CNG vehicles

airguy

airguy

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airguy
Throwing some bait into the water for opinions on this one, experience with different brands/systems etc.

My position - I live in a rural area and commute to the city daily for work, about 90 miles roundtrip each day plus any running around for errands. I drive past a CNG fueling station twice a day every day, so I'm one of the lucky few that have easy access to the fueling stations. The cost of gas here is about $3.50 a gallon, the cost of CNG is $1.50 per gallon equivalent. With the added cost of the bifuel option (gasoline and CNG) on the new vehicles being sold today, the breakeven point is about 100,000 miles. The last two pickups I sold at 179k and 187k, and my current one is at 271k and still running strong, so I have no doubt that I will keep a vehicle long enough to pay off the CNG option cost. I'm aware that CNG only gives about 75% of the horsepower that gasoline does, but I don't have any need for racing up and down the road at my age and only occasionally pull relatively light trailers. I'm also fully aware of the storage issues with the tank and it's available fuel quantity, and I'm ok with that tradeoff since I have such easy access to the fuel. The only new CNG trucks (and yes, I need a pickup, either crewcab or supercab) are 3/4 ton, available from Chevy, Dodge, and Ford. Prices are roughly comparable but warranty and service vary. I'm seriously looking at buying one of the them in about 6 months, I'm just trying to compare them and figure out which I prefer. I've always been a Chevy guy but I'm not married to them.

Any experiences on this that someone would like to share?
 
In New York City there were a large number of taxis (Ford Crown Vics) that were CNG. They seemed to have good reliability, and worked because they had access to CNG refueling stations (like you). I would feel comfortable buying one if I used it for local driving and had a refueling station nearby.

The only special considerations I'd have are what happens if that station closes (possible) and what happens when you sell it? If you go 200-300k on a vehicle then resale is probably not a major consideration.

I'd probably buy the Ford truck just because I like Ford better as a company and they have good experience with their V8s on CNG.
 
I ran a turbo Mazda PU for years... When I moved to Orlando I switched it to straight propane.. Simple conversion. Impco has great products and they work well and reasonably priced,,, Seems I was able to switch over to Propane for a few hundred bucks including the tank and high pressure hose... http://www.impco.ws/


Gas back then was around a buck.. Propane was .30 or so... Truck ran better and I turned up the wastegate 5 more PSI for added thrills...

If I was doing this today,,,,, And I am really considering it too,,, I would buy a old truck and convert it to straight CNG... The duel fuel route gets damn expensive , damn fast....

The most adventagous reason is if you have NG at your house, you can put in a "fueling station" in your garage and fill up at home... No road tax;)...In the coming years and the deficit and massive shortfall of guvmint funding you will see insane increases in fuel taxes..:yikes:....
 
N801BH said:
The most adventagous reason is if you have NG at your house, you can put in a "fueling station" in your garage and fill up at home... No road tax;)...
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Valid consideration, but I don't have natural gas at home for that. The cost of the home refueling compressor plus the electricity to run it add about 40,000 miles to the breakeven cost of the conversion also - it's not all milk and cookies.
 
My brother operates a commercial truck powered with CNG. The numbers work very well. The only issue is that not all dealerships of the manufacturer have techs on staff who are certified to work on the CNG side of the system.
 
airguy said:
Valid consideration, but I don't have natural gas at home for that. The cost of the home refueling compressor plus the electricity to run it add about 40,000 miles to the breakeven cost of the conversion also - it's not all milk and cookies.
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Agreed to that.......

A local guy just priced a CNG conversion kit for his new 2012 Chevy PU... It was over 11 grand and added 900 lbs to the truck, and reduced his bed size 60%.... In my mind that is a 100% deal breaker...

I am just now pricing my home brewed system and the costs are fractions of that figure... I am in the same boat as you though as I have no NG here at home,,,,,,, and the local guv has been tallkng about installing a CNG fill station somewhere in town.. But so far No Joy...
 
