Just finished my Compressed Natural Gas 1.8 turbo 60 cents a GAL.

[john.jackson9213]

Frankly, a diversity of resources to power our tansportation systems is not a bad thing.
In San Diego, a number of buses use CNG as the primary fuel. Our local wastewater treatment plant uses methane gas from the digesters to run two generators for electricity. They also use a small hydro plant to recover energy from the wastes flowing out to sea at a depth of more than 300 feet.
Personally, need to look at what I pay for CNG delivered to my home. I am not sure that CNG cost 60 cents a gallon in California.
If I remember correctly, diesel has about 6 million BTUs per gallon and 1000 cubic feet of Natural Gas has about 1 million BTUs. So the conversion is around 600 cubif feet of natural gas for 1 gallon of diesel (in terms of BTUs).
Again, I need to check the local costs.

JJ

 

[TurbinePower]

Frankly, a diversity of resources to power our tansportation systems is not a bad thing.
In San Diego, a number of buses use CNG as the primary fuel. Our local wastewater treatment plant uses methane gas from the digesters to run two generators for electricity. They also use a small hydro plant to recover energy from the wastes flowing out to sea at a depth of more than 300 feet.
Personally, need to look at what I pay for CNG delivered to my home. I am not sure that CNG cost 60 cents a gallon in California.
If I remember correctly, diesel has about 6 million BTUs per gallon and 1000 cubic feet of Natural Gas has about 1 million BTUs. So the conversion is around 600 cubif feet of natural gas for 1 gallon of diesel (in terms of BTUs).
Again, I need to check the local costs.

JJ

Um? Try more like 130k BTUs per gallon for diesel. Six million?

Seems like natural gas has a value of 1020 or so BTUs per cubic foot at standard temperature and pressure.

So more like 130 cubic feet at standard temperature and pressure.

 

[brucebanes]

So can you run this in a Diesel engine ?

 

[BKmetz]

If I remember correctly, diesel has about 6 million BTUs per gallon and 1000 cubic feet of Natural Gas has about 1 million BTUs. So the conversion is around 600 cubif feet of natural gas for 1 gallon of diesel (in terms of BTUs).

JJ

The BTU content of methane is very stable at 1000 BTUs per 1 standard cubic foot (scf). A standard cubic foot is defined at 15.6C/60F at sealevel, or 14.7 PSI, 1 Atm, 101.3kpa, etc. The common unit for methane usage is the therm. A therm is 100,000BTUs of energy content. So 100 cubic feet of methane equals 1 therm.

The BTU content of #2 diesel fuel is not as stable. It depends on the crude it was refined from, if it is blended with any lighter fuels like any of the #1 fuel oil derivatives; #1 diesel, #1 fuel oil (kerosene), the temperature of the fuel, etc. My point is there are a lot of variables.

For a general number for comparison, ~130,000BTUs/gallon for #2 is considered average. It can be as much as 5000 BTUs off either way depending if the fuel is blended and how it was refined.

Here is an API gravity table showing BTU content of fuel oils vs temerature.

In order to use this table one would have to use a hydrometer in the API gravity scale. DO NOT use a hydrometer for reading battery electrolites or beer. Those hydrometers are calulated for measuring water based fluids.

On the API gravity scale, the higher the API number of the fuel translates into a lower BTU content. It's an inverse scale.

I hope this clears up some of the confusion.

 

[TurbinePower]

The BTU content of methane is very stable at 1000 BTUs per 1 standard cubic foot (scf). A standard cubic foot is defined at 15.6C/60F at sealevel, or 14.7 PSI, 1 Atm, 101.3kpa, etc. The common unit for methane usage is the therm. A therm is 100,000BTUs of energy content. So 1000 cubic feet of methane equals 1 therm.

Aren't you off by a factor of ten on the cubic feet to a therm? If each SCF is 1000, and you've 100,000 BTU to a therm... then you'd only have 100 SCF per therm, not a thousand.

 

[DPM]

This isn't actually an alternative fuel for TDIs is it?

 

[BKmetz]

You're right, 1000 x 1000 = 1 million. I know this too because in the heavy fuel oil business a common abbreviation is MM/BTUs hour, which uses Roman numerals for 1 million.

I edited my post to make the correction.

