Welcome to the North American Subaru Impreza Owners Club Wednesday July 30, 2014
Home Forums WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Here you can view your subscribed threads, work with private messages and edit your profile and preferences Home Registration is free! Visit the NASIOC Store NASIOC Rules Search Find other members Frequently Asked Questions Calendar Archive NASIOC Upgrade Garage Logout
Go Back   NASIOC > NASIOC General > News & Rumors > Non-Subaru News & Rumors

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.
* Registered users of the site do not see these ads.
Reply
 
Thread Tools Display Modes
Old 11-09-2012, 10:20 AM   #1
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

OMGHi2U 2012 Ram 2500 CNG

2012 Ram 2500 CNG




Back in 2011 Chrysler divulged that they were looking at applications of CNG for their North American market offerings, with a target date of 2017. Well, Fiat/Chrysler is shipping their first for-Americans CNG vehicle now, five years early. (NB: Chrysler, pre-Fiat offered CNG vehicles in the past including Ram vans and minivans, but not since 2003 or so.)

Quote:
Originally Posted by Chrysler
The 2012 Ram 2500 CNG is the only OEM-built compressed natural gas-powered pickup truck in North America.

It is actually a bi-fuel vehicle that uses compressed natural gas as its primary fuel source, but automatically switches to gasoline when the CNG tanks are emptied. In use, the Ram CNG transitions from one fuel to the other with little discernible difference in operation or capability.

CNG-powered trucks offer cost and emissions benefits, using an abundant, domestically sourced fuel, which reduces America’s dependence on foreign oil. CNG lessens the environmental impact of greenhouse gas and reduces smog-producing pollutants up to 90 percent.

In vehicles, CNG achieves nearly identical mileage figures as unleaded regular gasoline.
Note the first line about the only "OEM-built" offering. Ford/Westport and GM/IMPCO offer 3rd party CNG bi-fuel conversions on their 3/4 ton pickups that one can order through their dealers. In contrast, Ram's offering is done all in house (Saltillo, Mexico), for better or worse, with the benefit being that it's serviceable by any Ram dealer.

Key stats, in my opinion:

- Available for sale both to fleet customers and retail customers alike (initially was fleet-only)
- $11k for the CNG conversion option, which is only available on Ram 2500 Crew Cab 8' bed 4x4 models in the ST and SLT trims. In other words, this is a very, very long truck: 260"!
- 18.2 gasoline gallon equivalents of CNG stored in the two 3600 psi filling pressure steel tanks nestled up in the front part of that long bed, with either 8 or 35 gallons of gasoline proper stored in the regular gas tank as well. (I leave it as an exercise for the reader to figure out total range between the two fuel sources.)
- ~12% power loss and 10% torque loss when running on CNG with unchanged mileage on either fuel
- The CNG conversion adds about 730 lbs in total. Since GVWR is unchanged at 8,800 lbs payload dips by that much: 1,420 or 1,580 lbs, respectively, for a base SLT or ST truck. Check off some options and a 7,500 lb curb weight is realistic, which implies that actual payload capacity is more like 1,300 lbs if one respects the GVWR.
- Towing capacity is a bit lower, too, per Ram: between 7,450 and 7,650 lbs based off of a lowered GCWR of 15,000
- Only 4' 8" of that 8' bed is usable after accounting for the CNG tanks and their metal enclosure, which is at least mitigated a bit by the tanks' steel enclosure that can bear an evenly distributed 1,000 lbs, iirc

Update: Alternate stats based on the FGAWR (5,200), RGAWR (6,010), and GCWR (15,000 per this source) rather than what Ram publishes (in other words, ignoring the GVWR):

- based on the axle ratings one should be able carry five 200 lb passengers in the cabin + over a ton in the bed
- towing a 7,000 lb trailer off a weight distributing receiver hitch would also be possible with a light passenger load: the tongue weight would be well within the axle limits, load rating 120+ tires will still be safe and legal, and there'd still be some headroom under the GCWR (15,000 GCWR - 7,000 lb trailer - 7,500 curb weight - 200 lb driver is non-negative).

