I belive that in New Zealand compressed natural gas has been used for years to fuel cars.
How big are the Tanks?
How does it compare to LPG?
Who makes mixers/comverters?
Where can I buy a natural gas compressor, for home and how much?
How much does it cost to convert a car?
If we have an abundance of natural gas and it is cleaner then petrol or LPG, as I have been lead to belive, then why is the government not promoting the development?
Any one using or developing CNG in Australia?
Any thoughts!

Your right, its very cheap to run, although the setup costs are huge im told.

I couldnt find any pricing info anywhere :S

Let us know if you do

Ford actually put a CNG Falcon on the road for testing in the mid 1990s, I think about 20 of them(where are they now?) Honda had a CNG powered civic,Japan, and USA market (google)
Compressions of 12/1, 14/1 are needed to make them go well, Dual fuel out.
Advantages, don't need petrol companies, If you have the gas on at home,a small dedicated CNG compressor can fill overnight, a reasonable size tank will get a 300-400K range.
Disadvantages, really for local use, no refill facilities once you hit the highway- Petrol companies have got you again!- they are not interested.
This is a much better alternative power than having F*cktards like captain Kev giving a fortune to Toyota to manufacture Camry's with near dead technology prius systems. The prius(AKA pious- check out,and listen to the f*cktards that drive them) was only put on the road to satisfy California regulations, the Yanks have gone straight electric, and will have a Chev on the market within 3 years.
The CNG technology is up and running, and Oz has unlimited CNG. Pity we are stuck with a PM that is only interested in cruising the world looking for photo opportunities.

Kiwis once had the biggest CNG car numbers on the road world wide, from people I have talked to about it, majority were dual fuel conversions , would have not been that responsive on CNG due to low compressions,Laterly, they seem to have abandoned ship on CNG, not that many on the road over there now.

this information lifted from a US site

LPG = 2500 btu's per cubic foot
CNG = 1000 btu's per cubic foot
LPG stored at approx 125-175 psig, depending temperatures, could be much lower or much higher but almost never over 250 psig;
CNG stored at pressures to 3600 psig.
LPG is a pressurized liquefied gas
CNG is a pressurized vapor
LPG tanks are relatively inexpensive, about $400 USD for a 40-gallon tank.
CNG tanks are VERY expensive, about $1000 for an 8-gallon equiv tank.
LPG driving range is about 4 to 5 times as far as the same storage space CNG.
LPG is almost always 80% that of gasoline, sometimes better.
CNG is almost always 60 to 70% that of gasoline.

Be VERY careful of marketing hype claiming GGE. All that does is to change the rating of the fuel into gasoline gallons equivalent. In that respect, CNG would equal that of gasoline.

If you have an old home pump for CNG, they had to be reclocked at the factory every 2000 operational hours, changed to either 3,000 or 4,000 hours, roughly once every 1 to 2 years, depending on usage. These units would fill at the rate of about 115 cubic feet per hour, or about 8 hours for the equivalent of 8 gallons.

According to Chris Riley (car guide Frankston/Hastings Leader) July14 2008, Most taxis in Germany run on cn-gas. The b-class benz's being the wepon of chose. They get about 300km out of tank.
Does beg the question, why our Kev gives toyota big dollars to develop camry hybrids. When the people who are hurtiing the most by fuel prises, are the commuters from outer suburbs who can't afford new cars, let alone hybrids. Unless our Kev wants to turn the outer suburbs into slums, I sugest he spends our dollars on subsidising developing of after market cn-gas systems and infrastucture and not camry's! Or Would the big oil company's not approve? Sure it would not take them long to screw up the prise like with lp-gas, but maybe not so easy to.

Petrol companies will never go along with a fuel that they do not have exclusive control over, By installing a home compressor/filler the price you pay is the same as what you pay to boil a jug or heat your house,I saw somewhere recently that a CNG car home fueled cost about $5 per 100Ks to run, my EF 6 cylinder costs $10 per 100 at 67C litre lpg
This changes every day depending on what the petrol companies think they can get away with, I don't think any government would go along with daily price changes in home supplies of CNG
I recently asked the ACCC about LPG pricing, there reply said the price was deregulated in 1991,(WHY???????) the petrol companies can charge what they like. And as LPG is a waste product from petrol refining, 100% produced in Australia, Zero exported, and is in no way controled by overseas pricing of petrol It is insane that the federal government has not made any effort to regulate the price. This is a fuel they CAN do something about the price.
WHY DON'T THEY?????
Start with LPG, then CNG,can't see why the can't- there are votes in it, and that is what the games are all about.

I have seen a guy in SA uses CNG

CNG is stored at a pressure of around 20,000 kPa. It takes up a lot more room than LPG and therefore cylinders are both stronger (heavier) and larger. CNG is more knock resistant than LPG and therefore operation with higher compression ratios or with higher boost pressure is possible. Companies such as IMPCO and OMVL make mixers for CNG (similar to the mixers they supply for LPG) but gas injection systems (like the system found on the Honda Civic GX) are much more reliable and produce better power and economy.

All buses in Australia that are baged as "Gas-powered" run on compressed natural gas and not LPG. The fuel is stored either under the floor of the vehicle or on the roof (the latter requires the cylinders to be shielded by a fibreglass cover).

Regards,
Dave

So in short.. CNG requires almost all your boot to give you the same travel as a normal tank of LPG?

And it requires more mods to get the same power.. ie head shave etc

And I'm not sure of the price differences either..
What I'd like to see, to put the prices into perspective.. is cost per 500km for petrol, LPG and CNG.... has anyone ever done it?

A diesel motor would be an Ideal CNG conversion as it's already higher compression and generally stronger. As 90% of peoples trips in Oz are less than 100klm a normal sized tank would be fine if you fill up each night at home.
Commercial systems are available for forklifts and such.

Could a CNG car that hadn't had it's compression increased too far run LPG as well?

No. LPG requires a different cylinder, different regulator, and different tune compared to CNG.

Regards,
Dave

LPG is exported to China for some ridiculously low price

LNG!

Regards,
Dave

Hey mate do you know what the cost of a CNG setup is?