Aren't you off by a factor of ten on the cubic feet to a therm? If each SCF is 1000, and you've 100,000 BTU to a therm... then you'd only have 100 SCF per therm, not a thousand.

 

[cessna]

Decatherm is also another way of expressing 1 million btu's. My latest natural gas bill shows the price for last month at 2 days for $.43/therm and 27 days at $.52/therm. I think the base rate(transportation through the pipeline) is $.13/therm that is added to the previous figures. We have a lot of dairies and hog confinements around here that should have methane digesters installed.

 

[GoFaster]

This isn't actually an alternative fuel for TDIs is it?

I have a funny feeling that either the original poster has not figured that out yet, or has proposed converting the engine to spark ignition, or is proposing to use it as a power-adder like propane injection is used. I get the feeling that the original poster has never tried fitting a CNG fuel system to a diesel engine. Or, I could be wrong.

 

[UFO]

I have a funny feeling that either the original poster has not figured that out yet, or has proposed converting the engine to spark ignition, or is proposing to use it as a power-adder like propane injection is used. I get the feeling that the original poster has never tried fitting a CNG fuel system to a diesel engine. Or, I could be wrong.

A Volkswagen is a Volkswagen, right?

 

[kcfoxie]

Interesting.

1) Propane injection / Methane/Natural Gas injection has been done on many diesel trucks for some time, and some TDIs. Not that uncommon.

2) Honda Sells a natural gas vehicle, crash tested, DOT approved since 2004 (2005? can't remember): http://automobiles.honda.com/civic-gx/

3) Natural Gas prices fluxuate around the country so saying 60-cents a gallon is really only applicable to where YOU live and not a standard I'd be pushing for marketing purposes.

Honda cites an 8 gallon tank capacity and a 250 mile range on said capacity, using the same VTEC 1.8L that is found in the gasoline model. Their numbers show an avg of 31mpg and 28/36 city/highway, which is slightly better than the gasoline model with slightly reduced power. The tailpipe emissions are quite lower than gas or diesel.

However, Honda states that owning this car PLUS the $6000 some odd dollar Phill at home CNG filling station (it takes 2 hours or so to fill their vehicle) is about like operarting the gas model if gasoline was 1.50 a gallon.

Take that how you will.

I don't believe you're going to get this to work in a diesel as the sole fuel without some very creative engineering. As a power boosting or supplemental fuel sure.

You DO realize you're posting on a forum where most people see 45+ MPG on a consistant basis, where the best of VW's gas lineup stops at 34MPG... right? There is little in way of convincing us, many of whom have been on the biodiesel bandwagon for many years which is just as clean as CNG in respect of being a renewable resource made from recycling old feedstocks and wastes, that this is not just a waste of money unless you can show a 20% or better improvement over the stock fuel economy, and we're going to want to know who your software vendor is because you're not making this work in our engines w/out software reprogramming.

Lastly, you've failed to tell us (and I've not read your site) if this is DOT approved / safe and what the insurance companies say about it. This was a major talking point at the NC Green booth which I worked at the Fair this year, and many people liked the Factory CNG vehicles but said conversion was not really worth it given the expense of insuring and certifying the car with the DOT.

That all said, a factory built CNG car like the Civic GX is actually a fabulous commuter vehicle in many ways, and I wish VW would bring back the 2.0L and use it as a CNG prototype in a Beetle or Jetta. But I'm quite leery of the conversions.

Oh and really, you're not winning any of us over with the patriot / home made fuel -- we started doing that in the 90s, and using raw veggie oil in the 80s. We also bicker about the reliability, as many of us expect no less than 300,000 miles out of our vehicles (do you get that out of a gasser? The best I've gotten was 215,000 and blew a hole in the engine block of the 2.0L, 98 AEG Beetle).

 

[BKmetz]

Or, I could be wrong.

Or you are really quite right and hit all those points dead on....

I could add a lot more to your list.

 

[kcfoxie]

I personally want to see a TDI running this kit, and see a dyno sheet, UOA after a 10k cycle, and fuel economy logs before I buy into it.