Does Ram recommend exceeding the GVWR of 8,800? No. Is their recommendation legally binding? No. Only the tire load ratings, GCWR, FGAWR, and RGAWR matter in the eyes of the law, as far as I can tell, and the rear axle has a literal ton (and change) of extra capacity as it sits from the factory.

Sources:

* Registered users of the site do not see these ads.

Last edited by shikataganai; 11-11-2012 at 09:29 PM.
shikataganai is offline   Reply With Quote
Old 11-09-2012, 10:28 AM   #2
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

So the next logical question that one should ask is "Why the hell should I care about a weird CNG capable giant HD truck?"

Well, here's your answer:



Prices on the map are per GGE of CNG at public fueling stations. Yes, Virginia, that's between 1/3 to 2/3rd of the price of gasoline.

What's more, fleets and even homeowners can fuel up at home (see post #18 in this thread), electric car-style. This home-refueling option makes it attractive to people like me looking for a hypothetical bugout vehicle, too: Free from the gasoline grid if the NG is flowing, and can run on gasoline if it's not available.

If you still need more convincing, then deathinacan provides this list of benefits:

Quote:
advantages -

- domestically produced fuel supply
- 100+ years of domestic supplies (of known shale gas deposits)
- alternate natural gas fuel sources are 'replenishable' ie: methane farms, garbage dumps, septic systems with high methane, etc.
- besides high pressure delivery lines and storage cylinders, a conversion requires very little modification to the OEM components of conventional vehicles.
- reduced greenhouse gas emissions
- very little change to range, performance ( on newer vehicle conversions )
My opinion is that for high-mileage fleet vehicles this is a no-brainer if there's public CNG fueling in the area and the payload restrictions aren't too onerous for the given application.

Last edited by shikataganai; 11-09-2012 at 10:37 AM.
shikataganai is offline   Reply With Quote
Old 11-09-2012, 10:55 AM   #3
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Provided one is willing to disregard Ram's published 8,800 lb GVWR and go by the FGAWR and RGAWR instead, then it could be a useful truck. If you wanted to plow some driveways and roads, you could mount up a 8' 2" Boss Power-V XT and still have some headroom on the FGAWR, and with about 2,700 lbs of headroom between an unladen truck and the RGAWR there'd be plenty of payload left for ballast/counterweight above/behind the rear axle. Hell, put it all behind the rear axle as a counterweight and that'd clear up even more headroom beneath the FGAWR, allowing one to carry some passengers, too.

In any case, the point is that it'd work… as long as you disregard the GVWR. (One could stay "GVWR safe", as it were, by specing a smaller plow, only the driver, and a small amount of counterweight.)





Yes, this is how I spend my free time... Anyway, for more on CNG vehicles in particular see this thread from our very own OT: http://forums.nasioc.com/forums/show...php?p=38420360

Last edited by shikataganai; 11-11-2012 at 09:49 PM. Reason: Updated to disregard GVWR
shikataganai is offline   Reply With Quote
Old 11-09-2012, 10:57 AM   #4
SCRAPPYDO
Scooby Guru
 
Member#: 873
Join Date: Feb 2000
Chapter/Region: TXIC
Location: Just outside of Houston TX
Vehicle:
2013 F150 King Ranch
Datsun 71 240Z & 68 2000

Default

The natural gas coming out of your house is just about 5 psi. You would need a pumping station of some kind. I think this would be smarter if they just made the whole vehicle CNG and srcrew the normal gas all together. That way they could least free up some space for the huge tanks.

Also, that is possibly the most inelegant design I have ever seen. Seems this could be packaged better and lighter and smaller.
SCRAPPYDO is offline   Reply With Quote
Old 11-09-2012, 11:17 AM   #5
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by SCRAPPYDO View Post
The natural gas coming out of your house is just about 5 psi. You would need a pumping station of some kind.
That's what a vehicle refueling appliance like the Fuelmaker lineup is for, to compress the fuel to 3,600 psi: http://www.brcfuelmaker.it/eng/flotte/fmq.asp?click=no . Home refueling is certainly not a cheap option, and the Fuelmakers are far more expensive than the EVSE necessary for home charging of EVs...

