Idea to further boost fuel economy

[Milo]

I've never heard of this being done but I wonder if it will work?
You've heard of electric cars and bikes but what if they had a built in generator? This engine does not directly power the vehicle but instead runs at it's peak revs/power/efficiency to charge the batteries until full and only cuts in again when the levels run low.

I know because of the whole conversion to electricity and stuff it'd lower the efficiency but surely it'd still be pretty darn good?
Also a much smaller engine would be needed to power the vehicle as the acceleration is provided by the motors - a 250cc engine for a car version would surely be enough?

I've been thinking about this for ages and in a few years I'd like to build a concept - but I'd need the money, garage and knowhow first!

Any thoughts on this?

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Shaft drives rule.

[Ninja]

Thats generally how turbine powered cars run - not directly by the turbine, but by an electric motor taking power from a turbine powered dynamo . . . .
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James
4 wheels transport the Body ... 2 wheels transport the SOUL

[Mr C]

I think that the problem is probably battery technology and the fact that 100hp electric motor is quite a hefty chunk of copper wiring.

It would be too heavy (in a bike) for any appreciable power to weight ratio


is my first guess without really thinking about it and would have another cycle of losses into it so would actually be less fuel efficient


edit

also, since acceleration is generally governed by torque and high torque motors are even bigger and draw HUGE current so your wiring has to be mighty chunky as well
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187.3bhp = 201mph

[Kickstart]

Hi

Basically how diesel electric trains work, and there are hybrid cars around which use a similar system.

However there are problems. You would certainly need more than a 250cc engine. The electric motors weigh a ton (although you can play with the eletrics and also use them as brakes which generate power as you slow down). The batteries weigh a ton.

Also, how do you fancy sitting at traffic lights with an engine screaming away under the bonnet?

All the best

Keith
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[Mr C]

it's also the way ships are going

basically thumpy old diesels are not environmentally friendly or noise freindly any more so more ships are powered by turbines

the problem with turbines is that it's better to remove them to overhaul them than do it in the ship

so it would be better if they were mounted nearer the deck than the keel

the answer - a power station on the deck and electric thrusters for propulsion and steering

it's coming soon
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187.3bhp = 201mph

[Milo]

So not ideal for bikes then.
How about a few dynamo's on the tyres to power some electric motors and do away with the engine and battery's altogether? Just need a small run-start in the mornings and if you stop at the lights.
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Shaft drives rule.

[Mr C]

nope sorry

that's perpetual motion and it's not allowed

each dynamo will have horrendous losses

even if it's 90% efficient, it will still only converty 90% of the rolling energy into electricity

then if you assume the same of the motor then you only end up with 81% of the power you put in

it wouldn't go very far
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187.3bhp = 201mph

[Flip]

A better idea for fuel ecomony would be to steal fuel

[clemsta]

They make diesel trains like this, because if the wheels turned straight off the engine then the gearbox would be the size of a carrage. It would probably be too big for a bike though. Battery would need to be alot bigger, also you'd need a motor plus the engine. I think it would probably be pretty slow as well.

[Frost]

such things have been done in cars in the past, where the engine cuts out when its being inefficient and an eletric motor kicks in running off batteries charged off the engine.

in theory what you say could/would work. where by the engine premenantly runs at peak efficiency charging a batterie which then powers the wheels. however if the engine was not powerful enough then when the driving is inefficient(traffic) then battery power is going to drain as the motor is using more power than the engine will produce. similarly when the motor is running efficiently, the engine will be producing more power than neccicary.

Such a system could possibly be built and used in a car however as it uses petrol still, the improvement in efficinetcy would not be as high as if it were a pure electric car or a fuel cell car.

Such a design could not be implemented on a bike as the weight of batteries, generators and eletric motors would make the bike so heavy as to cancel out any increase in efficiency.

nice idea though

[mchaggis]

I personally prefer electrically driven supercharged smaller capacity engines. Get the same power as a 1.8 from a 1.0. No turbo lag, lower bsfc (brake specific fuel consumption), variable boost etc etc etc.. That or a compression ignition engine running on powdered charcoal. Though I'd rather use biomass for fuel when the petrol goes awol.

As far as using smaller engines for hybrid cars, you still have to produce the power, and still burn the same fuel. Though obviously anything which will let it burn at it's peak efficiency is better. Electric motors might be as efficient as 90%, but with 90% of 20-35% isn't an improvement.

Almost 5am isn't my best time for thinking about these things though.

[Milo]

[Milo]

Well darn it...someone's gone and done it.

I was at the Motor Show yesterday and there was a new Mini with 4 hub-centre motors and a 240cc twin cylinder generator - this was all that was enough to keep it juiced up...and it was 250BHP+ according to the specs.

Can't remember the company and can't find it on Google - did anyone else see it there?

Told you it would work! / / /
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Shaft drives rule.

[0ddball]

Look on the bright side, if you could have done it you'd have needed about £1m just to build the concept. It has more circuit boards then a branch of Dixons.

Bit of info on it here, actually 640bhp.

https://carscoop.blogspot.com/2006/07/electric-powered-mini-qed-concept-with.html

Though something doesn't seem quite right about it. All that energy from a tiny 250cc ICE as the primary source. I think there may be a few skeletons in the cupboards that they aren't mentioning.

[Zimbo]

There's a Dutch firm called Star Twin making a 1200cc TDi sportsbike, based on a modified VW Lupo TDi engine mated to an FJ1200 gearbox.
The bike weighs around 220kg, puts out around 120bhp and an eye watering 250 foot pounds of torque in performance trim(that's more than a Triumph Rocket 3, for comparison a Gixxer thou puts out about 80 foot pounds) and returns around 150mpg.

https://www.gizmag.co.uk/go/4273/1/



https://i71.photobucket.com/albums/i148/zimbo16/DSCF4200.jpg

[stinkwheel]

Hybrid bike has already been done. Uses electric power up to about 30mph then transferrs over to the engine. A claimed 180mpg. Sorry.

https://www.hybrid-vehicles.net/images/eCycle/ecycle-hybrid-motorcycle.jpg

https://www.hybrid-vehicles.net/ecycle-hybrid-motorcycles.htm

[instigator]

[Milo]

[Raffles_Gentleman Thug]

[Milo]

[Kickstart]

[Itchy]

[Kickstart]

Hi

Good point, and I think that is one of the reasons trains use diesel electric engines.

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[extreme3d]

[colin1]

id love to have a 'star twin' and run it on filtered chip oil
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colin1 is officially faster than god