CNG, is it the Answer for the Fuel Crisis?
Or All American Super Flex Fuel
 
 H. Kent Sundling

Update: we dyno our CNG mule.

Six inches of snow on the ground, cold January day in Colorado. We took our test mule to Engle Automotive in Loveland for the dynameter test.  In Front Range counties, Colorado requires diesels to be tested for emissions. Our test truck with the CNG conversion passed with and without gas. Similar results, CNG helped the middle RPM range lower emissions.

Power proved what my butt dyno was saying. Torque improved 285 ft. lbs of torque (correction 245 torque) with CNG and horsepower up 85. Just returned from California, bought CNG in Utah for $.88 Gasoline Gallon Equivalent. When I know it's the next CNG fill up is way down the road, I save the CNG for mountains and long grades. Video....


Forget veggie oil, bio-diesel, power programmers and hydrogen water separators. And hear the gospel of CNG/diesel. The beauty of this system is if I can't find a Compressed Natural Gas fill up station, I just run on diesel. We've now had time to run several tanks through our test truck in a loop using both CNG and diesel together at 2 to 1 (2 CNG gallons to 1 diesel gallons) without a trailer and about 1 to 1 with a trailer. We reduced our fuel cost per mile 23% to 27% with Colorado prices. Almost double that with Utah prices, (details below.) Which is like buying diesel at $3 instead of $4 or increasing MPG by 25%.  CNG prices range from $.50 to $1.20 cheaper than diesel. And did I mention more power? It's not about waiting for a hybrid truck or hydrogen fuel cell to save us, but something we have in abundance in the USA that we can use now. You see the T. Boone Pickens ads on TV every day. There's something to his plan with natural gas. Propane and CNG have been used to boost diesel engine power, but I'm talking about replacing most of the diesel with CNG.

P
art of the story, is how hard it is to get CNG fuel. Hard to find in some states and complicated to buy in other states. Many fueling stations use a special card only, that you have to apply for. Mark Deluca installed my unit in Ohio, he had to fill me up, as a special card was required, the same for a station in Indiana.

I had to go to Ann Arbor near Detroit to get my next fill. And since CNG stations are farther apart than my two 10 gallon tanks will run, I can't get a tank to tank read on what my cost per mile is. Which is the only accurate way to judge what I'm saving by using CNG. A week ago I faxed in my application to Clean Energy, which controls all the CNG filling stations in Colorado. I downloaded the app from www.CleanEnergy.com and faxed in my 4 page application plus copy of credit card and drivers license. They require a $100 deposit and bill your credit card a day after you use their special cards to buy CNG. Clean Energy HQ is in California where they operate dozens of stations that use credit cards like a gas station. This should spread to other stations around the country as CNG becomes more popular. Clean Energy bought Phill Home Fueling Stations (www.myphill.com) which install on your homes gas line for CNG filling with low pressure (one gallon per hour). Clean Energy is also in a joint venture with GM for opening Hydrogen cell fueling stations. T. Boone Pickens owns part of Clean Energy.

 
 

In the Clean Energy station locator brochure that came with my fuel cards, is a listing for fill station on Ft. Carson Army base near Colo. Springs Colo. Yes I filled there, after the gate private contractors searched my truck and warned me I could be arrested on the Army base for wondering around. Not sure why, the gate guards didn't know there was a public CNG fill station there or what CNG was. So after a phone call, they did tell me where it might be. Filled my tanks and got out of there. Could have used a warning in the Clean Energy locator brochure about military bases. So far I've bought fuel in Colorado, Ohio, Michigan, Kansas and Oklahoma. But just one military base. Most stations are located near government centers, airports or natural gas service centers.

As a kid on the farm, we had a propane Minneapolis Moline farm tractor, filling propane was a pain. But CNG is a snap with just a coupler, similar to a air compressor coupling with a locking lever. Gasoline Gallon Equivalent is how CNG is sold at the pump, so you don't have to bring your calculator to convert BTU's into cubic feet and then into gallons. You're buying natural gas as equal to a gallon of gasoline.