So now you got me thinking, as we have natural gas at home and it's cheap. What's involved in a home brew conversion? I could use an excuse to buy a Cadillac. :D
 
Ted DuPuis said:
So now you got me thinking, as we have natural gas at home and it's cheap. What's involved in a home brew conversion? I could use an excuse to buy a Cadillac. :D
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And I could fly back there and help you install the fueling station and the conversion kit on the Caddy... We would either have a TON of fun and make a billion on the idea.. or get arrested for having too much fun without a permit...:wink2::yes: :D
 
Are there conversion kits out there that can use the existing computer? That sounds interesting to me. Any links?
 
Ted DuPuis said:
Are there conversion kits out there that can use the existing computer? That sounds interesting to me. Any links?
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I don't DO computers...:no::nonod:..

I am a carb, coil and distributor kinda guy...:yes:;)...

I will let ya know if I stuble across some info though..:yesnod:
 
I'll do some Googling. Could be a good option for an alternate daily driver. I have been wanting to get another Caddy and put a big block in. :D

Or for that matter I'd be fine with converting the Mitsubishi if it had the anti-knock properties necessary to support my horsepower levels.
 
N801BH said:
I run ADI on all my turbo stuff.... But.. he won't need much as Propane and CNG is about 112 octane..
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That would work out well. Right now I limit myself to 15 psi on 93. 20-25 sounds like fun.

I'll do some serious looking when I get home. I especially like the home refilling option. Back before we moved here we did mostly long trips, but we haven't done a road trip since moving here and don't plan on it.
 
back in the good old days of carburetors and distributors with points, my brother-in-law did a propane conversion to a Chevy 2500 with 350 V8. As I recall, the entire conversion consisted of an in-bed propane tank (his dad had a propane distributorship so tank was "found" in the yard - free) hoses, switches and valves and some kind of propane injector unit that bolted up on top of the carb (or was it between the carb and manifold? don't recall exactly now). Very simple install.
I believe normal operating procedure was to start on gasoline, run until warmed up then switch to propane.
 
airguy said:
(and yes, I need a pickup, either crewcab or supercab)
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Do you have to commute in the truck? Just asking. I need to have a truck, but if I drove to work (I'm a telecommuter) I wouldn't have to commute in it.
 
DaleB said:
Do you have to commute in the truck? Just asking. I need to have a truck, but if I drove to work (I'm a telecommuter) I wouldn't have to commute in it.
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I don't have to - but I choose to. The highway I commute on is absolutely cram-packed with oilfield traffic and we have a fatal accident there 2 or 3 times a week. I've personally watched several smaller cars get completely wadded up with zero chance of survivability - I fully intend to be rolling down the road with at least 8,000 pounds of Detroit steel wrapped around me to increase my chances, and that means I'm going to burn some fuel, which is why I'm interested in reducing my fuel costs.
 
airguy said:
I don't have to - but I choose to. The highway I commute on is absolutely cram-packed with oilfield traffic and we have a fatal accident there 2 or 3 times a week. I've personally watched several smaller cars get completely wadded up with zero chance of survivability - I fully intend to be rolling down the road with at least 8,000 pounds of Detroit steel wrapped around me to increase my chances, and that means I'm going to burn some fuel, which is why I'm interested in reducing my fuel costs.
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Move closer to the job? :dunno:
 
Geico266 said:
Move closer to the job? :dunno:
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Nope - I moved AWAY from the job to get the hell outta that city for my sanity and raising a family. I much prefer to commute back and forth rather than deal with living there, there are many advantages in my case to living where I am now and the commute does not even start to outweigh them.
 
So, did a little math for the conversion.

Looks like in-home refuelers can be had for $2-3k each. I did the math and based on current natural gas prices here, it comes out to about $1/gasoline gallon equivalent. Seems that our price for natural gas is higher than others! Where we live, this would be the only option for us as there are no refueling stations within 100+ miles. Still, about a $2.50/gallon savings with current prices at the pump.

There are different conversion options. There's one that looks like it's basically a TBI setup that goes in-line before the throttle body and one that's multi-port and requires that the manifold be drilled out to make room for the nozzles. As you'd expect, the latter is more expensive than the former. They all start off on gasoline and then switch to CNG when the engine gets up to operating temperature since it uses engine coolant to heat the CNG to keep it liquid, and you can manually switch back to gasoline if you want. I don't know what temperature they're looking for from the coolant.

