DIY Electric Car Forums banner

1 - 20 of 22 Posts

·
Registered
Joined
·
926 Posts
Discussion Starter #1
This might appear as a stupid question, but I'd love to get everyone's take on this.

I think it was on the EV Cast, but I heard someone announce a while back that a Toyota Prius isn't technically a hybrid. He went on to say a hybrid must have equal and optional usage of both the electric and ICE components.

If this is true, then the Prius is just a regular gasoline car with electric assist - not a parallel hybrid. Also, it would mean the new Chevy Volt is not an EREV (extended range electric vehicle) but just a regular series hybrid.

Ive looked around for an engineer's definition of hybrid vehicles, but I only get rather basic descriptions. It's something that's been in my head for some time.

I need a hobby. Maybe one involving cars and electric motors... That'd work.
 

·
Admin: 'one of many'
Joined
·
4,838 Posts
I think a hybrid is just an offspring from two completely different parents.

In automotive terms it should mean the cross between an electric car and an ICE car. That would mean that it would have both ICE and Electric drive systems in any configuration.
The configuration could then be further defined by explanation but that would not change the original definition of the vehicle being a hybrid in general terms.
 

·
Registered
Joined
·
780 Posts
Hi. To me, the term "hybrid" is a marketing buzz word to be applied when convenient to be manufacturer. For example, the Ford Volt is a hybrid. It uses both ICE and electric motors to propel itself down the road. But don't tell that to Ford! They insist it's an electric... but with gasoline.. you know, like your blender... that uses electricity and... gasoline.. too. The Prius is a hybrid. Your EV towing a genset in the back is a hybrid.

All of the parallel, series, parallel/series terms are smoke screens trying to distant themselves from being called what they are: gas guzzlers.

I'd say that if your electric car has a gasoline tank, a hydrogen cell or a "Mr. Fusion" reactor that runs on banana peels, it's a hybrid. If you charge your batteries somewhere and consume that power while driving, it's an electric.

JR
 

·
Registered
Joined
·
12 Posts
From an industry perspective, regardless of marketing BS, a hybrid is a conventional petrol powered car that captures "waste" energy to charge a battery pack and uses it to power the electric motor that provides supplementary power/torque to reduce fuel consumption and emissions.


As an interim technology the reason they exist at all is simply because the average person doesn't like change and wants cars that works the way they're used to, in other words that you can hop in and go without waiting for it to charge, that can be fuelled in a matter of minutes from any petrol station and that doesn't have a charge range limit.


It's not just the limitations or high price of EV's that keep ordinary motorists away, it's fact that you have to plug it in and wait for it to charge and whilst you may think that's just something to work around the average motorist doesn't want anything that requires them to do anything different to their normal routine.


For the same reason, with the technologies as they currently stand, it looks like hydrogen fuel cell will win out as the next gen car technology, in spite of the energy required to "make" hydrogen and the fact that a fuel cell is more or less a large bomb, simply because you fill a fuel cell car up at a fuel station in the same way you do with a petrol/diesel car, so no waiting for it to charge and no range limits.
 

·
Registered
Joined
·
926 Posts
Discussion Starter #5
it looks like hydrogen fuel cell will win out as the next gen car technology, in spite of the energy required to "make" hydrogen and the fact that a fuel cell is more or less a large bomb, simply because you fill a fuel cell car up at a fuel station in the same way you do with a petrol/diesel car, so no waiting for it to charge and no range limits.
Interesting that you should say that. I used to think that too until recently. For whatever reason the car makers are changing their game. Perhaps they're realising that hydrogen is the fuel of the far (not immediate) future , with electrics & hybrids being the better short term bet.
Even Honda and BMW (the big hydrogen players) have gone quiet on their hydrogen cars, building electric car prototypes instead.
 

·
Registered
Joined
·
4,007 Posts
I vote for woodsmith's answer. If you're running both, you're a hybrid. Doesn't matter if you use one to drive and the other to make energy, or they both share, it's still a hybrid.

it would mean the new Chevy Volt is not an EREV (extended range electric vehicle) but just a regular series hybrid.
The only reason the Volt is not called a hybrid by everyone, is because GM is afraid of it, and has shunned it, so they made up the EREV thing. If people start calling the Volt a hybrid (media has recently) it has to compete with the Prius, and it can't.

