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A Practible Electric Car?

A Practible Electric Car?

RE: A Practible Electric Car?

(OP)
It shifts the pollution to the generation of the electricity (which can be clean or dirty) rather than directly burning the hydrocarbons.

RE: A Practible Electric Car?

No, you must be wrong, ewh, they say:

Quote:

Zero Emissions Equals Zero Guilt

Lots of cars claim to be planet-friendly. At Tesla, we set out to build a “zero emissions” vehicle that can‘t be accused of being just an “emissions elsewhere” vehicle. Our lithium-ion battery pack delivers unprecedented energy density in a smaller footprint. So you can actually enjoy greater performance behind the wheel without an ounce of guilt. "
This is a page which shows not a single wind turbine, not a wind farm and not a power station, just scenery.

So, ewh, they say this isn't an "emissions elsewhere" vehicle. Of course, they don't justify that claim and they ignore exactly the points made in the SUV thread.

One item of information lacking was the typical battery life... if it is like my laptop, mobile phone, etc etc  there'll come the day when I run out of charge miles from anywhere... what's the equivalent of a spare gas can?

I would guess Ted Danson and the green Hollywood Elite bought all the first 100 cars (http://www.nndb.com/people/690/000022624/ ... )

Next thing you know these guys will be pointing the finger at the Prius owners and accusing them of being polluters!

(Why did Michael Chriton's "State of Fear" have such a poor image of Hollywood Stars turned environmentalists? is that modelled on any one?)

JMW
www.ViscoAnalyser.com

RE: A Practible Electric Car?

Just an addendum, I visited the site http://oceana.org/ and it appears pretty good so it must not have been Ted Danson....

JMW
www.ViscoAnalyser.com

RE: A Practible Electric Car?

(OP)
Ah, but they state that "we set out to build...", not that they achieved this.  You are right that unless they only recharge with electricity which was cleanly generated, they are only moving the pollution.
I don't think it can be considered a replacement for all cars in all situations, just that seems to be much better situated for current urban driving than a hydrogen vehicle would be, for example.

RE: A Practible Electric Car?

I found the site fasinating enough to read the FAQ's.  They say that the battery life is 500 recharges.  At 250 miles/recharge they're claiming 125,000 miles on a set of batteries.

Their "zero emissions" is just nonsense.  They don't even account for the emisssions from fabrication of the steel/plastic/carbon fibers used in construction, or the emissions from the coal-fired power plants that provide electricity.  It takes a well-defined number of ergs of energy to move a known mass from one point to another--you just can't fool Mother Nature.  Those ergs come from somewhere and it is really disingenous to claim that they don't.  It could be that the whole process is a point or two more effecient than a Prius, but I would be suprized if it were more than that.

David

RE: A Practible Electric Car?

Their caveat is the it's zero emissions from oil usage, since US electrical production uses coal, wind, hydro, etc., but not oil.

TTFN



RE: A Practible Electric Car?

I think there is still about 5% of the power generation capacity in the U.S. that is fuel-switchable between natural gas and #2 resid (oil).  

Wasn't some gas/diesel used in the transportation of parts to the fabriction plant or ore to the foundry?  The zero oil contention is just marketing puffery.  

It still looks like a pretty cool vehicle.

David

RE: A Practible Electric Car?

And, it's almost as peppy as a Turbo911 with the whizbang transmission.

http://www.eurotuned.com/0-60.htm would put in the fastest 3% of the cars listed there.

TTFN



RE: A Practible Electric Car?

It takes a well-defined number of ergs of energy to move a known mass from one point to another--you just can't fool Mother Nature.

Huh?  Not that it's relevant to the thread, but how many ergs does it take to move 100lbm 10 feet horizontally?

RE: A Practible Electric Car?

For a regular car that gets 20 mpg, it takes 1.1742E+11 ergs;  your mileage may vary winky smile

TTFN



RE: A Practible Electric Car?

Ergs???

Watts! Joules! Kilograms! Metres!

Mother Nature measures in S.I. these days. wink

----------------------------------
  Sometimes I only open my mouth to swap feet...

RE: A Practible Electric Car?

The units weren't related to the answer I was after - use whatever units you like, and tell me how much energy is required to move a known amount of mass by a (horizontal) distance.
 

RE: A Practible Electric Car?

Let's start simply be temporarily ignoring rolling friction, sliding friction and media (wind, water, other media) resistance.

