Any thoughts on CNG as sole consumable fuel?

[tachikaze]

I'm many moons away from putting together my own campmobile, but:

http://i.imgur.com/sERDU.png

and

http://www.eia.gov/dnav/ng/hist/n9010us2A.htm

has got me thinking . . .

the major downside is availability:

Alternative Fueling Station Locator

but that will only increase over time I guess.

80 DGE of CNG in twin 3600PSI tanks comes in at 900+ lbs (500 lbs for the fuel and 400+ for the tanks) so there is a weight penalty but I'm attracted to the apparent operating cost savings, one-fuel convenience, fuel security (internal tanks) of CNG.

 

[tachikaze]

hmm, I didn't know Canada CNG prices were so cheap . . .

http://i.imgur.com/EUZnZ.png

 

[haven]

Here's another web page that helps you find alternative fuels in USA. On the San Francisco peninsula where I live, there are three CNG stations close by.
http://www.altfuelprices.com/

Here's a Car and Driver review of the Honda Civic with CNG fuel. http://www.caranddriver.com/reviews/2012-honda-civic-natural-gas-test-review

The CNG Civic gets about the same fuel economy as the Civic with gasoline engine, but the fuel tank size limits range to about 200 miles between fill-ups. The good news is that CNG costs about $2.15 a for the equivalent of energy contained in a gallon of regular gasoline (called the GGE).

 

[tachikaze]

I think my comment would also apply to CNG

Heh, you were apparently running a F250, which only has a two ton payload.

The direction I'm attracted to is full Damnation Alley-scale here with a rig that could make it from LA to Seattle nonstop and/or go off-grid for a month if need be.

I don't want to blow the entire weight budget on CNG tanks but 3 tanks with 120 DGE weigh 1400 lbs with current Type 4 (composites) packaging.

The future does have interesting developments on the weight front, eg:

http://tulsabusiness.com/Main.asp?SectionID=3&SubSectionID=50&ArticleID=54491

The idea of moving away from liquid fuels is interesting to me, as is the apparent ability to install proper household natural gas appliances instead of speciality marine / RV sector stuff.

Medium-duty scale seems to have the weight and space allowance to do this without too much tradeoff.

 

[tachikaze]

That was my experience wanting to travel unfamiliar areas

yeah, that there's only two public CNG fueling stations in all of Oregon -- and nothing between Medford and Tacoma -- is odd.

Also nothing between S Lake Tahoe and SLC (but if you can make it to Utah the $1.50/GGE price is your reward).

Highways 101 and 395 in California are also pretty sparse.

So I guess keeping the diesel tank is an option for conversions:

http://www.greencarcongress.com/2012/03/gmcng-20120305.html

but I need some research on how well conversion engines hold together I guess.

I'm also interested in electric motor drive applications -- for uphill torque assist, downhill braking regenerator, range extending, and perhaps a second drive axle, but that is certainly another topic.

Going military with a CNG microturbine powerpack -> generator -> electric motor system is another idea . . .

http://www.capstoneturbine.com/prodsol/solutions/hev.asp

apparently possible if not particularly . . . pragmatic

 

[taylorRichie]

So there's a filling station around the corner from me ($1.50/gge)... and a 100 series that's been converted to CNG for $13,000 local. When it's converted can you still use gasoline? Does this vary depending on the conversion? WHat kind of MPG equivalents would you expect on a Cruiser(23-35mpg)? What would the real world cost savings be?

Thanks guys...

Richie

 

[charlieaarons]

CNG/LNG will increase market share at first in vehicles that belong to fleets with a central fueling spot, over-the-road trucks that don't stray much from main roads with fueling infrastructure, and in areas (i.e. urban Utah) with CNG infrastructure in place (due to low prices and demand due to local prevalence of private CNG vehicles).
IMHO serious consideration of this for an "expedition" vehicle (i.e. campervan etc.) is grossly premature and would severely limit mobility options. The sine qua non of such a vehicle is its' ability to go many places without much advance planning.

Charlie

 

[Tony LEE]

and a 100 series that's been converted to CNG for $13,000 local

so assuming the same fuel economy, payback will take 13000/(4-1.5) gallons. How many years would it take to use 5200 gallons of fuel. 15mpg, that is 78000 miles not factoring in the opportunity cost of forking out $13000 in the first place.

 

[drkddl]

New to ExPo and been mainly lurking, but finally a thread pops up I can contribute to.

I'm in the oil industry in Oklahoma and have previously owned 2 bi-fuel CNG/gasoline pickups. CNG is indeed catching on and I believe it will become a viable nationwide daily driver alternative to gasoline/diesel/ethanol in the future, but it's not quite there yet, especially for an expedition rig. There are a number of issues

1) Weight, which you've already considered. Those tanks are big and heavy, even if you get the Type 4 Composites. There are some interesting developments on the horizon with Chesapeake's partnership with 3M to use advanced composites in CNG tanks, but that isn't market ready yet.

2) Cost. You're looking at $10,000 plus to convert a gasoline powered rig to CNG without buying tanks. I had a new 24.5GGE Type 4 tank in one of my trucks and it cost over $4,000. For 120GGE, you're going to fork out $20,000+ just on tanks alone. If you get a medium-duty diesel powered rig, the only viable option (IMO) is to find a used CNG Cummins out of a schoolbus or something similar. Also, 120GGE of tank space will mean you'll probably only get 90-100GGE of usable fuel in the tanks due to the pressure differential required to move the gas through the regulator.

3) Availability, which can be managed with proper planning and routing.

4) Dependability. Not of the vehicle, but of the CNG stations themselves. This is something you don't really consider until you actually have a CNG-powered vehicle. At least half the stations I know of have broken down for extended periods at various times. Many stations only offer 3000psi fills (for the older schoolbuses and fleet vehicles from the past 2 decades) which will further diminish your range. Every single station I've been at has occasionally given me such slow fills that I end up leaving before even filling a 21GGE tank. Some stations have inadequate compressors or storage tanks that are too small. Some fleet CNG fill stations are open to the public, but only during daylight hours. I had to skip University of New Mexico's station the day after Christmas because they had it locked up in their fleet yard (which is open when the school isn't closed).

There is a reason dedicated CNG fleets are generally used only locally in conjunction with a privately-owned fill station. You can't depend on the infrastructure if you are running on Empty and it's the only CNG station in the state.

One day CNG will be a great option. It's a cleaner, American-sourced fuel that offers great cost savings and utilizes infrastructure that is already in place in most of the country. For now, I'd hold off.