Example for a good-sized unit for home use would be a Fuelmaker FMQ-2-36. About $9,000 new + installation. Refuels at just under 1 gge/hr, drawing 1.9 kW to power its compressor.

Quote:
Originally Posted by SCRAPPYDO View Post
I think this would be smarter if they just made the whole vehicle CNG and srcrew the normal gas all together. That way they could least free up some space for the huge tanks.

Also, that is possibly the most inelegant design I have ever seen. Seems this could be packaged better and lighter and smaller.
It's admittedly a completely different market segment but Honda made the choice to make their Civic Natural Gas a dedicated CNG-only vehicle. They used a Type 4 (composite over plastic liner, so lighter) tank and put it in the trunk. Schematic is for the GX, the last gen version pre-name change:



I'd never consider a dedicated CNG vehicle, though. It'd be like having an EV only with much scarcer public recharging refueling infrastructure, totally tethered to the refueling stations or one's home if one had a VRA.

http://www.afdc.energy.gov/locator/stations/ has a map of what's out there in terms of alt fuel infrastructure nationwide.
shikataganai is offline   Reply With Quote
Old 11-09-2012, 11:44 AM   #6
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by SCRAPPYDO View Post
Also, that is possibly the most inelegant design I have ever seen. Seems this could be packaged better and lighter and smaller.
Also relevant is the (3rd party converted) competition, which are just as ugly imo:


Ford/Westport conversion. Ignore the stickers, but instead note the CNG tank enclosure behind the cab.


At least Ram had the decency to not go with diamond plate as did GM/IMPCO.
shikataganai is offline   Reply With Quote
Old 11-10-2012, 01:03 AM   #7
White out
Scooby Guru
 
Member#: 46277
Join Date: Oct 2003
Chapter/Region: SCIC
Location: Michigan
Vehicle:
** Ring Time of
7:43.5

Default

why not modify tanks to fit under the body?
White out is offline   Reply With Quote
Old 11-10-2012, 08:00 AM   #8
sxotty
Scooby Specialist
 
Member#: 95600
Join Date: Sep 2005
Location: Pittsburgh
Vehicle:
2003 WRX wagon
Silver

Default

Yay a truck that you cannot use the bed of... That is why everyone wants a truck right? Anyway seriously if it makes people happy fine they can buy what they want. BTW didn't honda discontinue the phill station for home owners of CNG vehicles?
sxotty is offline   Reply With Quote
Old 11-10-2012, 08:33 AM   #9
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by White out
why not modify tanks to fit under the body?
Possible. Have to shield them down there and harder to get the GGEs desired due to packaging + long cylindrical shape of tanks. Example: WorldCNG can stuff 9.2 GGE of tanks under a Yukon/Tahoe. Compare that to the 18.2 GGE in the bed-stealing Ram in the OP.

Quote:
Originally Posted by sxotty
Yay a truck that you cannot use the bed of... That is why everyone wants a truck right? Anyway seriously if it makes people happy fine they can buy what they want. BTW didn't honda discontinue the phill station for home owners of CNG vehicles?
Fuelmaker, maker of the Phill and larger VRAs alike, went broke and was snapped up by an Italian company. Now they are BRC Fuelmaker, thus the domain name: http://www.brcfuelmaker.it/eng/flotte/fmq.asp .As a side note, the Phill itself makes less sense than the larger VRAs like the FMQ-2-36: http://cngchat.com/forum/showthread....assed-on-Phill

As for the bed length issue: not such a big deal when you consider the restricted payload. Carry people or dense cargo. Pick one.
shikataganai is offline   Reply With Quote
Old 11-10-2012, 09:01 AM   #10
daveyboy
Scooby Specialist
 
Member#: 35419
Join Date: Apr 2003
Default

People worry waaaaayyyyy too much about GVWR from a realistic standpoint.

My family is/was in logging/ranching/construction and I have seen pickups "overloaded" on a constant basis and the vehicles easily lasting 100K miles with no major problems.

