alternative tech - KERS for the road

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Mon 3 Sep 2012 23:30
alternative tech - KERS for the road - likerocks

I was wondering to myself today whilst stuck in traffic, not using any of the 140 turbocharged bhp available to me...

There is a definite trend for downsized petrol engines. But these seem to have a lot of the tech that gives diesels a bad name....turbos, dmfs, direct injection etc.

Then there are petrol / electric hybrids which carry a large weight penalty and I think time we show them not to be all that green once raw material sourcing for the battery is taken into account

Why doesn't anyone make a modestly petrol engined car, of (say) 80bhp with an in-parallel electric motor which provides transient (say) 50bhp power boost for just (say) 10-20 seconds at a time? On most journeys, a bit of sliproad acceleration or spooling up for an overtake is the only time one gets anywhere near full throttle.

To my mind, the electric motor would replace the starter, alternator, allow brakes to be smaller not to mention allowing a smaller overall engine & transmission. The weight penalty would surely not be too great. And instead of huge Lithium Ion cells under the seats weighing things down, the limited amount of electricity stored could be taken care of with smaller battery / flywheel / capacitors.

Are the amounts of electricity and storage technology not quite there yet to make this practical, or are there other reasons?

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Tue 4 Sep 2012 01:03
alternative tech - KERS for the road - bathtub tom

They're out there already. BIL bought a Volvo with stop-start technology that's got zero VED,

Apparently it's got an additional battery somewhere behind the (fragile plastic trim they call the ) bumper.

Let's hope they're more robust than the Lucas dynastart I had on my old bubble-car. Cost me a fortune every time the commutator segments lifted.

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Tue 4 Sep 2012 01:23
alternative tech - KERS for the road - unthrottled

Your theory is entirely correct. but consider this: How long does it take for a mains supply to charge your mobile phone battery? A 13A fuse can support 3 KW-sufficient to completely charge your phone battery in a couple of minutes, yet a full charge takes hours.

The reason is that fast charging/discharging of most major batteries drastically reduces the lifetime of the battery. Battery chemstry simply cannot support high output electric motors without a huge battery with many cells so that the voltage across each cell is sufficiently low.

Capacitors cannot store a sufficiently large amount of electrical energy, batteries cannot charge/discharge the energy at a sufficient rate. This is why I think the electric craze is just that-a craze based on a false premise.

Edited by unthrottled on 04/09/2012 at 01:30

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Tue 4 Sep 2012 02:34
alternative tech - KERS for the road - Carole4X4
I'm with unthrottled on this one re batteries.
In my hobby of r.c. Car racing we have batteries that can produce great bursts of power (lithium polymer batteries -lipo) but only in short bursts, the battery life would be greatly reduced to produce such power over a prolonged period. Also to prolong our battery life we are recommended to charge the cells at no more than 1c (I.e. a 5000amp battery to be charged at no more than 5 amps). Even at 1c charge the useful life of our batteries are no more than 300 charges.
Translate that to batteries required to drive a sufficient electric motor to propel something even as small as a supermini and it becomes economically unviable and rather challenging.
I also agree that electric powered vehicles may just be a dream and a stopgap to appease the green brigade until a more suitable and viable energy source is found.
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Tue 4 Sep 2012 02:56
alternative tech - KERS for the road - 1litregolfeater

I was watching that film last night, the one about Northern Soul where the boy gets on his moped and rides all the way from Stoke to Wigan. A moped will take you miles for very little outlay, but not in much comfort.

I've done the same myself. I think we all have. If we haven't. we ought to.

Cars are too big, too heavy and too fast. We're marketed at like a war of attrition but everybody thinks they're above it. We are hypnotised into believing our decisions are rational.

The cars get bigger, the engines more powerful, the gimmicks never stop. Air-Con? 4x4? Sat Nav? All made to render your expensive toy obsolete within 5 years.

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Tue 4 Sep 2012 11:51
alternative tech - KERS for the road - colinh

Toyota give an 8 years warranty on their hybrid battery, and it's basically carrying out a "KERS" type duty

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Tue 4 Sep 2012 12:06
alternative tech - KERS for the road - unthrottled

Loads of cars have a KERS type ISG, but any more than very gentle braking and the service brakes kick in. Better than nothing in stop-start work, but just extra weight on the motorway.

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Tue 4 Sep 2012 14:06
alternative tech - KERS for the road - Collos25

"Why doesn't anyone make a modestly petrol engined car, of (say) 80bhp with an in-parallel electric motor which provides transient (say) 50bhp power boost for just (say) 10-20 seconds at a time? On most journeys, a bit of sliproad acceleration or spooling up for an overtake is the only time one gets anywhere near full throttle"

They do its called a Toyota Prius and a more boring and complicated car you will have a long to find.

Having had one for all of two weeks it had to go before I lost my sanity.

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Tue 4 Sep 2012 18:53
alternative tech - KERS for the road - gordonbennet

What gives Collos, i noted that you had gained a Prius and was looking forward to some user input, blink of an eye and you're no longer a hybridee.