If Toyota had released the plug-in prius in the US years ago instead of saying "the market won't support it", the Volt could never have been made without costing half as much or getting double the MPG.

2 greedy companies getting what they deserve...
 

·
Registered
Joined
·
12 Posts
Interesting that you should say that. I used to think that too until recently. For whatever reason the car makers are changing their game. Perhaps they're realising that hydrogen is the fuel of the far (not immediate) future , with electrics & hybrids being the better short term bet.
Even Honda and BMW (the big hydrogen players) have gone quiet on their hydrogen cars, building electric car prototypes instead.
You're right but (as things stand) hybrids and electrics are interim technologies, not the future of motoring. Fuel cell technology is better developed than you may think, remember Honda have a hydrogen fuel call car (the FCX Clarity) you can lease right now.. as long as you live in California. Development is being held back far more by the problems of generating and safely storing hydrogen, especially generating it which takes so much energy you may as well power a bunch of electric cars with it!
Then again bioethanol was going to be the future for all cars, until someone figured out there isn't enough crop space in the word to maintain a world fuel supply! :D
So by the time someone figures out how to produce hydrogen cheaply anything could happen, it's always possible one the various "synthetic petrol" projects will simply get there first? Bioethanol is still the technology super car manufacturers are betting on but they represent a tiny sector of the market. :)
 

·
Registered
Joined
·
1,296 Posts
For my two bit.

The term 'hybrid' applies to plants, animals, etc.

Just like a hybrid rose... or a donkey... etc.

Different types of hybridization will have different effects ... good or bad.

In vehicle terms ... it might mean better MPG ... it might mean the same MPG but more kw of power ... or no change to power or MPG, but something else ... or any number of other effects... or no effects at all.

The abilities / effects of hybridization are secondary to the actual hybridization itself.

I personally view efforts at terms like , mild-hybrid, and full-hybrid ... to be nearly useless , almost counter productive ... I think it is more instructive to examine the actual design itself ... and to be honest with the pros , cons, different abilities, etc.
 

·
Registered
Joined
·
12 Posts
For my two bit.

The term 'hybrid' applies to plants, animals, etc.

Just like a hybrid rose... or a donkey... etc.

Different types of hybridization will have different effects ... good or bad.

In vehicle terms ... it might mean better MPG ... it might mean the same MPG but more kw of power ... or no change to power or MPG, but something else ... or any number of other effects... or no effects at all.

The abilities / effects of hybridization are secondary to the actual hybridization itself.

I personally view efforts at terms like , mild-hybrid, and full-hybrid ... to be nearly useless , almost counter productive ... I think it is more instructive to examine the actual design itself ... and to be honest with the pros , cons, different abilities, etc.
You're quite right obviously, the term hybrid simply means distinct things successfully combined, for good or bad. Porsche for example recently showcased a "hybrid" that uses a flywheel accumulator and hub motors to use regenerative energy as a boost device, but the point is (& I think this is what KiwiEV was getting at?) is that production hybrids are sold as being a car that can be used as a conventional petrol powered car or an electric vehicle and automatically switching between the two, usually suggesting you won't be producing any carbon in urban driving and that's simply not true.


In any production hybrid I've come across so far the electric drive system is a supplementary technology, not a system for alternative use. I currently drive a 2010 Honda Insight and whilst it will switch to "EV Mode" for half a mile or so (under ideal conditions) I can't pick and chose if I want to use it as a petrol car or an electric car and even when it switches automatically it's only for short distances when the battery pack has enough charge & the road is level or on a downward incline, which is not what hybrid manufacturers generally seem to infer. The electric motor is mostly used to supplement the torque missing from it's small petrol engine (& as a flywheel dynamo obviously.) The current Toyota Prius can be switched to "EV Mode" but at a maximum of 31 mph and for a maximum of 1.2 miles which is, let's be honest here, a gimmick that allows them to technically call it a car that can be used as either petrol or electric but not in a practical or regularly useful way.


