s13lover

Compresses Natural Gas.

For transit application, it’s the exact same thing used to heat homes. As of 1999, there were already 85,000 vehicles (mainly commercial and public transportation) on the road using CNG. These vehicles where supported by a network of 1,300 refueling stations across 46 states.

Why I like the stuff:

1. NO refining needed. Just pump the stuff out of the ground and straight into your car. Once the infrastructure is expanded, CNG would be so much cheaper than gas. Depending on the market, it has already seen times when it was cheaper than gas. I remember seeing a Ford video from 1995 that had a gas station with 87 octane at $.99 and CNG at $.69.
2. America has a huge supply of CNG. It is estimated that under PA, OH, and WVA that there is enough CNG to rival the oil under the Middle East (although those CNG reserves are spread out in many caverns).
3. CNG is much cleaner than gas. CNG has 1 carbon atom for every 4 hydrogen. Gas has 8 carbon for every 18 hydrogen. CNG also is always run at 17.2:1 regardless of the operating conditions, unlike gas which fluctuates and goes rich during warm up and full throttle.
4. Even with the 17.2:1 compared to the ideal 14.7:1 for gas, CNG get the same miles per "gallon" as gas.
5. The BTU's for CNG is slightly less than gas, but the octane is 130. This means that you can run much higher compress to make much more power.
6. CNG tanks are exponentially stronger than gas tanks. Can withstand a shot from a high caliber gun. However, the longest lasting of the tank types, composite wrapped, only last 15 years.
7. CNG is nontoxic and non-corrosive.
8. Reduced engine wear because of the fewer carbon atoms.
9. Possibility of being able to re-fuel at your house. Because the CNG is not refined in any way (sulfur added for smell) it is the same thing used to heat homes. Therefore, tap stations could be installed into your home heating lines to be used for refueling.

rx8wannahave

Great...now make it happen????

LOL

So what's holding it back?

Tamas

iTrader: (1)

It would be cool - and there are conversion kits available for piston engines. In many European countries, driving on CNG is quite common, and those cars can run on both CNG and gasoline, pretty much at the flick of a switch.
Never heard about a rotary engine running on CNG though - wonder if it was done already and how the Renesis could be converted. I suppose it shouldn't be too hard, seeing that they got the Renesis running on hydrogen.

vectorwolf

I wanna use CNG.

rx8wannahave

^Yeah...anything to get off the Middle East oil...

s13lover

We have a 5.0L Ford engine at my college that runs on both CNG and gas. A flick of the switch is all it takes to go from one to another. We also have a 5.7L Chevy from Japser that came already setup to run on CNG alone. Conversion kits run between $3500 to $6000. You can't really take advantage of the CNG's octane with those conversions though, because you have to keep the stock compression. But the timing gets changed when the CNG is in use to keep the power output similar (5% to 10% power loss).

globi

Why spend $5000 on a gasoline conversion kit. Why not spend $795 on a diesel conversion kit and run it on FREE waste vegetable oil? Note that vegetable oil has a much higher energy density than CNG as well.
http://www.greasecar.com/product_detail.cfm?prodID=17

Tamas

iTrader: (1)

That'd be great - if it was applicable to the rotary.
However I have never heard of a diesel rotary yet... was there one?

Have to admit though, running the Renesis with used veggie oil coming from McDonalds would be way cool

globi

Actually there have been diesel-rotaries:
http://www.der-wankelmotor.de/Motore...lls-royce.html

I was just giving a general answer to the 'CNG saving the world thing'.

Also, at least there are more diesel powered passenger cars than rotary powered passenger cars.
And in countries like France and Spain there are already more newly registered passenger cars with diesel than with gasoline engines.

Y&Y

Hey s13lover,

Well Honda already has something you've mentioned, its the civic gx. It uses the natural gas. And if you're in California, you can drive in the carpool lane without any passengers if you get the HOV sign and stick it in your window. You get 200mi per tank load. And it takes 12 hours to fully refill your tank. Ya thats the downside. The long refill sessions. But the good news is you can lease or buy a natural gas pump and have it installed in your garage. Well as long as you have a gas pipe that is. There are a some gas stations already providing natural gas.

