Posted by Lord Gow333, Dirk Benedict's n on June 7, 2009, 2:27 am
> Lord Gow333, Dirk Benedict's newest fan! wrote:
>>
>>>
>>>> What would supply the energy to compress the air and why would we not
>>>> just
>>>> run that energy source a directlly as possible to avoid more energy
>>>> losses
>>>> in an inefficient storage system?
>>>
>>> The goal/advantage would be to pressurize the air so
>>> the its energy density would be greater than the
>>> fuel source that it replace. When this is accomplished
>>> one can achieve the ultimate reward - a high density
>>> energy source coupled with an extremely efficient,
>>> simple and reliable engine/motor . One of the barriers to
>>> making a EV - is that while electric motors are simplier
>>> and more efficient than than gasoline/diesel engines
>>> - the energy density of the best EV fuel cells are about
>>> 1/3 to that of a petrol based one. So any efficiency
>>> gained from having a lighter more efficient engine/motor
>>> is lost because the increase weight of the energy source.
>>> By changing engine performance and lowering the
>>> overall vehicle mass a conventional diesel/gas cars to
>>> get between 60 to 100 mpg - yes - they go a bit slower
>>> ( 0-60 mph in 15 seconds) they can not go as
>>> fast maybe ( top out at 85 mph ) - but they get
>>> 60 to 100 mpg. So where do they exist? Well
>>> you have to go to the Europe or Japan....
>>>
>>> here are two examples that I know of.
>>>
>>> 2005-2009 Toyota Aygo (Japan/UK/Europe) - a conventional 4 door sedan
>>> using a 3 cylinder diesel, about 65 mpg
>>> ( sister cars = Peugeot 107 and Citroën C1 )
>>> see http://en.wikipedia.org/wiki/Toyota_Aygo
>>>
>>> 2010 Axon hatchback (UK) - a 2 seater hatchback, carbon fiber chassis,
>>> gasoline engine, claimed 100 mpg
>>> ( btw this vehicle is an entry into the Automotive X-Prize Contest
>>> for best most practical commuter car)
>>> see http://www.axonautomotive.com/cars.html
>>>
>>>
>>> Jeromy Clarkson of BBC's Top Gear ( a UK auto review TV show)
>>> criticizes
>>> electric vehicles, HeVs, and PHEV and because of the high cost and
>>> low energy density of batteries ( which means extra weight and lower
>>> range)
>>> He prefers using either a conventional diesel or gasoline engine to
>>> power a
>>> vehicle.
>>>
>>> ----------
>>>
>>> This comes as a bit of surprise. I would think the limited range of
>>> EV's would not be much of a problem in the UK. How often do Britains
>>> drive more than a hundred km or so? Or is the price of electric versus
>>> high mpg just too much.
>>
>> I think Clarkson's argument was that hauling around all that extra weight
>> in the end burns up more energy than running a straight gas/diesel
>> engine. Motors have a different torque curve than engines so it's not
>> that cut and dry, but still something to ponder.
>>
>>> One of the EV's shortcomings in the US market is the longer distances
>>> that Americans want in their vehicles.
>>
>> Not to mention the fact that half of us drive around in snow for half the
>> year.
>>
>> A local talk show host, who drives a Hummer H2, cracked after the first
>> serious snowfall the one year "Hey, all you hybrid drivers... how's that
>> working out for you? Getting thru the snow okay with ALL THAT POWER?".
>>
>> On a more serious note, a local car Q&A guy told of driving an electric
>> car to a nearby town (about 30 miles, fairly hilly). The trip there was
>> nice, sunny weather, car zipped right along. Then they headed back. It
>> started raining, wipers on. It got cold, heater on. It got dark,
>> headlights on. Batteries drained, car slowed, and they barely made it
>> back.
>>
>> Hybrid or even electric works fine in Cali or Florida. WNYers need petro
>> engines, and often four wheel drive.
>>
>> LG
> Oh bullshit, any front wheel drive will take you just about anywhere all
> winter.
Still a petro engine.
LG
--
"Keep it simple. If it takes a genius to understand it, it will never work."
- Clarence Leonard "Kelly" Johnson
Posted by Richard W. on June 6, 2009, 4:48 pm
>>
>>> What would supply the energy to compress the air and why would we not
>>> just
>>> run that energy source a directlly as possible to avoid more energy
>>> losses
>>> in an inefficient storage system?