The first component of energy use will be acceleration.
Variable.
Now, in a propeller driven, frictionless, vehicle such as a boat or a hover craft the energy to decelerate will equal the energy to accelerate.
In a vehicle with heat disipation braking, the energy will be one half of the energy used by our propellor driven vehicle.
That is only the energy used for acceleration.
In a vehicle that uses an efficient regeneration system of braking, almost all of the acceleration energy may be returned to the source. Think efficient, battery powered, electric vehicle.
Now we can consider the variables of friction losses of several types.
Would these ergs be the type described in?:
http://www.pbs.org/wnet/africa/explore/sahara/sahara_topography_lo.html

respectfully

RE: A Practible Electric Car?

Quite a performance difference and a quanit "retro" look web site....

I notice it has "climate control" (no pun intended, we hope).

By the way, in the UK, milk has been delivered by electric "milk floats" for ever since I can remember. Top speed around 10-11 mph, I think.

JMW
www.ViscoAnalyser.com

RE: A Practible Electric Car?

Then there is the General Motor EV1, no longer in the market:

"The EV1 was the first production quality battery electric vehicle produced by General Motors in the United States and, at the time, was the only electric vehicle in the history of the company to bear the "General Motors" badge."

http://en.wikipedia.org/wiki/General_Motors_EV1

cheers,

Joseph

RE: A Practible Electric Car?

Ah.

The British Milkfloat.

Built out of girders with a tonne of Nickel Iron batteries... (they used to be NiFe, but who knows these days...)

Do try not to hit one coz you'll come off worse...

RE: A Practible Electric Car?

The older milk floats had 5/8" teak comb jointed battery boxes, if not teak then some pretty durable timber that has to withstand battery acid leaks and the weather.... I have about a dozen of these in assorted sizes which pretty up very well indeed... they cost me nothing since I got them from a company that was scrapping the vehicles and salvaging the betteries but dumping the boxes.
Latter floats have fibreglass battery boxes.
I hate to see wood go to waste...

One school mum decided to have one coverted for the school run but alas, she mistook the difference between average traffic speed and milk float top speed. These may match for a milk float but it meant she was an even worse obstruction on the school run than most other mums.... where the trafffic could normally top out at 30-40mph, they were now stuck behind here at an 11mph max.

JMW
www.ViscoAnalyser.com

RE: A Practible Electric Car?

The kinetic energy of a 60 mph, 3500 lb car is about 570 kJ.  That's the energy stored in 0.45% of a gallon of gas.  Unless all you're doing is starting and stopping, the regenerative braking retrieves very little of the energy consumed on a trip.

TTFN



RE: A Practible Electric Car?



MIT, Prof. Mitchell from GM and Frank O. Gehry are developing a city concept car. The city car will have high tech wheels with embedded electric motor and suspension.



For more information go to

http://www.archinode.com/mitcar1.html


atom

RE: A Practible Electric Car?

60 mpg? what is green about that? A 4 seater that gets 30 mpg is as efficient, safer, weatherproof, and has a top speed of 90 mph or more.

Ridiculous.

The MIT car is even worse.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: A Practible Electric Car?

Well said Greg.  I wasn't impressed by the figure either, I believe certain european or Japenese sub compacts may be at a similar value with 4 seats.

Of course in most cars all 4 seats aren't used so saying a 4 seater that gets 30mpg is as efficient as a 2 seater 30mpg is a simplification.

RE: A Practible Electric Car?

I guess it depends what you mean by efficient.  By that logic an 8 passenger SUV at 15 mpg is equally as efficient as the Go Car.  Of course there's usually just one or two passengers, and the mileage doesn't go up to 60 mpg with just two passengers.  (Never saw cars rated in person miles per gallon before.)

I wasn't trying to say the thing is the "wave of the future" or phenominally amazing, just pointing out a (relatively) efficient  vehicle that's on the road.  I was also wondering how that was street legal, considering the DOT wouldn't certify the Smart Car due to safety concerns, but thats another thread.  

As for the OP, the car looks great.  Don't see how it overcomes the established problems with electric cars, though (range and battery reliability/volatility).  My thought on the shifting of emissions issue: isn't it true that point source energy production is preferable because of higher efficiency and use of heavy equipment like scrubbers and the like to reduce emissions?  (OK, the nasty stuff is still there, but its not air emissions at that point)

Also, I don't see the modern world getting away from providing electricity to homes -ever-, so isn't it logical to assume that the electrical generation technology will continue to improve and evolve?  And if so, doesn't it make sense to develope electric cars to anticipate that eventuality?