Just make sure it has proper tires (that should be your primary concern) and some airbags/timbrens if you are really gonna work it. Oh, and remember you are driving a pickup, not a sports car.

I wouldn't hesitate to throw a ton of weight (literally) in this pickup....
daveyboy is offline   Reply With Quote
Old 11-10-2012, 09:50 AM   #11
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Exceeding GVWR probably would work out 99% of the time, sure, but if you get pulled over by a knowledgable cop or, worse, get in an accident and your insurance company discovers out you (and your vehicle, too! <cue rimshot>) were overweight then it could be much worse, no?

About the worst case that could happen is illustrated in this possibly apocryphal thread: http://www.glamisdunes.com/invision/...howtopic=24262

Quote:
Well, after almost a year has passed since my buddy lost control of his FS3000 toy hauler being pulled by his F-250 coming down Sierra pass. He had sway bars and bags. The trailer swayed somehow and took over the control of his tow rig. He ended up smashing into another vehicle and the passenger in the other was killed and the driver injured.

The highway patrol cited him for hauling the trailer with a tow vehicle that was not rated for the weights of the trailer even though he was not too loaded up. The injured sued him big time, the insurance company disowned him due to the fact that he was improperly rigged and was "using his vehicle for purposes not intended by the manufacturer" even though they insured both vehicles.

He is awaiting trial for manslaughter, lost a civil suit for 1.2 million dollars, of which he was able to get 300,000 dollars from his insurances company sold his home, toys and vacation property to pay for it.

His wife divorced him and he is probably going to do some time.

Bottom line is the man is broke, lost his wife, affected PERMANENTLY the life of another man, and killed a woman all because he didn't want to spend another few grand for the right sized tow vehicle.

Moral of this lesson: BE WARNED! You idiots out there that know you are over limits or running too small size tow rigs, PRAY you never get in an accident!
shikataganai is offline   Reply With Quote
Old 11-10-2012, 10:03 AM   #12
Masterauto
Scooby Specialist
 
Member#: 198376
Join Date: Dec 2008
Location: Delaware
Vehicle:
X5D Subaru BRZ
Nissan GT-R

Default

CNG/LNG and propane are widely used overseas in cars and even large diesel trucks. Over 90% of cabs in Bangkok run on it and the city is larger and has more cabs than Ny.They tell me it pops fine in compression ignition trucks. Of course almost 100% of equipment like forklifts that are used indoors use propane as burns total clean.As I travel alot I noticed even motorcycles in China use it.
Perhaps natural gas vehicles should have been pushed instead of the failing electric ones no one buys. We could have been energy independent by now.
Masterauto is offline   Reply With Quote
Old 11-10-2012, 10:07 AM   #13
Masterauto
Scooby Specialist
 
Member#: 198376
Join Date: Dec 2008
Location: Delaware
Vehicle:
X5D Subaru BRZ
Nissan GT-R

Default

Quote:
Originally Posted by sxotty View Post
Yay a truck that you cannot use the bed of... That is why everyone wants a truck right? Anyway seriously if it makes people happy fine they can buy what they want. BTW didn't honda discontinue the phill station for home owners of CNG vehicles?
No enough usable bed or payload, think diesel option better.
As for Honda CNG the major fail is no multi fuel capable. If they put in a gas tank also you would be assured of ez access to fuel anywhere. a small 6gal gas tank would assure 200 mile range if no CNG available.
BTW any carburetor equipped vehicle can be cheaply converted to multi fuel and is very popular on West coast Canada. Mounting the CNG tanks atop cab under a fiberglass aero cover keeps the bed usable.
Masterauto is offline   Reply With Quote
Old 11-10-2012, 10:30 AM   #14
sxotty
Scooby Specialist
 
Member#: 95600
Join Date: Sep 2005
Location: Pittsburgh
Vehicle:
2003 WRX wagon
Silver

Default

That would raise the center of gravity a lot though. I have to think if they did a real design they could manage like honda to get it down and out of the way. Why can't they stick it between the frame rails. Seriously look gasoline is very energy dense and you don't need a ridiculous high pressure tank. Put the CNG where the gas tank is an a much smaller gas tank somewhere else. There are gas stations all over. You don't need the range on gas that most vehicles have. Then a person can use CNG, the bed, and gas if they need it.
sxotty is offline   Reply With Quote
Old 11-10-2012, 11:29 AM   #15
bal00
Scooby Specialist
 
Member#: 54772
Join Date: Feb 2004
Default

What a poor conversion.

