piclist 2007\03\20\083803a >
Thread: : [TECHO] The Air Car - zero pollution and very low running costs- gizmag Article
www.piclist.com/techref/index.htm?key=air+car+zero+pollution
BY : Russell McMahon email (remove spam text)

Matthew McMahon says -

Subject: The Air Car - zero pollution and very low running costs -
gizmag Article

> http://gizmag.com/go/7000/

French designed. Indian made.
300 km range claimed.
Approx 10% of petrol running costs claimed.
E1.5 per 300 km fill.
68 mph toppppp speed.
Lessee.
E1.5 ~~= \$US2? ~= \$NZ3.
Approx 2 litres petrol at NZ prices.
So 150 km/litre or about 375 mpg-US or 425 mpg imperial.

No mention of pressure used.
90 m^3 of gas said to be stored.
You'd be (very) lucky to get 1 m^3 of storage in a small car so that's
90+ atmosphere =~~ 1500 psi or 9 MPa.
Probably double that.
Would need a very many stage expansion motor to handle that
efficiently.

Very very (very ...) roughly using expanded energy equivalent, 90 m^3
at 1 atmosphere = 90 m^3 x 100 kPa  = 9 MPa energy.
9 E6  /1000 kW/W  /3600 hr/sec = 2.5 kWH = about 10% of what I
calculate the cost would buy in energy equivalent electricity. And 2.5
kWh is utterly insufficient for the task as 20 kWH (see below) is
rather skimpy. Possibly a missed decimal somewhere in my figures but
... .

>From an electricity point of view. \$NZ3 buys about 20 kWH of
electricity or the same energy content as 2 litre of petrol.
150 km on a litre of petrol given equivalent energy content is "rather
good".

I very strongly suspect that their energy costing claims are
fallacious.
I'd be happy to be proven wrong.

E&OE as always

Russell

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