RE: A Practible Electric Car?

Yes, the emissions are concentrated, but the companies are fighting the scrubbing tooth and nail.  And the sources are converting to coal and water.  While coal is relatively plentiful in the US, it's not a particularly clean burning fuel.

TTFN



RE: A Practible Electric Car?

Oz has 200 years of coal. The recent paper on it suggests that nuclear is more expensive than current coal power, but cheaper than clean coal, with CO2 sequestration.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: A Practible Electric Car?

The caveat is that most coal reserves are calculated on the CURRENT consumption, which in the US, is almost entirely used for electricuty.  A drastic shift to electric cars would crank up the consumption of coal considerably, since hydro is pretty much maxed out already.  This would have to be coupled with a drastic increase in the number of coal-fired generator plants, which will substantially add to the ecological cost of converting to electric cars.

TTFN



RE: A Practible Electric Car?

It's OK, the UK has plenty of coal left after the government pretty much shut down the coal mining industry in the 80's/early 90's.

Wouldn't be so easy to restart production etc but there you go.

Plus there are numerous other ways to produce electricity, some need further development others just have large up front costs with the current technology.

That said in the medium term I think a plug in (possibly series) hybrid would have been a better idea, though ewh it does look pretty cool.

RE: A Practible Electric Car?

So the coal is there for the foreseeable future, agreed.  Andybody have any comments on how much more efficiency we can squeeze out of the plants and/or how much we can or will clean the emissions from these point sources?

As for CO2, I've got a plan.  Its very complicated.  It involves an extremely complex carbon sequestration device.  

It's called a tree.  Plant many.  Cut them down after about 20 years and plant some more.  Repeat.  Use them to make things out of *wood*.  The engineering historians may be able to shed some light on how that was once done.

RE: A Practible Electric Car?

How long does a structure last, typically? 30 years? 100 years? What happens to the wood in that structure then? Unless you can recycle it into something permanent then all you've done is taken it out of the carbon cycle for an additional 30-100 years. Not enough to make a difference IMO.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: A Practible Electric Car?

You bury it in an old coal mine of coursesmile

More energy efficient might be to use it for fuel but then as you say, you're returning most of the CO2 to atmosphere.

RE: A Practible Electric Car?

Well short of Kenat's idea (which actually could work), think of it this way: by increasing the amount of products made of wood you've created a carbon "warehouse".  Carbon flows into the warehouse, and eventually out of the warehouse.  Once you reach steady state (full warehouse) flow in equals flow out.  This might seem like you've gained nothing.  However, for every pound (or kilo, whatever you crazy foreigners use) of carbon in the warehouse there is one less pound of carbon in the atmosphere.  This can't solve the problem if we keep dumping carbon into the atmosphere, of course.  But given a big enough warehouse (lots and lots of wood products), it could definitely buy us time, and maybe a quite a bit of it.  

A properly maintained wooden structure can last 100 years, easily; maybe more with modern moisture control techniques.  Other, more disposable products may have a life span of a few months to a few years.  But each item increases the inventory of the "warehouse".

Have I fallen prey to some logical fallacy here?  Feel free to poke holes in the argument.

RE: A Practible Electric Car?

The fallacy is that there are already carbon warehouses, e.g., the fossil fuel deposits.  The problem is not that we don't have a carbon warehouse, it's that we're releasing ever increasing amounts of carbon from those warehouses.

The CO2 in the atmosphere cannot be readily re-warehoused, not without burning a whole bunch of energy to get there.  How are you going to get the atmospheric carbon into wood without cracking the CO2, which requires at least as much energy as was released when the carbon was originally combusted?

TTFN



RE: A Practible Electric Car?

What is photosynthesis, Alex? ;)

RE: A Practible Electric Car?

Your logic seems to work YoungTurk.

Lets build lots of HMS Victory's.  Must be one of the oldest wooden structures around still in fairly good repair (yes I know a lot of her has actually been replaced over time).

Of course we still might be better burning most of that wood/vegetation in place of digging up new fossil fuels.  Now if we can get the wood or other vegetable matter to grow faster than we can combust or otherwise turn it into useful energy we can start building victory's or burying it.

I propose a new unit.  The Victory.  An amount of sequestered carbon equivalent to that in the HMS Victory.winky smile

RE: A Practible Electric Car?