>>
>> The goal/advantage would be to pressurize the air so
>> the its energy density would be greater than the
>> fuel source that it replace. When this is accomplished
>> one can achieve the ultimate reward - a high density
>> energy source coupled with an extremely efficient,
>> simple and reliable engine/motor . One of the barriers to
>> making a EV - is that while electric motors are simplier
>> and more efficient than than gasoline/diesel engines
>> - the energy density of the best EV fuel cells are about
>> 1/3 to that of a petrol based one. So any efficiency
>> gained from having a lighter more efficient engine/motor
>> is lost because the increase weight of the energy source.
>> By changing engine performance and lowering the
>> overall vehicle mass a conventional diesel/gas cars to
>> get between 60 to 100 mpg - yes - they go a bit slower
>> ( 0-60 mph in 15 seconds) they can not go as
>> fast maybe ( top out at 85 mph ) - but they get
>> 60 to 100 mpg. So where do they exist? Well
>> you have to go to the Europe or Japan....
>>
>> here are two examples that I know of.
>>
>> 2005-2009 Toyota Aygo (Japan/UK/Europe) - a conventional 4 door sedan
>> using a 3 cylinder diesel, about 65 mpg
>> ( sister cars = Peugeot 107 and Citroën C1 )
>> see http://en.wikipedia.org/wiki/Toyota_Aygo
>>
>> 2010 Axon hatchback (UK) - a 2 seater hatchback, carbon fiber chassis,
>> gasoline engine, claimed 100 mpg
>> ( btw this vehicle is an entry into the Automotive X-Prize Contest
>> for best most practical commuter car)
>> see http://www.axonautomotive.com/cars.html
>>
>>
>> Jeromy Clarkson of BBC's Top Gear ( a UK auto review TV show)
>> criticizes
>> electric vehicles, HeVs, and PHEV and because of the high cost and
>> low energy density of batteries ( which means extra weight and lower
>> range)
>> He prefers using either a conventional diesel or gasoline engine to
>> power a
>> vehicle.
>>
>> ----------
>>
>> This comes as a bit of surprise. I would think the limited range of EV's
>> would not be much of a problem in the UK. How often do Britains drive
>> more than a hundred km or so? Or is the price of electric versus high
>> mpg just too much.
> I think Clarkson's argument was that hauling around all that extra weight
> in the end burns up more energy than running a straight gas/diesel engine.
> Motors have a different torque curve than engines so it's not that cut and
> dry, but still something to ponder.
>> One of the EV's shortcomings in the US market is the longer distances
>> that Americans want in their vehicles.
> Not to mention the fact that half of us drive around in snow for half the
> year.
> A local talk show host, who drives a Hummer H2, cracked after the first
> serious snowfall the one year "Hey, all you hybrid drivers... how's that
> working out for you? Getting thru the snow okay with ALL THAT POWER?".
> On a more serious note, a local car Q&A guy told of driving an electric
> car to a nearby town (about 30 miles, fairly hilly). The trip there was
> nice, sunny weather, car zipped right along. Then they headed back. It
> started raining, wipers on. It got cold, heater on. It got dark,
> headlights on. Batteries drained, car slowed, and they barely made it
> back.
> Hybrid or even electric works fine in Cali or Florida. WNYers need petro
> engines, and often four wheel drive.
> LG
> --
Isn't the problem with both electric and hybrid vehicles is battery
disposal? Which no one is yet talking about?
I like the idea of compressed air, but heat and wipers are necessary here in
the northwest as well as a lot of other parts of the country. How would you
get heat out of something that gets colder when you use it? If you have ever
used and air tool constantly and looked down and seen frost forming on the
tool in 80 degree weather. Wouldn't these temperature changes be internally
in air engines and lead to component failure?
Richard W.
Posted by vaughn on June 6, 2009, 5:13 pm
> Isn't the problem with both electric and hybrid vehicles is battery
> disposal? Which no one is yet talking about?
No. There is no problem with battery disposal. Dead lead acid batteries
have long actually been worth money for their metal salvage value. This is
why most battery stores charge you a "core charge" if you do not turn in an
old battery when you buy a new one.