 

[CNGVW]

Hello if you looked at my site you would see I have all ready done the 1999 VW Bettle
2L Converted to BI-Fuel CNG and have 2years of testing under my belt.
This is why I have mover up to the Turbo engines. I am not here to fight I just stopped listening to all the misinformation out there.
For the Honda to make the 250 miles to the tank you would have to crawl.
The pump that you speak of takes 1 hour to the GAL of CNG to fill…
For the biodiesel bandwagon I have never said any thing badly about it.

For the DOT thing it is the EPA that run the show here and here are the people to call

Reineman.Martin@epamail.epa.gov
734-214-4430
US EPA Office of Transportation and Air Quality Compliance and Innovation Strategies Division
Mat Carlile
Department of Environmental Quality-Air Division
Environmental Scientist
801-536-4136
mcarlile@utah.gov
Dianne R. Nielson, Ph.D.
Energy Advisor
State of Utah
DNIELSON@utah.gov
Cheralyn Anderson
Dianne Nielsons assistant,
cheralyn.anderson@utah.govor
801-538-8652
Who’s Afraid of the Big Bad (EPA) Wolf
After several meetings with the EPA along with my own research and numerous discussions with others in the CNG (Compressed Natural Gas) Conversion Industry, I have come to the conclusion that the EPA is not the Big Bad Wolf some people have made them out to be.
Opinions are as the saying goes “a dime a dozen”. Like most things and especially a new technology or a new way of doing things there are always many opinions. I have learned to take all opinions with a “grain of salt”; all opinions except my own, of course; it holds a little more weight with me.
Over the years I have personally owned over 50 vehicles, from a 21 Window VW Micro Bus to a Turbo Charged 5-cylinder Audi 5000. In all of that time I have never worried about whether or not any of these vehicles were “EPA Certified”. I have had to do emission tests and some safety inspections but no EPA anything. In my more than 30 years of automotive repair I have worked on thousands of vehicles in 3 different States doing anything from tune-ups to complete vehicle restorations. It wasn’t until last year (2008) that I had even heard of CNG and CNG conversions. As I researched this topic I became concerned about what people were telling me about the EPA hoops a person must jump through in order to have a supposed “legal” CNG Conversion and what EPA Certification really is.
As I searched forums and the internet I started hearing blanket statements like “All CNG Conversions must be EPA Approved” or “non-EPA CNG Conversions were not legal to drive on the streets”, and “the EPA will fine you $1000’s of dollars if you are caught converting or owning a ‘NON-EPA’ CNG Vehicle”. Over the past few years I know that this type of rhetoric has kept hundreds if not thousand’s of individuals from converting their vehicles to CNG because of fear of the EPA. An incongruity began to form in my mind. Why was it that CNG vehicles and CNG Conversions had come under so much more scrutiny than any other group of vehicles? I began to question the sources of these EPA Certification statements. Where were these statements coming from? Was it anyone who actually had any authority over me or were they just self appointed bullies and safety monitors? As I dug deeper a pattern arose, those raising the “EPA only” banner usually sold or developed “EPA Certified” CNG Vehicles or Systems. The EPA when asked about the EPA Certification of CNG Vehicles was unusually silent or ambiguous on the subject. Since I have a background in the legal field I noticed that there was something about the broad blanket statements about “EPA Certification” that didn’t seem right.
Over the next year I researched the EPA Code and website searching for the one rule stating that “All CNG Conversions must be EPA Certified”. It was nowhere to be found. It just didn’t exist.
As these false statements about the requirement for “EPA Certification” began to spread people began looking for EPA Approved Installation Stations and EPA Approved Technicians. There were none to be found. They just don’t exist. As I learned later, after numerous meetings with the EPA, the main purpose EPA Vehicle testing division is to Certify OEM (Original Equipment Manufacture) vehicles to meet Emission Standards for “the useful life (100,000 miles or 10 years)” of the vehicle.
In the late 90’s due to inefficient CNG conversion systems the EPA was tasked with “certifying” CNG Conversions. Since their testing procedures were for NEW OEM Vehicles, they used a similar standard for the CNG Conversions. The EPA can’t and never will certify anything other than new vehicles due to deterioration factors and the vehicles useful life.
What exactly is EPA Certification? It is a series of tests that show that a vehicle will continue to run clean for the specified time. It is not a guarantee or warrantee, it is just certificate given after a series of tests have been completed. While we are talking about EPA Certified CNG Conversions lets take note that any EPA certification expires beyond a specified time (the useful life of the vehicle). Just like any other vehicle, all CNG Vehicles need to be re-tuned, maintained and re-tested from time to time.
Aftermarket CNG System manufacturers go through stringent testing procedures since they build their systems for various vehicles. These companies use inputs from the vehicle’s own sensors and electronic control units. Most of the new generation of CNG kits have independent MAP (manifold absolute pressure) sensors, coolant temp sensors, natural gas pressure and temperature sensors. I would venture to say that these new generation systems can outperform most “certified” CNG Systems on the road today. In fact, if a person was to compare the components of a “Certified” and a “Non-certified” conversion system it would be hard to tell the difference.
To summarize:
1. No CNG Conversion is required to have EPA Approval. Individual companies can choose to have their CNG System certified by the EPA.
2. The EPA can only certify new vehicles (CNG or other) for the useful life of that vehicle.
3. All EPA Certifications expire after the useful life of that vehicle.
So are you still afraid of the Big Bad EPA Wolf? I’m not, and hopefully you aren’t either. In a recent meeting with Marty R. from the EPA in the question and answer portion I asked why the EPA Certification sticker was not removed after the vehicles “useful life”. Marty responded that indeed no one recertified their vehicles. When I asked how many “Illegal CNG Conversions” had the EPA’s enforcement division prosecuted and fined the answer was “None, not a one”.
http://www.younkincng.com/