Even if carbon neutral, the Plank Institute discovered that plants also produce methane. Not much, but some and hence we would appear to realise a net gain in atmospheric methane.

JMW
www.ViscoAnalyser.com

RE: A Practible Electric Car?

But if we eat cows and other herbivores faster and kill the pesky termites (hence helping preserve the 'victories') this would probably adequately compensate.

RE: A Practible Electric Car?

Photosynthesis, sure, but how much energy are you going to burn to plant and maintain the 10 billion trees needed to warehouse the carbon?  Don't forget fighting the forest fires and the pests, and relocating the people that havwe already encroached into the areas that would be reforested.

TTFN



RE: A Practible Electric Car?

I agree wholeheartedly regarding releasing carbon from the existing warehouses, those being primarily coal and oil deposits.  But we can't refill those warehouses with any current technology.  

We can build a bunch of USS Constitutions, though! (Hey, she's still afloat, which totally one-ups the HMS Victory).

As far as planting, there are very efficient ways to accomplish that.  Which you choose depends on your purpose.  I recently saw a technology which dropped seedling from an aircraft at relatively low altitude.  Or you just use old farming technology.  If you're planting seedlings, the energy cost is pretty low per tree.  Even lower if you use seeds.

I've not heard the methane isssue before.  I'll read up on it.

RE: A Practible Electric Car?

Victory is I believe older than the USS Constitution.

Trees probably aren't actually the best choice if you just want to trap a lot of CO2 and not necessarily build things from the resultant material.  There are I believe other types of vegetation which grow faster/absorb CO2 relatively faster.

Saw one scheme for essentially passing power plant exhause gases through water filled with algae.  Plan being the algae would use most of the CO2 and could then be turned into alchol.  Seems the biggest problem is getting light to the algae, it tends to stick to the sides of the container/light pipes etc blocking light.

RE: A Practible Electric Car?


GM plans to build a plug-in hybrid vehicle, here is the article.

http://transport.seekingalpha.com/article/21671

"... the Saturn plug-in hybrid will include lithium-ion batteries, two interior permanent magnet motors..."

RE: A Practible Electric Car?

I was off by a factor of 40.  The CO2 uptake was over 40 years, so to completely compensate for the annual CO2 release, you'd need 400 billion trees, just for the US alone.  Since the US consumes ~1/6 of the total world supply of energy, you'd need 2400 billion trees to stop the growth in CO2 in the atmosphere.

TTFN



RE: A Practible Electric Car?

Better get planting then.

RE: A Practible Electric Car?

IR, I'll take you at your word on the math.  At ~500 trees per acre (a health forest, give or take) and 640 acres per sq mile I figure 1.25 million square miles.  That about 1100 miles square.  Doable, but not necessarily practical.  A start, perhaps.

Volunteers for a "Johnny pineseeed"?  

Actually, I'm sure monocots (sp?) such as bamboo could do a better job of carbon sequestration than trees.  Would they be as useful afterwards, though?

KENAT: The HMS Victory is dry docked!  Whats the point of having a commisioned ship permanently in dry dock?  Crazy Brits!  Our Constitution, now theres and old boat that floats-  Here's to Old Ironsides! ;)

RE: A Practible Electric Car?

YoungTurk, I believe most of the UKs fleet is docked most of the time these days.  Is the Constitution still a commsisioned vessel?

RE: A Practible Electric Car?

Yes, the Constitution is still a commissioned vessel. She just we through an extensive overhaul several years ago to correct a problem with "hogging". After the yard work she made trip around Boston Harbor with a full Navy Crew.

RE: A Practible Electric Car?

^ Now thats pretty neat.  They'd have to jack up the range before I'd consider it practical, but still pretty neat.

There I was laughing at the Jaguar paint job, then I clicked over to the BBC story and saw one on the street.  Hilarious.

RE: A Practible Electric Car?

But the same question remains: what is the total carbon footprint? not just its fuel economy.

The problem caused by all the hype about the climate is that the wrong parameter is being measured and as a consequence these initiatives, unless they can project an even lower carbon footprint than conventional manufactured and powered vehicles as a consequence of a sufficiently sized market for these "green" vehicles, is that they can make the situation worse and not better.

JMW
www.ViscoAnalyser.com

RE: A Practible Electric Car?


Very good question jmw.

FYI..  I started thread730-172835 with links to a model known as GREET that evaluates the impact of plug-in EVs and other advanced technologies and fuels.

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