$11k, only available on the monstertruck model and it still makes the bed useless...


For comparison:















CNG is a $3600 option on the Zafira, it has a 330 mile range on CNG (+120 miles or so on gasoline), makes slightly more power than the equivalent gasoline model, keeps the same payload capacity and it has exactly the same interior, with all the CNG-related stuff hidden underneath the car. Zero loss of cargo space.
bal00 is offline   Reply With Quote
Old 11-10-2012, 11:44 AM   #16
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Petition GM to bring that to these shores, then. The point is that it's not available. The Ram, its HD Big 3 brethren, and the Civic NG are. Such are the choices we have, and because of the comparatively sucky choices we have a limited public distribution system. Chicken and egg problem.

EVs solve that particular problem because the home charging equipment is much cheaper than NG VRAs and the public charging infrastructure is already better and improving monthly.
shikataganai is offline   Reply With Quote
Old 11-10-2012, 09:17 PM   #17
bal00
Scooby Specialist
 
Member#: 54772
Join Date: Feb 2004
Default

Quote:
Originally Posted by shikataganai View Post
Petition GM to bring that to these shores, then. The point is that it's not available.
I get that, but when you consider how much better integrated and cheaper the CNG system is, the Ram conversion looks like a lazy amateur job in comparison. What I'm saying is, Dodge should have done better than filling the bed with huge tanks and then charging an arm and a leg for it.

I just don't see the point in such a half-assed conversion. If you tow a lot, you're still better off with the diesel, and if you need to carry a lot of stuff, then this isn't the right vehicle either.
bal00 is offline   Reply With Quote
Old 11-10-2012, 10:07 PM   #18
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Target market that I imagine: fleet vehicles for oil and gas companies in the Rockies and Midwest. Cheap CNG from the company well, as it were, high mileage driven each year, and a need for 4x4s to get out on the range. They wouldn't need to carry heavy equipment to the field necessarily, as such equipment would require much bigger trucks yet. I think it totally makes sense for this kind of oilfield transport scenario.

I calculate NG direct cost plus VRA compressor energy cost of 8.6 cents per mile at relatively high Seattle residential NG prices so if the form factor and payload restrictions fit the bill it's certainly cheaper to run than gas or diesel vehicles for high mileage fleets that need to move people off road.

With regard to pricing, they're just matching the pricing structures of the 3rd party Ford and GMC conversions. No competition and surely little volume so no real motive to drop the price.
shikataganai is offline   Reply With Quote
Old 11-10-2012, 11:26 PM   #19
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by daveyboy
People worry waaaaayyyyy too much about GVWR from a realistic standpoint.

My family is/was in logging/ranching/construction and I have seen pickups "overloaded" on a constant basis and the vehicles easily lasting 100K miles with no major problems.

Just make sure it has proper tires (that should be your primary concern) and some airbags/timbrens if you are really gonna work it. Oh, and remember you are driving a pickup, not a sports car.

I wouldn't hesitate to throw a ton of weight (literally) in this pickup....
Quote:
Originally Posted by shikataganai
Exceeding GVWR probably would work out 99% of the time, sure, but if you get pulled over by a knowledgable cop or, worse, get in an accident and your insurance company discovers out you (and your vehicle, too! <cue rimshot>) were overweight then it could be much worse, no?
So my curiosity was piqued by daveyboy's claims, and I will partially concede the point: Apparently it's only in a limited number of states and provinces that exceeding GVWR is illegal. BC is one such province.