 

[kcfoxie]

ok, so make this work in a diesel and report back. i'll buy the epa statements, but I still don't think you can make this work the same as it does for a gasoline engine.

 

[DPM]

Yup. Show us a video of an electronically-controlled TDI running on NOTHING BUT CNG then it's a worthy post for this subforum.

 

[kcfoxie]

I'd also like to say it's less the "Big Bad EPA Wolf" I worry about and moreso the Big Bad NC State Highway Patrol who will dip tanks and confiscate vehichles that do not meet our state's guidelines for crashworthiness or safety. It's not unusual for a them to setup outside, say, one of the MANY NASCAR events and check vehicles for compliance.

Prior to the state making laws specifically regarding Waste Veggie Oil used as Fuel and home-brewed Biodiesel they had all the hardware needed to dip your tank (any diesel engine was subjective) and verify you're using an on-road, taxed fuel.

Since there aren't any road taxes paid on CNG I'm not sure how the state handles it, despite requiring CNG Hondas and Ford Trucks for state operations and the local power companies (hence why I know so much about the Honda, they are for sale here cheap since the dealers don't know what to do with the off-lease units).

So, I'm sorry if me not wanting to go to jail is somehow offensive or attacking of your business model. SOME of us know that good ideas like these can lead to frustration, jail time, and potentially being dropped from insurance.

I'm also not so sure that Honda is going to cite that you can 'only go 250' miles at 45mph since the vehicle is designed for on-road use, not campus like like an Neighborhood Electric. Even if that's so, that means the VWs should only go similar distances since they're using small sized tanks. To me your being very inconsistent.

Did we mention that many on this forum are Engineers, in the Aerospace business, or generally work in Defense/Research and are highly educated and question every single aspect of something before making a decision? You've got a very tough audience. We are not the same as the 18-26 year old VWVortex douches who buy 1.8T's and can't be won over with "60 cent a gallon" rhetoric. Again, most of the vehicles here exceed the best of VW or The Asian's cars by 10 to 15MPG. We've already done extensive calculations on the cost of operating the car, adding in something like this becomes a new weak point for repair, much like most of the WVO/Veggie oil systems. Sounds great in theory, in the real world not so much.

How often do you change the oil using this fuel?
What are the potentials for failure?
What's the expense of repair to the failure-prone parts?
Will this last 18 years / 310,000 miles ?

These are the questions on my mind, and if you're wondering why I want it to last some crazy amount of miles it's because my not-yet-3 year old car has 99,558 miles and I bought it with 218 on the clock in 2007 new. I expect no less than 310,000 out of it before it's replaced, with an expected 7 year service interval. How does your product benefit me when I've already worked out maintenance schedule and bought parts for the next 200,000 miles of operation?