So far using CNG in my 2006 Ford F250 diesel test truck added 180 miles to my overall range. 280 miles on CNG/diesel with a trailer using two 10 gallon tanks.
Paid $2.19  for CNG in Ohio in September, $1.94 in Michigan, $1.26 in Oklahoma and finally dropped in Colorado to $2.09.  Twenty CNG stations in my state, Colorado, 62 in Utah, 51 in Oklahoma, 92 in New York, 40 in Arizona and 183 stations in California. 778 stations in the country. Utah ($.80 this week) and Oklahoma ($1.14) have the cheapest fuel. For current prices and locations, http://www.cngprices.com/

 With diesel and gas prices doubling in one year, no one was prepared for this. We knew higher prices were coming and oil is running out, but not all at once. We all feel the pain, from fuel prices. But the good side and there always is a good side if you look hard, the dramatic fuel price increase has put the whole country on alert speeding up development and brain storming for a solution.

For the businesses that survived the fuel crisis, bank crisis and bail out crisis, it's time to sort through the new ideas for the real improvements in mpg for commercial trucks and pickup trucks. I've tried engine programmers, bigger exhaust, bigger air intake, roof wings, lower air dams, tonneau covers etc. and never got a large improvement of more than 10%.

Reading Diesel Power Magazine with a diesel truck mod shootout, one of the trucks had  CNG added to a Duramax getting 38 mpg. Sounded interesting but didn't sink in until my nephew Greg called, wondering if I had more info on CNG. Researched the source and found Marc Deluca in Ohio up to his elbow's in installing CNG on diesels. http://www.delucafuelproducts.com/ Called some engineers at Ford to see what would happen if I added CNG to our test truck, a 2006 F250 with the 6.0L Power Stroke diesel with new head gaskets, new EG cooler and 65,000 miles. The main concern was boost and internal cylinder pressures. The boost was actually reduced with CNG. We may try a boost regulator before we go to larger loads than the 10,000 lb trailer we're using now. My concern was lubricity since I would be using less diesel, I was told by an engineer that lubricity wasn't a problem as only diesel was going through the injectors and pump where lubrication was a concern. CNG was entering the engine through the air intake, mixing CNG with air in the turbo.

Mark Deluca explained that CNG makes the engine more efficient, diesel explodes in the center bowl of the piston and leaves some oxygen and diesel unburned in the outside ring of the piston. CNG helps use the fuel and oxygen in the outside ring, giving you more power. Diesel engines compress hot air and CNG for a more complete burn of fuel and air in the compression stroke. Since adding the CNG venturi tube in the air snorkel after the air filter, the low pressure fumigation system, CNG fuel is sucked into the turbo and mixes air with CNG as it travels through the turbo and intercooler on it's way to the engine. No CNG is used at idle and it takes about 1500 rpm to open the spring valve on the regulator for the gas to flow. Drawing CNG into intake manifold has advantages over bio-diesel or waste oil which goes thru pumps and injectors causing some problems on seals and o-rings or gelling from cooking oil waste/fuel.

You can also convert your gas engine to CNG, a diesel conversion though doesn't have problems with predetonation or need knock sensors like a gas conversion. Diesel engines is built for heavy duty use, exploding diesel with heat and combustion not spark. This all makes diesel engines the ideal CNG conversion candidate.

Talked to farmers in Ohio who built a portable unit with regulators and argon gas tanks for CNG that lifts out of their Dodge 2500 with Cummins diesel and onto a combine for corn harvest. They have natural gas wells and get some free CNG. Even with an expensive step-up pump, they said they saved a couple hundred dollars a day using CNG in farm equipment.

Major companies are working on CNG projects, John Deere has CNG gas engines in trucks and buses, Cummins has a CNG engine and in 2001 Cummins had a 15 L Cummins/Westport LNG/diesel (Liquefied Natural Gas) that they tested which burned mostly LNG with a dual injector with diesel. Mahindra Tractors is launching new models, using CNG and LPG. They estimate that the new models will be at least 30 per cent more fuel-efficient than diesel-run tractors. UPS bought 167 new CNG vehicles in April this year. UPS seems to be on the cutting edge with new technology using diesel hybrids and hydraulic propulsion.