Exceeding the Federal bridge weight axle limits (20k for single axle, so high enough to not be relevant to pickups of any kind) or exceeding the tires' ratings, the FGAWR, or the RGAWR is a bigger deal that does seem to be illegal in most states. If you stick to your tires' load rating and make sure you're not overweight at each axle you should be good... at least until you get slapped with a civil suit, where all bets are off.

:themoreyouknow:

Last edited by shikataganai; 11-10-2012 at 11:49 PM.
shikataganai is offline   Reply With Quote
Old 11-30-2012, 11:59 AM   #20
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by bal00 View Post
I just don't see the point in such a half-assed conversion. If you tow a lot, you're still better off with the diesel, and if you need to carry a lot of stuff, then this isn't the right vehicle either.
Semi-necro-bump (body is still warm, perhaps? ) as I figured out a better alternative for those who want CNG bi-fuel capability in a truck that does truck-stuff (payload + towing capacity) much more respectably:



There exist multiple companies doing Ford-approved CNG dedicated and bi-fuel conversions on Ford Super Duty trucks. The plus, relative to the Ram in the OP, is that said conversion companies will convert any variety of (6.2L gas-prior-to-conversion) F-250 or F-350 you throw at them.

Regular cab SRW F-250 with tall highway gears? Sure. Crew cab long bed DRW F-350 with 4.30 gears? No problem.

Said F-350, set up as above, would have a GCWR of 22k, a GVWR of 14k, and would weigh around 7k itself. Even accounting for a few hundred pounds of CNG conversion detritus + tanks (Westport quotes 248 lbs for their whole system, for instance) that'd still leave plenty of capability in store: Ignoring the CNG system's weight such a vehicle would have towing capacity of 15k and a payload inclusive of passengers of around 7k.

Not bad.

What's more, BAF Technologies, one of the many CNG upfitters out there, will set up such a truck with 10 GGE of CNG under the bed, where such tanks should logically live. (If you want more they'll stick an additional 20 GGE in the front of the bed, a la Ram.)
shikataganai is offline   Reply With Quote
Old 03-16-2013, 10:46 PM   #21
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by bal00 View Post
I just don't see the point in such a half-assed conversion.
Quote:
Originally Posted by shikataganai View Post
I calculate NG direct cost plus VRA compressor energy cost of 8.6 cents per mile at relatively high Seattle residential NG prices so if the form factor and payload restrictions fit the bill it's certainly cheaper to run than gas or diesel vehicles for high mileage fleets that need to move people off road.
Saturday night cost estimation time, since I already did the math for another thread, the baby is sleeping peacefully between feedings, and I think the numbers are actually somewhat interesting/surprising:

Full assumptions in this post, for the morbidly curious, with the high points being a reasonable guess at CNG system depreciation, $4/gallon gasoline, Seattle residential NG prices as per the quoted post above, and home refueling via a bought-used VRA that doesn't depreciate much after being initially installed. Whew. That's a sentence and a half. Anyway, the point is that I think the assumptions are reasonable.

Given the above then the breakeven point for a Ram CNG relative to a non-CNG Ram lies somewhere around 64,000 miles and 5 years. Note that this breakeven point assumes one places a value of $0 on the intangible aspects of having an alt fuel vehicle, namely environmental somewhat-friendliness, domestic sourced fuel/not supporting dictators overseas, convenience of home refueling, and the lack of being tied to the gasoline grid.

As for me, I actually place a pretty high value on those intangible aspects, as evidenced by my prior electric bike shenanigans, my wife's current Prius, and her EV-in-next-year plans. For ****s and giggles, if we assign those intangibles a value-to-me of just over $100/month then the CNG Ram pays for itself in 3 years and 36,000 miles.



(The real elephant in the closet underlying the above calculations' assumptions is whether I'd be interested at all in a non-CNG Ram 2500. The answer to that would be no. But since I'd rock a Land Cruiser, which is more or less in the same ballpark cost and MPG-wise, I'll let the elephant sidle past without further mention.)