I'm genuinely curious but also a skeptic. The "It worked in one VW so it'll work in any VW" mentality that you display simple scares me and does not cut the mustard.

Also, register as a vendor before you get banned. They've asked you twice now.

 

[GoFaster]

CNGVW, you can spare me the EPA political situation, and answer me these two very simple technical questions.

1. How do you propose to meter the natural gas into the engine in proportion to requested engine load from the accelerator pedal (given that the TDI engine has no throttle and the engine "load" signals are only available electronically)

2. How do you propose to ignite methane in the cylinder in the absence of diesel fuel. (It won't ignite by compression alone - at least, not with the stock compression ratio)

Answer those two questions ONLY, and SKIP any discussion about what you've done to spark-ignition engines. Can you handle that?

 

[CNGVW]

Good to see your back
For the running on 100% CNG it will take some work but a blend
Say 20% Biodiesel and 80% CNG will work and under turbo load and with out parts failing.
For oil change I can push them to 20,000 with Synthetic with CNG where there is nothing to break down and contaminate the oil.

For safety I am certified in all CNG aspects and the installs follow the FPAS 52
Guide lines.

As I was at the http://www.altwheels.org/index.html fleet show I made the news a lot there The EPA was so kind to spend some time with me and go over my cars and set up they had some very kind works on my set up and the cars.

If this how your people (Did we mention that many on this forum are Engineers, in the Aerospace business, or generally work in Defense/Research and are highly educated and question every single aspect of something before making a decision?)

Treat new ideas and for help and wth testing I did come to the wrong forum.

 

[DPM]

So it's NOT an "alternative diesel" fuel then?

 

[ToledoTDi]

A quick google yielded this from http://www.omnitekcorp.com/engconvert.htm

[FONT=Verdana, Arial, Helvetica]Diesel Engine Conversions
May need to improve cooling system efficiency
May need engine oil cooler
May need new valve seats, guides and seals
May need new pistons and rings
Engine compression must be lowered
May need a new camshaft
Ignition system must be installed
Cylinder head modifications are needed to install spark plugs
Custom cam or crankshaft position sensors must be made[/FONT]

A new engine would be the short answer

 

[BKmetz]

From Omnitek's website;

[FONT=Verdana, Arial, Helvetica]2. Engines with a turbocharger - must use electronic fuel injection (ECM).[/FONT]

[FONT=Verdana, Arial, Helvetica]


Plus imagine what would happen if the CNG tuned ECM failed, or there was an electrical/mechanical failure to shut off the CNG during a catalyst regen cycle on the newer diesels!!



[/FONT]

 

[brucebanes]

He is going to post that 'You are not team players' and something similar to 'I guess you want to Arabs to blow us up'. He comes here pimps his stuff and then feels insulted when technical questions are asked. I looked forward to observing his future bankruptcy. They were better solutions that failed in the past like the EV1 because technical limitations were not addressed (Batteries are expensive and wear out) and their failure was blamed on politics or collusion. You are doing the same thing and setting yourself up for failure.

 

[BKmetz]

We have seen this a million times before, biodiesel, oils, WVO, HHO, the list can go on & on. Some ideas are total crap, some are total scams, some just don't justify the expense. Some actually survive!

Someone thinks they have the next big idea. The idea becomes an ideology and they become evangelists for the idea. The ideology and evangelism trumps technical knowledge. They discover TDIClub and post the idea on its forums. TDIClub suffers fools poorly and the idea is vetted out on the forums. The poster of the idea is sure of himself and doesn't understand the vetting process to see if the idea has technical merit.

The vetting process can be civilized, indifferent, or quite brutal, depends on the poster's knowledge and how they present themselves. The OP doesn't understand that this is simply the normal vetting process that happens every time someone posts their great idea here. All the OP knows is that he is not getting the response and support he thought he would get. Also, the OP doesn't understand that this thread is very, very civilized compared to how most of these threads go.

 

[GoFaster]

It's also worth noting that the conversion site mentioned above requires that the engine be converted to spark ignition (with throttled air supply). It also requires the pistons to be changed. This process will also render the engine incapable of being operated on diesel fuel. I know of this type of technology.