CNG, which is 80 to 95 percent methane gas, "Natural" gas is the key word here, same methane you smell driving by a feedlot or dairy. Waste Management harvests methane natural gas from it's landfills to run their garbage trucks. Methane gas is renewable. Natural gas has a simple chemical make-up: one molecule of carbon and four molecules of hydrogen (CH4). 

That's what makes it burn so cleanly. Oil and coal are more chemically complex. They contain higher proportions of carbon, sulphur and nitrogen. Maybe CNG is a better solution to cleaning up diesel emissions for the next emissions law hurdle in 2010. Might be an alternative to urea which the 2010 diesel trucks will use to produce clean diesel. CNG is much cleaner-burning than gasoline. According to the Environmental Protection Agency, CNG can reduce carbon-monoxide emissions by 90 to 97 percent and nitrogen-oxide emissions by 35 to 60 percent when compared with gasoline. CNG can also potentially reduce non-methane hydrocarbon emissions by 50 to 75 percent, while producing fewer carcinogenic pollutants and little or no particulate matter. When the 1998 Civic GX was introduced, the EPA cited it as having the cleanest internal combustion engine ever tested. CNG is a safe fuel as it's lighter than air and dissipates when released into the atmosphere while propane is heavier than air, congregates at ground level. CNG tanks are certified and have stamped on them a date from 10 to 20 years to be recertified.

Compressed Natural Gas, comes back in fashion when fuel prices soar. It's an old solution not promoted as well as ethanol and hybrids until now with T. Boone Pickens on TV everyday. During the last two fuel crisis's, there were more CNG fuel stations and dual fuel conversion companies, cheap gas came back and many CNG guys went bust. Here we are again with fuel prices dropping, maybe another cycle. But then there is the national security issue of buying oil from the bad guys and crude oil is still running out. The warning was pretty clear this time and panicked our nation.

The infrastructure of CNG filling stations will need to increase to allow expanded use and competition. Right now your choice of new vehicles is limited to one: The Honda Civic GX. Some California Honda dealers where offering the Phill Home Fueling Stations as an option with natural gas Civics. Toyota will introduce a natural gas Camry at the Los Angles Auto Show in November. GM and Ford during the last CNG surge, made several models of natural gas cars and trucks. One out of five buses use Natural Gas today. CNG has the ability to improve Cost Per Mile 23 to 48% from my test. Yes big numbers, some improvement in (MPG) Miles Per Gallon, but real costs for us on the road, the same way the IRS gives you a a business deduction, as cents per mile.

Pictures at left are the venturi tube in the intake elbow before the turbo, the turbo draws the CNG into the engine. Around $1800 for a CNG diesel/conversion system, another $3800 for a new 30 gallon carbon fiber tank and it isn't cheap. My tanks were used, similar to what you find on EBay. But if you put miles on your truck like I do (30k/year), it can still pay for itself in a year depending on which state you get most of the CNG from. Those of use towing trailers across the country can benefit the most, because we spend the most on fuel.

We haven't dyno'd the test truck yet. I'm hearing from folks using CNG and propane boost that they get from 60 to 100 hp increase. It's easy to see the power boost, flipping the switch with the cruise control on. Nice on the Interstate on-ramp with a trailer, the extra power helps.  I'm sure the 130 octane from CNG, and cooler condensed air caused by the pressure drop from 3600 psi in the tank to 200 psi in the regulator, all contribute. We ran hoses from the trucks recirculation reservoir to the regulators to keep them from freezing from the pressure drop.

Having the correct spring setting in the regulator, controls how much CNG goes in the engine and at what RPM the engine sucks in the natural gas mixture. The unit has adjustments for pressure and volume. You use less throttle for the same RPM, because of the reduced diesel consumption. Fine tuning the volume control determines how much flutter you have when you let off the throttle or drop below the RPM that gas is drawn in. That was around 1600 rpm on my test truck. Torque peak on a 6.0L Power Stroke is 1800 rpm, so I gained some bottom end power.

