the engine a bit harder and quickly recharge the battery bank for the next surge.

Just because you're not running off of batteries for an hour doesn't make it not a hybrid. If you use the batteries for even just 10-15 seconds in particularly fuel-wasteful engine conditions to eliminate them, that totally qualifies as hybrid.

[masklinn]

> Just because you're not running off of batteries for an hour doesn't make it not a hybrid. If you use the batteries for even just 10-15 seconds in particularly fuel-wasteful engine conditions to eliminate them, that totally qualifies as hybrid.

That means any KERS or regenerative braking[0] qualifies the machine it's a component of as a hybrid, it completely devaluates the word and makes it entirely meaningless.

[0] unless it stores back in the same place?

[zardo]

I'm an automotive engineer, if a system can recover kinetic energy and use it for propulsion, we call it a hybrid. KERS is absolutely a hybrid system, they are just optimized for power instead of energy.

The real pedantic question is does predictive cruise control count as a momentum hybrid.

[msandford]

If you have regenerative braking most of the time that's electric, so you've got a motor/generator and some kind of energy storage. To me hybrid means that you have a gas/electric hybrid drivetrain not that it runs off of batteries for an amount of time that you feel is long enough.

Good regenerative brakes probably have to be at least 50-100HP otherwise they don't offer very much braking effect. And that would mean that they can offer a substantial boost during acceleration too. And that can substantially alter the fuel economy of a vehicle.

Since you don't like my definition of hybrid, and you think it devalues the word (despite being completely in line with the Wikipedia definition) why don't you at least offer your definition. This isn't a conversation at the moment, just you shitting on things that you don't like and complaining.

https://en.wikipedia.org/wiki/Hybrid_vehicle

[masklinn]

> If you have regenerative braking most of the time that's electric

That's just a confirmation of my footnote not an answer to my question. Is an F1 with KERS or a truck with hydraulic regenerative braking a hybrid?

> not that it runs off of batteries for an amount of time that you feel is long enough.

That I agree with actually.

> Since you don't like my definition of hybrid, and you think it devalues the word (despite being completely in line with the Wikipedia definition) why don't you at least offer your definition.

That it can use its power sources independently.

[msandford]

> That it can use its power sources independently.

I would suspect that all hybrids can use their power sources independently, to some degree. But is that degree useful.

What you're calling a "hybrid" is really more of a "dual fuel" vehicle, not a hybrid. Because in your mind, if it can't run completely 100% off of EITHER power source at any one time, it's not a hybrid. But that's not how most of the world defines hybrid.