Cars like the Insight, the Prius and the Ford US Fusion hybrid (not to be confused with the Ford Europe Fusion which is an entirely different car) will reduce carbon emissions in real use by capturing and using waste energy but won't allow you to drive from one side of, for example Nottingham UK where I live, to the other on electric only. On the other hand by buying a new car you've already done more environmental damage than you'll prevent because building a new car is hugely environmentally damaging and that for me is why the idea of taking an old car and converting it to an EV seems like such a good idea. :)
 

·
Admin: 'one of many'
Joined
·
4,838 Posts
That's one of the problems of buying a car from a mass manufacturer, you don't often get what you really want as they are trying to satisfy a much larger market and more importanty to them at least, maintain or increase their market share.

If you want a hybid that does exacly what you want then it will be a lot of shopping around in the hope that there is one or you 'DIY' one.

One of the problems of a 'hybrid' EV from my viewpoint is that it's pure electric range and performance can be greatly improved by removing the ICE and associated components. It can then be improved further by adding more batteries where the ICE used to be.
 

·
Registered
Joined
·
12 Posts
One of the problems of a 'hybrid' EV from my viewpoint is that it's pure electric range and performance can be greatly improved by removing the ICE and associated components. It can then be improved further by adding more batteries where the ICE used to be.
That's a really interesting point. I've been looking at it from the other direction, I don't count the Chevy Volt as a "proper" hybrid in the industry's sense of the term, as a product type, because a: you have to plug it in and b: the weight of all those extra batteries makes petrol consumption pretty poor.
Looking at it as the conventional components hampering electric performance rather than the other way around actually makes a lot of sense. If I start out with say a 7 - 8 year old Prius, strip the petrol related stuff out and replace it with batteries, a controller and a charging system it'll shortcut development considerably over building an EV from scratch?


Hmm.. I'll have to have a think about that. :)
 

·
Registered
Joined
·
143 Posts
I tend to think of it as a vehicle that has both an engine of some sort + another form of propulsion. I intentionally did not say an electric motor because there are hydraulic hybrids being produced {at least as "demonstration" projects}. The bottom line for me is, does the "other than engine" part of the equation contribute to the vehicles motivation.

I would not include GM's previous "mild hybrid" twins as a hybrid, because all the recaptured power did was charge the automatic stop-start feature. It made no contribution to moving the car. {I bought a 2008 Malibu Hybrid new :( and traded it off at 9 months old because of its lousy fuel economy.}
 

·
Registered
Joined
·
4,007 Posts
I don't count the Chevy Volt as a "proper" hybrid in the industry's sense of the term, as a product type, because a: you have to plug it in and b: the weight of all those extra batteries makes petrol consumption pretty poor
The Volt doesn't need to be plugged in any more than a plug-in prius does. You can drive it forever on just gas. It's a hybrid because it CAN take electricity too.

The weight thing goes the other way too, if you take an electric car, and add an ICE to charge the batteries, you won't get the same wh\mile due to the added engine + gas tank, so when you need the range it's worth it, and when you don't it's dead weight.

If I start out with say a 7 - 8 year old Prius, strip the petrol related stuff out and replace it with batteries, a controller and a charging system it'll shortcut development considerably over building an EV from scratch?
Most hybrids would be pretty tough to convert efficiently due to the electronics/complicated transmissions that are used to combine to inputs. That's why old donors are so easy, you just replace all the old with all new, with no waste left. Only a true series hybrid (or EREV as the Volt claims to be, but isn't as the ICE drives the wheels over 70mph) could be converted without extra crap left behind.
 

·
Registered
Joined
·
320 Posts
To me hybridisation is the bringing together of two (or more) distinctly different systems in such a way as to exploit most of the advantages of both systems while avoiding most of the disadvantages. This way the whole is greater than the sum of its parts in terms of the value derived from the hybrid.

As to whether or not the Prius is a true hybrid it would depend on whether or not you were talking about a hybrid of energy sources or motive power. But there is two distinctly different propulsion systems in the car hence to me it is a hybrid even if weighted too heavily towards petrol for my liking.

In a Petrol/Electric hybrid (such as the Prius) the ambition of adding the electric system to a petrol car is to improve the performance of that petrol car which in most cases means improving fuel efficiency and in less cases quicker acceleration among other benefits. The key disadvantage being mitigated is its poor energy efficiency.

