Tesla - And whats it really like owning an EV?

Tesla - And whats it really like owning an EV?

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Scuffers

20,887 posts

274 months

Monday 9th March 2015
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Vanin said:
The easily interchangeable batteries would make more sense with photovoltaic as you could leave a spare battery at home on charge all day
Ideally, yes, the only issues are:

1) cost - the second battery would be some £10k+
2) weight, ie more than half a tonne...

EddieSteadyGo

11,865 posts

203 months

Monday 9th March 2015
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Scuffers said:
I have to say, Elon Musk is an impressive guy. He comes at things head on and find solutions.

The fact that he can design and put on sale a car like the P85d, which is so far ahead in performance terms of the offerings from the premium car manufacturers, is very impressive indeed.

It makes me want a Tesla smile

Scuffers

20,887 posts

274 months

Monday 9th March 2015
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You think tesla is impressive, remember, he also owns and started up space x.


Vanin

1,010 posts

166 months

Tuesday 10th March 2015
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Scuffers said:
You think tesla is impressive, remember, he also owns and started up space x.
What is your opinion of Toyota's fuel cell approach?

Scuffers

20,887 posts

274 months

Tuesday 10th March 2015
quotequote all
Vanin said:
What is your opinion of Toyota's fuel cell approach?
I simply don't get it.

nothing against fuel cells per say, the issue is where do you get the hydrogen from?

Currently, the industrial way is steam reforming from guess what? yes, oil and gas!

(Currently, the majority of hydrogen (~95%) is produced from fossil fuels by steam reforming or partial oxidation of methane and coal gasification with only a small quantity by other routes such as biomass gasification or electrolysis of water.)

so what exactly have you achieved in making hydrogen from oil?

if you argue to use electrolysis, where does the electricity come from? then factor in that at best, fuel cells are only 40-60% efficient, that makes them less efficient (as an electrical storage system) than the current Li batteries.

the next problem is that to equivalence the energy content of 60l of petrol (~550Kwh), you need some ~16Kg's of hydrogen.

now that does not sound like a lot, BUT to store that mass of hydrogen means doing so as a liquid, and that's getting somewhat interesting in terms of the 'tank'.

some good info in this: http://www.electrochem.org/dl/Interface/fal/fal04/...

so, most cars are using compressed hydrogen, at up to 700Bar, but even at those pressures, you don't get much mass of hydrogen is a pretty big tank, at which point I should mention that you are driving around with a pretty effective hydrogen bomb in the car.

now, yes you can made safe tanks, the problem is they are heavy, and what happens in an accident? unlike petrol that may split the tank and leak out, or even catch fire (but in reality that almost never happens outside of hollywood), with hydrogen at 700Bar it's not going to be so passive.

if we much go fuelcell, the I think methanol fuel cell is a much better way forward, methanol is relatively safe to transport and store (much like petrol) and has very good energy density.

they are already a consumer product for the leisure industry (boats/RV's/etc), and methanol can be produced using all kinds of processes that don't involve oil or the like.









Super Slo Mo

5,368 posts

198 months

Tuesday 10th March 2015
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I like the sound of methanol, but isn't it simpler to just burn it in a conventional IC engine? Or is the fuel cell version more efficient?

Scuffers

20,887 posts

274 months

Tuesday 10th March 2015
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Super Slo Mo said:
I like the sound of methanol, but isn't it simpler to just burn it in a conventional IC engine? Or is the fuel cell version more efficient?
basically, yes it's more efficient, the issues have been over scale and blocking of the catalyst by CO, but looks like that's been solved...

http://www.theengineer.co.uk/automotive/news/new-d...


Vanin

1,010 posts

166 months

Wednesday 11th March 2015
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Are they not doing well on Orkney and other places in Scotland without using fossil fuels?

http://scitechnews.co.uk/ev-hybrid/orkney-embrace-...


Scuffers

20,887 posts

274 months

Wednesday 11th March 2015
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Vanin said:
Are they not doing well on Orkney and other places in Scotland without using fossil fuels?

http://scitechnews.co.uk/ev-hybrid/orkney-embrace-...
lol!

and just who do you think is subsidising all this green-ness? (and by how much?)