Basically it looks like about $1-2k per vehicle to get converted when you factor in the system and the tank, also depending on the tank size that you want to use.

So, to convert our two vehicles and get the filler, figure somewhere between $4-7k all said and done. At a $2.50/gallon savings and an average of 15 MPG, figure 25,000-42,000 miles for the break even point. For us that would end up being about 18-30 months, then the savings rake in.

Interesting consideration.
 
Accidents like this one back in the '70's and '80's surely didn't help to further the cause of CNG:

SPRINGFIELD, Mo., March 1, 1981— A propane gas explosion destroyed a carwash on a busy city street yesterday, killing one man and injuring at least 15 persons.

Fire Marshal Dan Thurman said a hose on a liquid propane gas tank mounted on a pickup truck was damaged, apparently after becoming entangled on a rotary brush at the carwash. Propane fumes filled the building and ignited seconds later, he said.

The carwash was demolished by the explosion and several nearby businesses were damaged by the ensuing fire. James Brown, 18 years old, of Springfield, an employee at the carwash, was killed. Fifteen persons have been hospitalized with injuries, Mr. Thurman said. Others were thought to have suffered minor injuries.
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I was going to college in Springfield when this happened. It was a bad deal. Damaged every building on a full city block...pretty impressive force.
 
Skylane81E said:
Hmm, not horrible.
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Nope. When I was driving 30k miles/year it would've been a bigger advantage, but I didn't have natural gas at my house and no stations nearby. Plus I did long trips all over. Savings just wouldn't have been significant.

timwinters said:
Accidents like this one back in the '70's and '80's surely didn't help to further the cause of CNG:

I was going to college in Springfield when this happened. It was a bad deal. Damaged every building on a full city block...pretty impressive force.
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That would be the risk. Then again, I haven't heard of issues these days with the more modern conversions.

It's got my interest. Needs more research, but I like that the payoff is there even if we move. Can always take the home refueler with us, and could even remove the conversion kit to put on another vehicle.
 
I don't really want to buy a Mercedes.

Actually, the math only makes sense if you convert your existing vehicles with the number of miles we drive. And it only makes sense to have around a 10 gallon equivalent tank since beyond that price goes up significantly.
 
airguy said:
Nope - I moved AWAY from the job to get the hell outta that city for my sanity and raising a family. I much prefer to commute back and forth rather than deal with living there, there are many advantages in my case to living where I am now and the commute does not even start to outweigh them.
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People who have not seen how things are out there, just cannot imagine how packed your roads are, how many people there are frenetically doing the energy game. I paid $270 for a room night at the La Quinta a few weeks back - and was glad to get it!
 
Back in the day... 25 years ago... dad worked for an Enron predecessor out in the field.. he bought a surplus truck from the company that had been converted to CNG/Bi-fuel. It burns VERY clean... this truck had the engine hour equivalent to 300,000 miles before we parted with it.....

The company used em because they were in the gas business, on a compressor facility, and could fuel up the truck with the product they had on the grounds.

The big limitations appear to be refueling conveniently, having the big tank, and having less fuel density per gallon/pound.... If you have refueling figured out, go for it. CNG is CHEAP right now...
 
After digging through the offerings, it comes down to the Chevy 2500HD or the Ford 250. Prices are similar, Chevy has the better warranty, Ford has the bigger tank as an option (24 gge vs 17).

Probably just going to come down to a test drive in each to see which one I like better. I've always been a Chevy guy but I'm open to options.
 
We rented a new Yukon XL last month. I liked the way it drove. I haven't driven any Ford truck made after 2000, but I loved my 2000 Excursion.

I'd be less concerned about the warranty. The CNG system is pretty simple and I wouldn't worry about it breaking. Bigger tank would be a plus for me, especially figuring the mileage those things would have.