In an Electric/Petrol hybrid (such as the Volt) the ambition of adding the Petrol system to the electric car is to improve the range of the electric car and allow rapid replenishment of energy storage (not necessarily fuel efficiency in charge sustaining mode). The Volt is a similar sized vehicle to the Cruze Eco. I think they might both be based on the same platform. The Cruze Eco will do 42 MPG hwy and the Volt 40 MPG hwy! In the city where the Volt can take advantage of idle stop and regenerative braking it gains a significant edge of 35 MPG versus 28 MPG for the Eco. Compare this to a Prius which I think is a bigger car. It will do 48 MPG hwy and a whopping 51 MPG city. Stop and go is where it really shines. The key disadvantage being avoided in the Volt is poor range and replenishing time.

In the petrol car the source of motive power (the engine) is heavy and the energy storage (gas tank) is light. In the electric car the source of motive power (the motor) is light (or at least it can be) and the energy storage (the battery) is heavy. To put two full performance systems into one car the added weight would cancel out the advantage. The optimisation is always going to be with a smallish battery to minimise the weight of the electrical system and a smallish ICE to minimise the weight of that system. The long range will be furnished by the light weight energy storage and the performance will be augmented by the light weight motive power source. The current bottle neck preventing a more powerful electrical systems and hence less powerful ICE systems is the power that can safely and sustainably be drawn from the small batteries. As the batteries power density improves I expect hybrids to come out with more powerful electrical systems and smaller ICE’s and much improved fuel efficiency.
 

·
Registered
Joined
·
1,296 Posts
the point is (& I think this is what KiwiEV was getting at?) is that production hybrids are sold as being a car that can be used as a conventional petrol powered car or an electric vehicle and automatically switching between the two,
I agree that seems to be the focus for a fair number of people.

I personally do not like that focus / perspective ... I just think it goes down a counterproductive path.

I still think it is better to honestly examine a design for it's pros and cons for a given desired context.

An EV-Mode is not without it's down sides ... I think putting an EV-Mode on a pedestal , is counter productive... being honest about how it helps and how it hurts is more useful.

If you have a small enough EV-Mode Range ... your on board electrical energy is more efficiently spent load leveling the ICE to keep it operating at it's best efficiency ... and not to burn it all up in an extremely short EV-Mode, and then have to use the ICE to deal with all power fluctuations... as doing so would force the ICE into far less efficient modes of operation.

If you have enough EV-Mode Range to not need to use a range extender like an ICE ... than the ICE is dead weight... for all such full EV-Mode trips... and it would be more efficient not to have that dead ICE weight.

And if the context is just right ... where you have enough electrical energy storage to keep the ICE at it's peak efficiency all the time ... and still have more ... but still not enough to be in pure EV-Mode for 100% of the trip ... it is in that tiny window of context it is actually useful to have both an ICE and use a EV-Mode.

But a Hybrid does not have to be a HEV ... and there are other methods of making a hybrid and having pros and cons to them.

I think the further electrification of the transportation system is inevitable ... there are too many benefits ... to few disadvantages ... and I think the first stage of HEVs was just the least expensive / easiest way for companies and consumers to tip toe into it ... but over time ... HEVs will give way to PHEV ... which will give way to BEVs... even if I think ICEs will still be in vehicles for many decades yet to come.
 

·
Registered
Joined
·
12 Posts
The Volt doesn't need to be plugged in any more than a plug-in prius does. You can drive it forever on just gas. It's a hybrid because it CAN take electricity too.

That would just make it a very heavy petrol car? :\
Honda kicked off the hybrid market with the original Insight in 1999. A big part of the original brief was that is should use regenerative energy to reduce fuel consumption and emissions because the market in general didn't want cars you have to plug in and that's become the basic standard for "Hybrids" as a product type as a result.




The weight thing goes the other way too, if you take an electric car, and add an ICE to charge the batteries, you won't get the same wh\mile due to the added engine + gas tank, so when you need the range it's worth it, and when you don't it's dead weight.

