CNG v. LPG

[Houndoc]

E-85 is more PR then true improvement in many ways. The use of food crops for fuel has driven up world food prices (bad news for the poorest of the poor) and deforestation for farming has been happening in Brazil.

Cost is kept artificially high, not only because of farm subsidizes, but government restrictions/tarrifs on inported ethanol.

An alternate source of ethanol needs to be developed using non-food products. Research is being done on using prarie grasses, crop bi-products and even algae. Cool stuff, really.

 

[Greg]

my 2 cents. Savage Bros. have been working for a few years with cng in their heavy haul diesels . Some of the first #s they had were fantastic . They put the cng on a 425 cat. engine. Base horse power on diesel is 425 hp. With cng it went to over 2000. they were twisting off drive lines and breaking stuff every where . After some detuning, the last I heard, settled for around 750 hp with major engine life gains. Time between oil changes increased more than double . The biggest problem was teaching the drivers how to deal with the power increase and not tear up the equipment

I want to know more about this, I'm quite skeptical. You're saying a diesel that normally make 425 HP was making over 2000 HP? Burning CNG in diesel engines isn't anything new, but that's the first time I've heard a 4x power gain. Did they have to modify the motors? Are the engines still compression ignition? What about dealing with the reduced fuel (esp OTR Semis), due to it being compressed gas vs. liquid? You'd have to carry more CNG to get the same amount of mileage when it was running on diesel. I've very curious here.

 

[Broncoman]

I use to drive for a competing co . Their driver and I got to know each other and he would tell me what was going on. I havent seen him for a few years so I don't know any thing new or any of the details of how they did it . Yes it was still compression ignition but other than that when we were both pulling 129,000 lbs he wouldn't even slow down on Scipio pass on I15 so. of Nephi. We weren't otr trucks we were hauling cement powder around the state so the fuel stops were always the same .. the tanks were mounted behind the day cab where the sleeper usually sets, stacked 3 or 4 high .

 

[mesha]

IMO CNG is a great set up. All questar gas fleet vehicles run them. I use to run CNG on my tow rig 98 chev 2500/454. It was not a dedicated CNG so i had the option to switch from gas or CNG with the flip of a switch. It was an old set up basically a fog kit. Witch gave me about 30% power loss on CNG. Utah will give you a tax rebate of max $2500 for converting to an alternate fuel. It was a great set up and I miss the savings, 63 cents a gallon. It was cheaper for me to drive my 454 on CNG than my wifes altima!! If you figure gas is roughly 3 times the price of gasoline. My truck got 10 miles to the gallon. So it was basically like getting 30 miles to the gallon with a big block. Now the neagative! 1-The tanks are huge I ran (3) 7.2 gal tanks mounted to the flatbed. Witch didn't give a lot of room for cargo. 2-Fuel stations are not very common. 3- Fill up takes a while at the compressor stations (2500psi if memory serves) 4- Finding parts isn't as easy as running up the road to autozone. Just my .02 thought I mite throw it in the mix.

I now have this 454 truck CNG truck thanks man. I have never been happier with the purchase of a truck. I drive wherever I want and cost doesn't bother me. .63 cent a gallon is the best. I do feel a loss of power, but I just flip the switch and off I go. I still haven't changed the oil on the truck. I have had a few problems because it is an older truck. I was driving a suburban w/350 sb. I got around 12 miles to the gallon. I spent around 150-200 month in gas now I spend about 40. I can tow my jeep to moab and back for roughly 40 bucks. I fill up here and in price then when I get to price and here again. I wish the availabilty was better. I wish the tanks were smaller. I get about 25 gallons in the winter and about 18 or 19 in summer. I can go 200-250 between fillups and still have the normal gas if I need it. Last time I filled up it was 14 bucks.
I sold my other car and we are going to buy another CNG. I still haven't figured out how to get the tax credit though. It is way more expensive to convert than LPG. The tanks are high pressure and that scares some people, but not to fear. They are significantly more safe than gasoline tanks. I can't remember the website, but they do distructive testing on some CNG tanks and it is crazy what they are capable of.
If I where converting an old scout it would be LPG because I am lazy and cheap. If I where buying a different car that had already been converted it would be CNG.

 

[NoTrax]

Natural gas is 90% methane, and its non toxic! the other 10% is Propane, Ethane, Pentane, Butane, and some nitrogen!

Ignition temp is 1100-1200 Fahrenheit, Propane is 876 Fahrenheit!!

There is your nerd update from your local RMG tech!

 

[StrobeNGH]

Natural gas is 90% methane, and its non toxic! the other 10% is Propane, Ethane, Pentane, Butane, and some nitrogen!

Ignition temp is 1100-1200 Fahrenheit, Propane is 876 Fahrenheit!!

There is your nerd update from your local RMG tech!

There are times when I feel like I'm 90% methane . . .

Lots of great information guys, keep it up!!!


Anyone have any estimates of converting to CNG?