When is a hybrid a hybrid?

[Piwoslaw]

What exactly is a hybrid?
(1) Is it any vehicle that has more than one type of engine?
(2) Is it any vehicle that gets its power from more than one source?

Many cars sold as hybrids do have two types of engines, internal combustion and electric, but most of them (except for plug-ins) get their power only from one source anyway - gas. On the other hand, I've seen normal ICE cars branded as hybrids only b/c they are dual fuelled - CNG/LPG plus normal gas.
Vovlo, BMW, VW, etc., say the eco versions of certain models have regenerative braking, which in this case means they have a beefed up battery and the alternator switches off when accelerating and on while engine braking. Is this really regen? And is it enough to slap a 'Hybrid' sticker on?

What about the following example: Imagine a totally ecomodded ride. Everything that normally hangs on the engine is now electric - water pump, oil pump, A/C, vacuum pump (diesels), maybe even the high pressure fuel pump (commonrail) or electronically actuated valves. It has a plug-in block heater, transmission heater, fuel heater, and cabin heater. The battery is charged at home when needed, other than that by roof PV, exhaust TEG, small alternator that kicks in when engine braking. Is this car a hybrid? The lack of all accessories now allows the engine to run much more efficiently (I'm guessing they are responsible for up to 30% of the power and/or fuel consumption). With a bit of luck, the electrical side won't need charging at home, so it's just a super efficient ICE car. But if we charge do it at home, then it's a hybrid?

[cfg83]

Piwoslaw -

Is there a place where your example would fit into this Wiki? :

Hybrid vehicle - Wikipedia, the free encyclopedia

They mention the dual-fuel example and state that it is more properly a "dual mode" vehicle.

PS - The Wiki has a discussion section, so maybe the question could be generalized outside of Ecomodder.

CarloSW2

[RobertSmalls]

Last night, my father and I were going to the store in the Insight, and I told him about the grid charger I just installed. He was a little disappointed to hear these cars didn't come with chargers from the factory. He then asked how far I could go without using gas. Well, I can't really; I don't have the software for it.

So then he said "Well, it's not really a hybrid, then, is it?". Hmm.

I've been using the definition: if there are more than one sources of motive force, it's a hybrid. Mine is a mild hybrid because these two sources of propulsion can't be used independently.

Before I installed the grid charger, my approach was to use enough regen to keep the 12V battery charged and run the engine stop/start function. I very seldom used assist. Even if the car didn't have electric assist, I would have been very happily sipping fuel, but it would not have been a hybrid.

But a stock Insight is a hybrid. And now mine has a plug to provide energy for motive force. Can it be called a PHEV, even though it doesn't have an EV mode yet?

[jamesqf]

Originally Posted by RobertSmalls

Can it be called a PHEV, even though it doesn't have an EV mode yet?

Whyever not? The point is to reduce gasoline consumption, not to make some academic point about having a pure EV mode. Just as practical engineering, Honda created a more fuel-efficient and far more driveable car by NOT having that EV mode.

But to the larger question, I think "hybrid" has to mean two (or more) propulsion systems. That's why diesel-electric locomotives, for instance, aren't hybrids: because the electric part only acts as a transmission.

[Piwoslaw]

Originally Posted by jamesqf

But to the larger question, I think "hybrid" has to mean two (or more) propulsion systems. That's why diesel-electric locomotives, for instance, aren't hybrids: because the electric part only acts as a transmission.

That is what is called a "series hybrid".

[jamesqf]

Originally Posted by Piwoslaw

That is what is called a "series hybrid".

No, it's not. You could make it in a hybrid quite easily, by adding some kind of energy storage (like batteries or a high-speed flywheel) to provide power to the electric motors, but a standard diesel-electric locomotive is no more a hybrid than a car with an automatic transmission is a hydraulic hybrid.

[user removed]

Fairly sure a diesel electric train is driven only by electric motors, because of reliability issues with a mechanical transmission and that much power and load.

My understanding is a hybrid can apply power from two different sources, and recover energy normally lost as friction in braking.

Most everything else is not specifically a hybrid.

Something not included in a hybrid description, that should be included, is the ability to pulse and glide the IC (or other primary fuel consuming power source) engine while maintaining a constant vehicle speed. This can be done with capacitive, repetative, non degrading, but highly efficient short term energy storage.

regards
Mech

[Piwoslaw]

Originally Posted by jamesqf

No, it's not. You could make it in a hybrid quite easily, by adding some kind of energy storage (like batteries or a high-speed flywheel) to provide power to the electric motors, but a standard diesel-electric locomotive is no more a hybrid than a car with an automatic transmission is a hydraulic hybrid.

True. I forgot about the batteries.
And it's a shame that trains don't have a means to store braking energy. Of course, I mean commuter trains and such, not long distance freight trains.

[Clev]

Originally Posted by Piwoslaw

True. I forgot about the batteries.
And it's a shame that trains don't have a means to store braking energy. Of course, I mean commuter trains and such, not long distance freight trains.

That drives me crazy. The local commuter service (Metrolink) has 12 stops between San Bernardino and Los Angeles (averaging about 5 miles between stops.) At every stop, they accelerate full-bore to track speed, and then when coming into the next station, apply full dynamic braking (turning useful momentum into electricity, and then wasted heat.) Meanwhile, there's a head-end power unit that's continuously burning diesel to heat, cool and light the passenger cars.

[Arragonis]

Originally Posted by Piwoslaw

True. I forgot about the batteries.
And it's a shame that trains don't have a means to store braking energy. Of course, I mean commuter trains and such, not long distance freight trains.

Some do I think. Leyland (the bus and truck people, not the clunky cars built by unionised militant workers) used a few different systems to generate energy from braking on buses, and later on their (unsuccessful) bus to train conversions.

One of them definitely used a compressed air reservoir of some kind. The pressure would be built up under braking then released to give the bus a 'push' when it started up to save fuel. Another system used a flywheel which would be spun up under braking and then used to power an electrical 'assist' on restart.

A similar system was developed by a german tuner in the early 80s to try and remove turbo lag at the time when turbos did nothing below 4000 rpm. The system bled some pressure from the wastegate into a chamber and then released it when the pedal was floored at lower engine speed. It would be enough to get the engine to the point where the turbo could take over. It didn't work in the real world of course, and they went on to use autoboxes to 'keep the engine spinning fast enough for the turbo'. Kind of like developing a super efficient hair dryer by inventing dry water.