Last edited by shikataganai; 03-16-2013 at 11:49 PM.
shikataganai is offline   Reply With Quote
Old 03-17-2013, 07:47 AM   #22
sxotty
Scooby Specialist
 
Member#: 95600
Join Date: Sep 2005
Location: Pittsburgh
Vehicle:
2003 WRX wagon
Silver

Default

Shika CNG vehicles are not as good for the environment as many seem to think. Methane is a far more potent GHG than CO2 and there will be plenty of methane leaking to the environment if we have tons of CNG vehicles running around. They are better for the immediate area they operate in though. So local effects are lessened global effects see little change. You also need to include the costs of having the Ram including lessened cargo and towing capacity in your calculations.
sxotty is offline   Reply With Quote
Old 03-17-2013, 11:17 AM   #23
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by sxotty View Post
You also need to include the costs of having the Ram including lessened cargo and towing capacity in your calculations.
I have no idea how to account for the lessened cargo and towing capacity. If it's sufficient then it's sufficient, and if it wasn't the hypothetical buyer wouldn't have purchased it?

Quote:
Originally Posted by sxotty View Post
Shika CNG vehicles are not as good for the environment as many seem to think.
Anyway, it's true that CNG is no panacea with regard to the environment, but it is nonetheless represents a non-negligible improvement while also being cheap and nearly entirely domestically sourced. Per this arbitrarily picked analysis, CNG vehicles offer "an 18%-19% reduction in the overall life cycle environmental impact" relative to gasoline.

So there is a global benefit, albeit a small one. For the diesel proponents, note that they concluded "mineral diesel and petrol are equivalent (within confidence limits) regarding total life cycle environmental impact".

The leading technology in their analysis is electric, of course:

Quote:
In those vehicle classes where available, the use of battery electric vehicles consistently result in the lowest overall environmental impact[,] always the case if renewable energy is used for recharging. In the best case, as compared to a petrol baseline, the overall environmental impact is reduced by over 70%.
The catch is in the phrase is at the start, "in those vehicle classes where available". Large, 4x4 BEVs with quick recharging ability akin to refueling a liquid or gaseous fuel vehicle are conspicuously unavailable on the market, and even I don't expect that to change any time soon.
shikataganai is offline   Reply With Quote
Old 03-17-2013, 04:58 PM   #24
sxotty
Scooby Specialist
 
Member#: 95600
Join Date: Sep 2005
Location: Pittsburgh
Vehicle:
2003 WRX wagon
Silver

Default

Shika the studies I have seen say it is better to burn natural gas, make electricity, charge a car, and drive.

Than to burn gas in a car and drive.

That was because the methane emissions from a huge number of mobile sources are actually quite problematic. As far as vehicle capability there are actually econometrics papers and consumer choice models etc... that give valuation to things such as towing capacity, cargo capacity, interior room, etc... I am not saying these evaluations are good, or believable, but it is a non-negligible factor when comparing vehicles. So for example losing the middle seat in the Volt is problematic. Just like losing a lot of the bed of the truck. A person still might buy the vehicle and then have to rent another vehicle to accomplish certain tasks. Or in the case of a middle seat they might buy the vehicle, then sell it to buy another one. That is still a cost to the consumer and not something they appreciate.
sxotty is offline   Reply With Quote
Old 03-17-2013, 05:41 PM   #25
shikataganai
Scooby Specialist
 
Member#: 92634
Join Date: Aug 2005
Chapter/Region: RMIC
Vehicle:
2007 Land Cruiser
2013 LEAF

Default

Quote:
Originally Posted by sxotty View Post
Shika the studies I have seen say it is better to burn natural gas, make electricity, charge a car, and drive.

Than to burn gas in a car and drive.
I don't dispute this at all. I'm just putting forth CNG, especially bi-fuel vehicles, as an alternative for the form factors for which EVs aren't practical, aren't offered, or simply don't make sense.

On the other hand, the marginal improvement of only "an 18%-19% reduction in the overall life cycle environmental impact" is somewhat disappointing, as it is well within the variation that one would expect in driving habits (miles driven), particular choice of vehicle, etc.
shikataganai is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -4. The time now is 08:13 AM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2014 Axivo Inc.
Copyright ©1999 - 2014, North American Subaru Impreza Owners Club, Inc.