There is at least one organization out there that will happily pay the
shipping and supply the special boxes to receive NICAD, NIMH, & Lithium
rechargable batteries for recycling. The metals and chemicals are not only
recyclable, but worth money!
> I like the idea of compressed air, but heat and wipers are necessary here
> in the northwest as well as a lot of other parts of the country. How would
> you get heat out of something that gets colder when you use it? If you
> have ever used and air tool constantly and looked down and seen frost
> forming on the tool in 80 degree weather. Wouldn't these temperature
> changes be internally in air engines and lead to component failure?
That cooling as the air expands is part of the problem with air energy
storage. The cooling limits the expansion of the air, so you get less
energy from it. There are ways to design an air engine to minimize the
effect, but they add cost, weight, size, and moving parts. Another big part
of the problem is that there is a corresponding HEATING of the air as it is
compressed. You pay for that heat in extra energy that you must add to turn
the compressor, but that extra energy is almost always wasted in the form of
heat. That is why you see lots of cooling fins on a compressor.
Vaughn
Posted by robert bowman on June 6, 2009, 6:56 pm
Richard W. wrote:
> I like the idea of compressed air, but heat and wipers are necessary here
> in the northwest as well as a lot of other parts of the country. How would
> you get heat out of something that gets colder when you use it?
That question was addressed years ago with reference to the early
Volkswagens. Build a fire in the passenger compartment.
Posted by News on June 20, 2009, 12:32 pm
> I think Clarkson's argument was that hauling around all that extra weight
> in the end burns up more energy than running a straight gas/diesel engine.
> Motors have a different torque curve than engines so it's not that cut and
> dry, but still something to ponder.
Clarkson is an idiot. The extra weight is not so much of a problem when
moving, like pulling boat along. Much energy is used to get the vehicle from
rest. Using brake regen using supercapacitors the kinetic energy used is
clawed back so roughly equals out.
> Hybrid or even electric works fine in Cali or Florida. WNYers need petro
> engines, and often four wheel drive.
No you need a small efficient auxiliary unit to drive the ancillaries. A
continuous burn warm air heater can be 85-90% efficient us using fuel, while
an IC engine is only 20-25% efficient.
The technology for the electric car is here. The UK government recently
announced plans to promote EV's.
A car is made of rather cheap poor heavy materials. Pressed steel is the
body. There is more pressure on cost, than weight with a substantial part
of the cars weight made up of the heavy body. In carbon F1 cars the
bodyshell weights almost nothing by comparison to its powertrain in
percentage weight of the total vehicle.
Lighten a car body and add lithium batteries, regen braking and motor in
wheel hubs, and you get to around 150-200 miles range. And that is ignoring
advances in supercapacitors.
Initially electric car usage will be more urban/commuting than fast highway
cruising, as that is the vast percentage of driving, but every little helps
and towns and cities will be cleaned up promoting better public health and
far less noise pollution. Better aerodynamics can improve high speed
economy, as can trading cornering performance by eliminating fat soft tyres,
giving lower rolling resistance on taller wheels and harder tyres.
It is feasible to produce an electric car that is suitable for a second car
at least right now. One that does the school run and takes you to work and
the shops. It will not do a 400 mile trip too well unless a 45 minute break
and clipped into a charger. On-board fossil fuel chargers may be useful for
"long range" vehicles.
With what we currently know, the single most important step is going from
lead or nickel batteries at around 30-50 mile ranges, to lithium that will
give 150 mile ranges or more.
Lithium batteries are at around the 700 MJ/ton mark now. The very best
nickel metal hydride are less than half that. A small car needs around a 50
Kwh, 180 MJ, energy in the "tank". In NiMh that's 3/4 ton, with Li-Ion it
is more like a 1/4 ton.
A litre of diesel is about 10 Kwh, burned at around 20% efficiency. 50
litres of diesel is equivalent to 100 KWh of battery. So the equivalent of
25 litres of diesel in an electric power train at around the 400 kg mark is
possible with Li-Ion batteries.
50 litres of diesel equivalent takes us up to equivalent of half a ton of
battery. That is very comparable with the weight of a normal internal
combustion engined powertrain. Electric cars require very little else
besides the batteries, just small motors. No radiators, massive heavy,
complex transmissions, exhaust systems, anti-vibration mounts and the miles
of pipes and ducts that surround a current IC auto setup. An electric car
gives superior packaging of the batteries and mechanicals than the current
IC cars and can give superior handling, and safety, in a lower centre of
gravity.