Dual fuel engines that retain the diesel injection system and use that as "pilot injection" - to light off the premixed methane/air charge - have been known for decades. Those don't require throttling. Doing this on the VW TDI application would require the electronics to be reprogrammed to properly meter the natural gas into the engine.

 

[andreigbs]

So basically what you're saying is that, to make ANY of this CNG stuff work, it would be much more costly to adapt your current TDI that's running just fine on D2 or BioD.

Why would anyone want to spend money needlessly on an unproven system?

Why would anyone want to start replacing pistons, air supply method and ECUs on a perfectly good running TDI, except as a lab experiment to see the results and say "yeah, it wasn't worth it"?

Sorry, OP, you've got a tough crowd here. You've still not mentioned if you've actually converted a TDI to run on the stuff. As others have pointed out, you seem to think all VWs are basically the same.

 

[heuiinj]

If this how your people (Did we mention that many on this forum are Engineers, in the Aerospace business, or generally work in Defense/Research and are highly educated and question every single aspect of something before making a decision?)
Treat new ideas and for help and wth testing I did come to the wrong forum.

If I was going to throw out a trial balloon on a new fueling concept I'd definitely end up here. The general knowledge base of most members here is second to none.

I started dealing with Liquid Propane fueled vehicles in the late 1950's in auto shop at high school. We ran "dual fuel" which consisted of a propane vapor mixer on top of a normal gasoline carburetor. Lock-off solenoid valves on each fuel supply to turn one off and the other on. Usually we would switch from LPG to gasoline when going downhill to allow time for the carburetor to fill. But the concept is much like blending CNG or LPG with diesel in that 2 completely separate fuel systems are required onboard.

Not anywhere on your site I see mention of the tank required for CNG. As CNG requires 3000+ PSI heavy wall tank to keep it in the liquid state necessary to carry enough energy or BTU's to be practical for a small enough tank in a VW.

I'd be a bit skeptical as to the practical advantage you would gain adding a CNG system. The average TDI can go up to 15 miles on a quart of ULSD weighing less than 2 pounds. CNG would be a hard sell for me..

 

[T'sTDI]

It's also worth noting that the conversion site mentioned above requires that the engine be converted to spark ignition (with throttled air supply). It also requires the pistons to be changed. This process will also render the engine incapable of being operated on diesel fuel. I know of this type of technology.

Dual fuel engines that retain the diesel injection system and use that as "pilot injection" - to light off the premixed methane/air charge - have been known for decades. Those don't require throttling. Doing this on the VW TDI application would require the electronics to be reprogrammed to properly meter the natural gas into the engine.

That's a good point and a point that renders a CNG conversion on a diesel engine pretty much useless. You start with a diesel engine but yet you have to adopt traits of a spark ignition gasoline engine.

So to the OP, whats the point in converting a diesel engine when it is much easier to do so starting off with a gas engine?

 

[AndyBees]

Coal fired electrical plants ...... on decline!

Which is a good thing. I wish we had more nuke plants. Coal plants are on the decline, but they're still out there.

Can you provide a link(s) to info about coal fired electric generation plants being closed or cutting production?

The EIA (Energy Information Administration) (official energy information statistics for the US Government) shows that coal use, as well as other sources has stayed basically flat for the last several years. The variations are so small that no trend can be discerned, except for wind power (tons of our tax dollars to support).

Coal has led production with about 5 billion Kilowatthours per day with Nuclear at about 2.2 billion Kilwatthours per day. And, as an example, wind has increased over the past four years from 0.049 to 0.169 billion Kilwatthours per day. That is a significant increase over 4 or 5 years, but in some places the construction has come to a halt due to environmental concerns (go figure).

Shut down the coal fields, and the USA comes to a screeching halt!

 

[GoFaster]

Can't speak for USA, but locally (Toronto area), the Lakeview coal-fired generating station near Toronto has been demolished and Nanticoke is planned for shutdown. Meanwhile, they've just built one big gas-fired generating station here in Brampton, and there's another one under construction in Halton Hills, and there are a LOT of windmills in operation near Shelburne and they are constantly building more. There is talk of expanding our nuclear plants, but that is far into the future due to the lead-time involved. The Ontario government has been on a mission to shut down all coal-fired power generation, although they've had to delay those plans somewhat due to impracticality of building replacement power in a fast enough timeframe.