Surely adding a fuel burning motor to an electric car would completely defeat the point of buying/building a zero emissions vehicle in the first place? An integral part of buying/building a zero emissions vehicle is accepting it's limitations, so ZEV's are usually a 2nd vehicle, something just for short journeys. Otherwise you just end up back at a petrol car that's emissions are increased by the weight of the electric components and even worse if you're using the fuel burning motor to power the electric drive system as you suggest it'll be even less efficient! I know that's how diesel electric trains work but they work with large scale components that provide the massive, consistent torque you need to shift a fully laden train. (Unless you're thinking along the lines of a self-contained auxiliary outboard on a boat? If all else fails at least it'll get you to safety? :\ )

Most hybrids would be pretty tough to convert efficiently due to the electronics/complicated transmissions that are used to combine to inputs. That's why old donors are so easy, you just replace all the old with all new, with no waste left. Only a true series hybrid (or EREV as the Volt claims to be, but isn't as the ICE drives the wheels over 70mph) could be converted without extra crap left behind.
CVT's aren't hard to work with but I see what your getting at (in your own patronising and aggressive way). So back to looking for a cheap, light weight monocoque and efficient motors. :)
 

·
Registered
Joined
·
12 Posts
So I guess we can all come to a consensus on the answer to KiwiEV's original question then can't we? It seems from what's been covered in this thread that there isn't really a definition of a "hybrid" car. It's a car that uses and extra drive system of some kind for some reason but what, how and why isn't really standardised, so manufacturers come up with their own marketing terms like "full hybrid", "EREV" Etc.

Would that about cover it for everyone? :)


This is just my opinion so let's not get in to a big argument about it, but with the lack of standardisation I still like the current Insight as a solution (and not just because I don't have to pay for it! :p) Honda have focused on driver psychology and encouraging economical (& therefor reduced emissions) driving. The most flawed and least controlled element of the car is the person driving it, so literally making economical driving in to a video game is a work of genius, especially for lead-footed oafs like me!
In spite of taking it to the test track a couple of times I've got 4 leaves on all 5 plants and I'm working toward the 5 flowers. The eco-assist computer gave me a 4 leafed eco plant in a laurel wreath when I got the second line of leaves and it genuinely seemed like an achievement! :)
 

·
Administrator
Joined
·
6,157 Posts
Hi Guys
I think John had the right of it

n a Petrol/Electric hybrid (such as the Prius) the ambition of adding the electric system to a petrol car is to improve the performance of that petrol car which in most cases means improving fuel efficiency and in less cases quicker acceleration among other benefits. The key disadvantage being mitigated is its poor energy efficiency.

In an Electric/Petrol hybrid (such as the Volt) the ambition of adding the Petrol system to the electric car is to improve the range of the electric car and allow rapid replenishment of energy storage (not necessarily fuel efficiency in charge sustaining mode).


The difference is a Petrol/electric or an Electric/petrol

Different animals - both hybrids! - also we have car/boat hybrids, car/plane hybrids

The car/boat hybrids can be like the Sealegs
http://www.sealegs.com/

or like the Amphicar
http://en.wikipedia.org/wiki/Amphicar
 

·
Admin: 'one of many'
Joined
·
4,838 Posts
Well obviously!?! I don't see your point though? =\
You understand don't you that not everyone who isn't you is 5 years old or a complete idiot right? If you read back what you've written and it sounds both unbelievably patronising and completely irrelevant, keep it to yourself... unless you're trying to kick off a flame war? Godwin's law on standby... :mad:
Can we avoid this type of post please.

I saw nothing patronising or flaming there and the level of discussion was no different to any other post made so far on this thread.

If you disagree with what has been posted then accept that it is a point for discussion not name calling or bullying. Everyone here has a right to their view if it is relevent to the thread and forum.

Please check the terms and conditions of posting on this forum if there is any doubt.

Admin
 

·
Registered
Joined
·
12 Posts
Can we avoid this type of post please.

I saw nothing patronising or flaming there and the level of discussion was no different to any other post made so far on this thread.

If you disagree with what has been posted then accept that it is a point for discussion not name calling or bullying. Everyone here has a right to their view if it is relevent to the thread and forum.

Please check the terms and conditions of posting on this forum if there is any doubt.

Admin
Woodsmith is absolutely right, I should have been more diplomatic. My apologies to all. :)
 
1 - 20 of 22 Posts
Top