Daresay you're not short of a few bob, much like our leader and mods..;), so why did you get it, and why did you get rid of it, i'd be most interested if you would please.

Edited by gordonbennet on 04/09/2012 at 18:53

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Tue 4 Sep 2012 19:18
alternative tech - KERS for the road - Andy P

Friend of mine has just taken delivery of an Ampera. Took me out for a quick spin last week and I was quite impressed (for a Vauxhall). His current fuel consumption is above 130mpg (charged at home, then petrol engine recharge on the way home). Interior is a bit plasticky and I don't think it's worth what it costs, but probably the best option if you want to go "green" at the moment.

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Tue 4 Sep 2012 21:05
alternative tech - KERS for the road - likerocks

Collos - it was the Prius that inspired my rough-figure power output calculations but I just didn't see why it needs such a big battery with miles and miles of part or even full EV capability.

I now take on board what unthrottled said about battery size being a necessity of charge / dicharge rate as well as just overall capacity....

Shall I take it as read, then, that KERS components in F1 cars have a very limited operational life span?

I wonder how close we are to novel electricity storage tech?

Edited by likerocks on 04/09/2012 at 21:09

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Tue 4 Sep 2012 21:34
alternative tech - KERS for the road - unthrottled

Component longevity is a big concern on F1 cars-they have to last nearly 1000 miles! Completely different kettle of fish to road car longevity. Even with F1 levels of care, the first season of KERS was very rocky.

I think the OEMs might be going down the wrong path with KERS. I'm sketching out an alternative version. Hey, might make me my first (long overdue) million!

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Tue 4 Sep 2012 20:27
alternative tech - KERS for the road - coopshere
"Cars are too big, too heavy and too fast. We're marketed at like a war of attrition but everybody thinks they're above it. We are hypnotised into believing our decisions are rational.

The cars get bigger, the engines more powerful, the gimmicks never stop. Air-Con? 4x4? Sat Nav? All made to render your expensive toy obsolete within 5 years."

Ah the power of advertising and ego, an excellent description of modern mans desires 1litergolfeater.

Edited by coopshere on 04/09/2012 at 20:28

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Tue 4 Sep 2012 21:27
alternative tech - KERS for the road - injection doc

Having just experinced a friend with a Nissan leaf Breaking down, recovery people didnt know what to do with it or how to recover it and trying to find a dealer interested in dealing with it well that was quiet enlightning. It had to be recovered miles away !

now that doesnt bode well.

Cars with kers or electric batteries dont get my vote yet ! Think it will take many years

" All made to render your expensive toy obsolete within 5 years." definatley.

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Tue 4 Sep 2012 21:48
alternative tech - KERS for the road - Collos25

"Daresay you're not short of a few bob, much like our leader and mods..;), so why did you get it, and why did you get rid of it, i'd be most interested if you would please".

We are all entitled to make mistakes it looked a good deal at the time but it turned out otherwise in my opinion the cars are a complete waste of money hindsight is a wonderfull thing.

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Tue 4 Sep 2012 22:08
alternative tech - KERS for the road - gordonbennet

Thanks Collos, if you'd care to expand on that i'd be grateful.

When my LPG'd ancient MB eventually dies i shall either get another half decent engined petrol car and LPG convert it, or i have been drawn towards Lexus' hybrids in the shape of the GS450h or RX400h.

I would be interested in what turned you against the Prius so quickly, wouldn't want to make the same mistake.

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Wed 5 Sep 2012 15:38
alternative tech - KERS for the road - Collos25

Overcomplicated controls for all functions especially the sat nav and heater ,underpowered although I rarely go over 120kmh ,poor bland trim,very similar in build to a 1972 Datsun 180,not very economical beaten easily by 1.6hdi engine on all fronts,extremely complicated drive system and dangerous nobody can hear the car when on battery,handling is a joke even to an old get like me,As I said we are all allowed to make mistakes and this was my crowning glory. Don't let me put you off try one but make sure you test drive it in all conditions I have a friend with a new lexus hybrid thats not quite as bad as the prius but it only achieves around 28mpg .

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Wed 5 Sep 2012 16:34
alternative tech - KERS for the road - madf

I drove a Prius and I found it simple to drive: (It was a Mark2 not a Mark3). Averaged 50 ish. Got in, was shown controls, drove.Agree about the handling.

The drive system may be complex but 300k miles is quite common..

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Wed 5 Sep 2012 18:22
alternative tech - KERS for the road - gordonbennet

Thanks Collos, like Madf i found the car simple to drive, simply shove it gear and drive as if a normal torque converter auto, i'm used to foot operated parking brakes anyway.

Toyota's satnav is a joke, a bad one, the Hilux we had it came as standard fitment, instruction book for satnav was as thick as that for the rest of the vehicle, though once eventually programmed did work very well.

Handling, presume you mean grip?. I'm not convinced by these eco tyres, for the slight loss of economy involved i'd rather put something on with a bit of bite.

Again thanks for coming back.

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