In Detroit I drove Louie Fecteau's 2001 GMC Sierra 2500HD Duramax/Alison with the Deluca CNG dual fuel conversion. He had similar fuel economy improvements and said turbo lag was eliminated. Louie installed a new Lincoln Composites CNG 21 GGE Tank, carbon fiber composite 30 gallon tank, 200 lbs verses my two tanks weighing 400 lb.

Louie's truck stutters at 1500 rpm when CNG shuts off. Louie changed to a lighter spring in the regulator for his first generation Duramax with less vacuum for better CNG fumigation draw. Louie put his regulators in front of rear wheel well on the drivers side. Marc Deluca installed his regulators in the engine compartment of his GM Duramax. My unit is installed in the bed next to the tanks along with pressure gauge and fill nipple.

Found my trucks sweet spot for fuel savings and drivability. Changed volume setting 5 times,  highest setting had 3 CNG to 1 diesel. But it was surging at highway speeds as anytime the cruise control adjusted itself on hill or wind, the reaction was a surge or pulse at set speed. Adjusted volume down, took the surge out, drivability is now same with or without gas. So I can have it on all the time. The amount of natural gas that will fill your tank depends if the fuel dispenser is 3600 psi or 3000 psi and if it's a hot day or a cold night. 30 gallon tank equals 21 gallons CNG in general, my two 10 gallon tanks equal 13 gallons at 3000 psi 17 gallon at 3600 psi. I should be able to load 18 gallons on a hot day into my 20 gallon tank.

The Results

Towing a trailer had a 23% reduction ($.10) in cost per mile, from $.43 to .33. MPG improved 12% from 9.08 to 10.3 miles per gallon combined both fuels. 22.2 mpg CNG, 19.18 mpg diesel. This fueling at less than one to one, .75 CNG to 1 part diesel.

Empty truck had a
27% reduction in cost per mile, from $.26 to .19. MPG improved 8% from 15.36 to 16.48 combined fuels. 26.92 mpg CNG, 42.53 mpg diesel at 2 CNG to 1 part diesel.

This is with diesel at $3.94 and CNG at $2.74 in Colorado,  September 08. CNG is sold as Gasoline Gallon Equivalent equal to gas in BTU units at 114,100 blended by Xcel Energy to achieve said BTU.

Using my gallons used for CNG and diesel, I converted to Utah prices for CNG and diesel. Average diesel price in Utah was $3.59 the same week I paid $3.94 in Colorado, CNG in Utah averaged $.88 with Colorado as one of the highest states for CNG prices at $2.74

Towing a trailer on Utah fuel could have a 45% reduction in cost per mile from $.40 to $.22. Empty truck could have a 48% reduction in cost per mile from $.23 to $.12. Can you imagine driving for $.12 a mile? It would be equivalent to driving a car that got 30 mpg on $3.50 gas. Tempted to move to Utah or Oklahoma. From what I've found, CNG is from $.50 to $1.20 a gallon cheaper than diesel.

Turbo boost dropped in half using CNG. I think with a boost regulator, increasing boost would allow using more CNG or an injection system. Other diesel engines may have the ability to use CNG more efficiently, that will be another review, maybe a Cummins or Cat. This is the largest increase of fuel savings we experienced on our test truck 2006 Ford F250 Power Stroke diesel.

One of the benefits of natural gas as fuel, is they burn cleaner, releasing smaller amounts of by-products of combustion (carbon particulates and acids) into the motor oil. Because the oil stays cleaner longer, it’s possible to expect longer intervals between oil changes.  

At the CNG pump in Colorado is a $.06 a gallon Federal Excise Tax.  This may be deductable with the IRS. There are incentives, grants and rebates associated with alternative fuels like CNG. In an effort to reduce America's dependence on foreign oil, reduce emissions and greenhouse gases, the US federal and state governments have incentives to encourage the purchase and use of natural gas vehicles (NGVs). Conversions especially for diesels may or may not meet EPA requirements, most are sold for off-road use, be sure to do your on research. Tax Incentives

Use to see refineries burning off natural gas to get it out of the way. Now natural gas will play a major role in American trucking. In California, Clean Truck Programs at the Port of Los Angeles and Long Beach, which starts (Oct. 08), bans trucks 1988 and older from entering the ports. January 1st 2010, trucks model year 1989-1993 will be banned from port terminals along with unretrofitted 1994-2003 trucks. On January 1, 2012, all trucks must meet 2007 federal clean truck emission standards. Using natural gas in port trucks can reduce green house emissions by 20 percent and nitrogen oxide emissions by 75 percent. Sterling is producing for the port a truck powered by a Cummins Westport spark-ignited natural gas engines. Well maybe not, Daimler just announced the demise of Sterling in March of 2009. So more than likely Sterling's big brother, Freightliner will have natural gas trucks for the ports. The extra cost of the NG engines is being covered by grants from California.