So go ahead don't be shy and check it out. Here is the LINK

Tamas

iTrader: (1)

Heh, that's cool... that's essentially two engines in one it seems. The displacement of the second one is almost as big as our entire engine - 1.265 liter

therm8

I'm kind of partial to this, assuming it doesn't get debunked:

http://www.guardian.co.uk/science/st...627424,00.html

globi

Rolls Royce did this, because they didn't find another practical way to increase compression ratio on the rotary engine.

fray

iTrader: (1)

Y&Y not sure where you heard "12 hours to refill the tank".. I think that may be some misinformation...

One of my friends in the Bay Area has a CNG Honda Civic GX. When he goes to a fuel PGE CNG station, it takes about as long to fill up as it does at a gasoline station.

They make _HOME_ compressors so you can take NG, compress it and put it in the car. From what I have been told those can take a few hours to fill the tank simply because they have no reserve tank to put the already compressed fuel. (They compress as they fill.) Of course the advantage to this is.. drive home.. plug in the car to the compressor.. wake up in the morning drive to work. Repeat.. never to spend time again at a gas station filling up the car.

If someone made a CNG conversion for the RX-8, I'd definatly consider it. For local city driving it sure seems to be convienent!

Photic

Interesting. Might be BS, but the whole "Turns x on it's head" phrase is interesting.
If it can be proven, then great. Think of how many times standard beliefs have been turned on their head in the last 600 years. It's a little pompous for someone to make that statement without seeing it first hand, but it's not unreasonable for someone to be sceptical without seeing it.

Y&Y

I hope you're right...cuz I read that off the page where I got all the information from. There's no way I'll be at home for 12 hours straight......well actually if it was like saturday and I don't feel like getting......Anyhow 12 hours does seem a bit too unpractical.

Y&Y

Now that I'm thinking about it. This car(if there aren't too many problems, since the car just barely came out) can pretty much be a cheap and problem free. Since it uses natural gas, you don't have to

1. Have your injectors clean.
2. If oil is used. probably won't be done as much.
3. Fuel filter, who needs it, there won't be any large debris from clogging your injectors.
4. don't have to smog it ever....well maybe

The only real issue to check for from time to time would be leaks in the fuel tank, fuel line and engine. Hmmm I guess smokers won't be able to drive this car around. Well hypotheoritically, there would probably be less brush fires here in Southern California.

And hopefully, if there are going to be plenty of these civics on the road, it won't get riced out.

Japan8

A few articles to spark some more discussion...

Is CNG or LNG all that it cracked up to be?
http://www.rediff.com/money/2002/apr/25dalal.htm

A better cataylice converter?
http://www.hydrodrive.8k.com/ELECTRO...0CONVERTOR.htm

A study of the potential CNG market for consumers in California
http://www.its.ucdavis.edu/publicati...1/RR-01-12.pdf

International Association for Natual Gas Vehicles
http://www.ngvglobal.com/index.php

Fleet Rules Litigation
http://www.valleycleancities.org/Art...r06-10-04.html

GM "Prequel" instead of "Sequel"
http://www.evworld.com/view.cfm?sect...le&storyid=914

Hybrids and hydrogen
http://www.usatoday.com/money/autos/...uto-show_x.htm

s13lover

Y&Y -

The Civic is not the only CNG vehicle. Ford and especially Chevy make CNG and bi-fuel (use gas and CNG) vehicles.

The 12hr refueling is only for home compressors feeding off of your heating lines. I just filled a truck up yesterday with a private industrial compressor at my college. They aren't as fast as the ones that gas stations use, and it still only took 5 minutes on a 40 gallon equivalent tank.

As for the fuel injectors - if you run CNG only, the fuel injectors aren’t use. The CNG is premixed with the air before it enters the intake manifold.

Conversions are defiantly not worth it unless you’re running a fleet operation. But I think it is a great idea to by a CNG vehicle from the factory.

s13lover

On a side note, Honda was at my college today doing a presentation on alternate fuel vehicles. They brought along a CNG Civic and the FCX Hydrogen concept car. I got to drive the FCX and I must say, there's nothing like being behind the wheel of a $1.2 million car!