..and I haven't mentioned supercapacitors either. These can more than make
the electric car feasible: in the short and long term.
Then there is the spin offs to home and off-the-grid uses. The drive for
electric autos, that is where the focus is, will cascade into homes.
>>
>>>
>>>> What would supply the energy to compress the air and why would we not
>>>> just
>>>> run that energy source a directlly as possible to avoid more energy
>>>> losses
>>>> in an inefficient storage system?
>>>
>>> The goal/advantage would be to pressurize the air so
>>> the its energy density would be greater than the
>>> fuel source that it replace. When this is accomplished
>>> one can achieve the ultimate reward - a high density
>>> energy source coupled with an extremely efficient,
>>> simple and reliable engine/motor . One of the barriers to
>>> making a EV - is that while electric motors are simplier
>>> and more efficient than than gasoline/diesel engines
>>> - the energy density of the best EV fuel cells are about
>>> 1/3 to that of a petrol based one. So any efficiency
>>> gained from having a lighter more efficient engine/motor
>>> is lost because the increase weight of the energy source.
>>> By changing engine performance and lowering the
>>> overall vehicle mass a conventional diesel/gas cars to
>>> get between 60 to 100 mpg - yes - they go a bit slower
>>> ( 0-60 mph in 15 seconds) they can not go as
>>> fast maybe ( top out at 85 mph ) - but they get
>>> 60 to 100 mpg. So where do they exist? Well
>>> you have to go to the Europe or Japan....
>>>
>>> here are two examples that I know of.
>>>
>>> 2005-2009 Toyota Aygo (Japan/UK/Europe) - a conventional 4 door sedan
>>> using a 3 cylinder diesel, about 65 mpg
>>> ( sister cars = Peugeot 107 and Citroën C1 )
>>> see http://en.wikipedia.org/wiki/Toyota_Aygo
>>>
>>> 2010 Axon hatchback (UK) - a 2 seater hatchback, carbon fiber chassis,
>>> gasoline engine, claimed 100 mpg
>>> ( btw this vehicle is an entry into the Automotive X-Prize Contest
>>> for best most practical commuter car)
>>> see http://www.axonautomotive.com/cars.html
>>>
>>>
>>> Jeromy Clarkson of BBC's Top Gear ( a UK auto review TV show)
>>> criticizes
>>> electric vehicles, HeVs, and PHEV and because of the high cost and
>>> low energy density of batteries ( which means extra weight and lower
>>> range)
>>> He prefers using either a conventional diesel or gasoline engine to
>>> power a
>>> vehicle.
>>>
>>> ----------
>>>
>>> This comes as a bit of surprise. I would think the limited range of
>>> EV's would not be much of a problem in the UK. How often do Britains
>>> drive more than a hundred km or so? Or is the price of electric versus
>>> high mpg just too much.
>>
>> I think Clarkson's argument was that hauling around all that extra weight
>> in the end burns up more energy than running a straight gas/diesel
>> engine. Motors have a different torque curve than engines so it's not
>> that cut and dry, but still something to ponder.
>>
>>> One of the EV's shortcomings in the US market is the longer distances
>>> that Americans want in their vehicles.
>>
>> Not to mention the fact that half of us drive around in snow for half the
>> year.
>>
>> A local talk show host, who drives a Hummer H2, cracked after the first
>> serious snowfall the one year "Hey, all you hybrid drivers... how's that
>> working out for you? Getting thru the snow okay with ALL THAT POWER?".
>>
>> On a more serious note, a local car Q&A guy told of driving an electric
>> car to a nearby town (about 30 miles, fairly hilly). The trip there was
>> nice, sunny weather, car zipped right along. Then they headed back. It
>> started raining, wipers on. It got cold, heater on. It got dark,
>> headlights on. Batteries drained, car slowed, and they barely made it
>> back.
>>
>> Hybrid or even electric works fine in Cali or Florida. WNYers need petro
>> engines, and often four wheel drive.
>>
>> LG
> Oh bullshit, any front wheel drive will take you just about anywhere all
> winter.