Total Transportation Services, Inc., a  transportation company in Rancho Dominguez, CA, trucks to the Ports of Los Angeles and Long Beach. TTSI is operating eight Kenworth T800 liquefied natural gas (LNG) trucks, the first alternative-fuel vehicles to operate in full-time drayage service at the Ports of Los Angeles and Long Beach under the major Clean Trucks Program. Liquefied Natural Gas, LNG is better quality, takes less space for fuel tanks compared to CNG. But takes special insulated tanks for 260 degrees below zero to keep it liquid.

TTS's eight Kenworth T800s are equipped with the LNG fuel system developed by Westport Innovations Inc. of Vancouver, B.C., and installed on the Cummins ISX 15L engine. The Kenworth T800  LNG Cummins ISX 15L engine has 450-hp and delivers 1,650 lb.-ft. of torque. The Kenworth trucks have Westport’s High Pressure Direct Injection (HPDI) technology and use five percent diesel and 95 percent natural gas.

Earlier this decade, Cummins Westport Inc., a joint venture of Cummins Inc. and Westport Innovations Inc., in 2001 completed  the first multiple-unit delivery of heavy-duty trucks using the low-emissions ISX-G heavy-duty natural gas engine. The multiple-unit delivery involved 14 Peterbilt heavy-duty trucks to Sanitary Fill Company in San Francisco, a subsidiary of Norcal Waste Systems Inc. 

Read the Norcal Waste Systems natural gas truck test at http://afdc.energy.gov/afdc/pdfs/35427.pdf  The liquefied natural gas was hauled from Wyoming to Sacramento CA in 2001, because of the high cost of transporting LNG to California, diesel fuel was cheaper than LNG. The test did show the diesel/natural gas engines performed better than the spark-ignition engines in prior test.

Back to pickup truck natural gas conversions, there are four types of tanks, all-metal or aluminum, hoop-wrapped steel or aluminum, fully-wrapped steel or aluminum, all composite, carbon fiber. Cylinders are stamped with expiration date when then need recertified from 15 to 20 years. Most fumigation diesel/cng conversions are for off road use only, as far as emissions certifications on the mechanical system goes. Deluca states that his new electronic system will be emission compliant. http://www.delucafuelproducts.com/  I interviewed a school bus company owner that tried CNG a decade ago. In a test trip cross country found different CNG fill nipples in each state. They had to wait while the next nipple came to them UPS. Now there are just two nipples at fill stations across the country, fleet size and public size.

Normal driving, diesel/cng conversion kits lower boost and EGT's (exhaust gas temperature), but just like a programmer, drive hard, tow big trailers in the mountains and you can increase EGT heat. More power produces heat. As with engine power modifications, you should add an EGT gauge to your truck with a diesel/cng conversion. When we first installed the diesel/cng conversion kit on our 2006 Ford F250, the clutch did slip a couple of times. Figuring it was caused by the extra power, it hasn't happened since. Even though we are pleased with our CNG volume setting, occasionally driving in town at lower rpm's will produce some surging.

Installation in a Ford F250 Power Stroke Diesel below. I inspected the same system in GM Duramax diesel and Dodge Cummins diesel.

We drilled a hole in the plastic intake housing in front of the turbo. Venturi tube is as deep as the intake tube. The tube holes where the gas is drawn in by the turbo and mixed with air. The engine compartment is clean with just the fumigation CNG tube and heater hose showing.
Feeding the cng hose and heater hose by the firewall back to the cng tanks. Heater hose for keeping the regulator from freezing and fumigation tube for the intake. Wiring in the switch to turn on the regulator, fused into the truck's wiring. Steel tanks are heavy and cheap, eventually will get carbon fiber tanks.