The conversion route so far looks like there's not as much available for my twin-turbo hot rod as my wife's Avalanche, which would be easier all around to convert. But for the financials to add up to a reasonable payoff, both vehicles would need to be converted.
 
CNG vehicles get bashed in hailstorms just as badly as gasoline vehicles!

One thing that surprised me is that I almost pulled into the filling station opposite the rental car return at KSFO then found out it was a natural gas station. There are also many natural gas vehicles in the city itself, especially taxis, etc.
 
Ted DuPuis said:
......The conversion route so far looks like there's not as much available for my twin-turbo hot rod as my wife's Avalanche, which would be easier all around to convert. But for the financials to add up to a reasonable payoff, both vehicles would need to be converted.
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A conversion for the twin turbo needs to be a homebrewed design and it is NOT as difficult as you may believe..... :no::no:.

As for the "start it on gas and switch to CNG" is highly overstated too... My street rod PU started just fine on vapor.. EVERY time.. The issue comes in when you go out and start it and intend to accelerate to 100 MPH in the next 2 minutes.... No engine should be treated like that and the reason the CNG set up doesn't like it is because the step down regulator will ice up until you get the engine jacket water up to around 100 degrees f .....At idle the motor warms up slowly and nicely....
 
N801BH said:
A conversion for the twin turbo needs to be a homebrewed design and it is NOT as difficult as you may believe..... :no::no:.

As for the "start it on gas and switch to CNG" is highly overstated too... My street rod PU started just fine on vapor.. EVERY time.. The issue comes in when you go out and start it and intend to accelerate to 100 MPH in the next 2 minutes.... No engine should be treated like that and the reason the CNG set up doesn't like it is because the step down regulator will ice up until you get the engine jacket water up to around 100 degrees f .....At idle the motor warms up slowly and nicely....
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Yeah, one thing I was also wondering was what the temperature for switch over is. I figured it'd be pretty low, i.e. coolant would reach the temperature fairly quickly. Otherwise the benefit is minimal. Personally I'd want to set up any system to switch to CNG sooner rather than later temperature wise, so ideally I'd be able to play around with that in calibration. Of course I could probably also get around it.

I figured a DIY setup wouldn't be too difficult to do. There are also some setups that look like I could basically double up for the VR4 and have it work just fine. So I think that none of it is insurmountable.

I called the city today to ask about regs and incentives. They got all excited (in a positive way) and I've got a phone meeting with a program manager for the green initiative here (our town is >50% renewable energy right now, and aiming to increase that further). So this might be good timing. Plus, a 450 HP twin turbo car running on CNG would be a good poster for convincing some of the less conventional adopters that there's benefit. :)
 
Being running our old Chevy pick up truck on propane for ever I don't have a CNG station close home but I use a regular propane tank mounted on the bed of the truck, In Argentina were I born they being runing cars on CNG for the last 20 years, I have a regulator under the hood and a solenoid controls wen I switch from gass to CNG I do always start the truck on gass, in winter CNG can be hard to start.

And Ben is right if you don't do it right the regulator would become a ice ball.:yes:
 
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Well, had a good chat with the city. Turns out they're wanting to do this, and my timing is really good since I get to be the guinea pig.

Going to do some research and come up with a proposal over the next week.
 
Ted DuPuis said:
Well, had a good chat with the city. Turns out they're wanting to do this, and my timing is really good since I get to be the guinea pig.

Going to do some research and come up with a proposal over the next week.
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If anyone in the world can pull this off... it is YOU....

Ps... remember to wear as much http://www.cloudninerescueflights.org/ apparel so the masses will donate when they see ya on TV..:yes::)
 
Good idea, Ben. :yes:

We'll see what happens. It sounds exciting. I like the idea of a massive cut in monthly expenses. Means more money to spend on airplanes. :D
 
Another point I made was that we make non-stereotypical candidates, good for marketing to a wider audience. A 450 HP twin turbo daily driver on CNG shows that it's not just for Prius drivers.
 
This is really tempting to me as well...I just need to figure out how to get someone else to pay for it :)
 
You get it off the ground I'd like to see the set up. If I could duel fuel my Dodge it could save some decent money.
 
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