Two 10 gallon tanks, secure in the bed. The regulators, fill nipple and pressure gauge are tucked out of the way with just a short pressure hose. An advantage over having the regulators in engine compartment. 3000 psi and 3600 psi pumps, more gallons with higher pressure. Very simple fill procedure, nipple like an air compressor coupler.

 Here is a chart on alternative fuel fill stations across the country.

STATE

BD

CNG

E85

ELEC

HY

LNG

LPG

Totals
by State

Alabama

16

3

6

0

0

0

46

71

Alaska

0

1

0

0

0

0

10

11

Arizona

10

40

19

5

1

5

50

130

Arkansas

2

3

6

0

0

0

37

48

California

37

183

10

370

25

28

199

852

Colorado

22

20

56

2

0

0

55

155

Connecticut

1

9

2

3

1

0

16

32

Delaware

3

1

1

0

0

0

3

8

Dist. of Columbia

1

1

3

0

1

0

0

6

Florida

12

15

15

3

2

0

47

94

Georgia

28

18

28

0

0

0

37

111

Hawaii

7

0

0

4

1

0

3

15

Idaho

6

7

4

0

0

1

25

43

Illinois

4

17

186

1

1

0

54

263

Indiana

6

13

110

0

0

0

28

157

Iowa

5

0

95

0

0

0

24

124

Kansas

5

2

24

0

0

0

44

75

Kentucky

1

0

11

0

0

0

13

25

Louisiana

1

5

3

0

0

0

10

19

Maine

5

1

0

0

0

0

8

14

Maryland

6

14

12

0

0

0

13

45

Massachusetts

7

11

1

18

0

0

23

60

Michigan

17

14

58

0

7

0

69

165

Minnesota

1

1

353

0

0

0

30

385

Mississippi

5

0

2

0

0

0

34

41

Missouri

8

7

77

0

1

0

75

168

Montana

4

3

2

0

0

0

31

40

Nebraska

3

2

36

0

0

0

18

59

Nevada

14

11

17

0

2

0

28

72

New Hampshire

11

3

1

8

0

0

11

34

New Jersey

0

11

0

0

0

0

10

21

New Mexico

7

10

7

0

0

0

49

73

New York

5

92

15

1

1

0

29

143

North Carolina

66

12

13

0

0

0

44

135

North Dakota

0

4

26

0

0

0

14

44

Ohio

22

8

61

0

0

0

66

157

Oklahoma

6

51

5

0

0

0

64

126

Oregon

36

12

8

9

0

0

29

94

Pennsylvania

6

26

19

0

1

0

63

115

Rhode Island

0

7

0

2

0

0

4

13

South Carolina

73

4

71

0

0

0

20

168

South Dakota

0

0

79

0

0

0

17

96

Tennessee

48

4

22

0

0

0

52

126

Texas

54

17

35

1

0

4

497

608

Utah

7

62

5

0

0

0

22

96

Vermont

2

1

0

2

1

0

5

11

Virginia

12

9

6

1

1

0

19

48

Washington

35

14

12

0

0

0

52

113

West Virginia

1

2

3

0

0

0

7

13

Wisconsin

3

19

113

0

0

0

45

180

Wyoming

14

8

6

0

0

0

26

54

Totals by Fuel:

645

778

1644

430

46

38

2175

5756

I'm planning my next horse expo tour trip to Missouri today, just went on www.cngprices.com and used their "Trip Planner" and found the CNG fill stations on the way. The new way to travel, plan your fuel route along with your highway route. I hope this isn't the end of the story as we need a national energy plan and CNG has promise. I still remember when the Alaskan Pipeline was going to save us a few decades ago. Look up sometime where the Alaskan pipeline oil goes. 

Important websites for more on CNG

http://www.myphill.com/                                                     http://www.pickensplan.com/

http://www.cngprices.com/                                                 http://www.ngvglobal.com/   

http://www.ngvamerica.org/           US Energy Stations Map

Tax Incentives            CNG Forums