# Presentation: 838920

## Natural Gas as aTransportation Fuel

- Benefits, Challenges, and Implementation
- 3/03/2008

## What Is Natural Gas?

- A combustible, gaseous mixture of simple hydrocarbon compounds, primarily methane
- Usually extracted from gas and oil wells. Smaller amounts are derived from supplemental sources such as landfill gas and coal-derived gas. Large deposits exist in more than half of the 50 states.
- Classified as an alternative fuel by the Energy Policy Act of 1992
- Accounts for 22% of U.S. energy use and 2.2% of energy used for U.S. transportation
- Source: EIA’s Annual Energy Review 2006, Table 1.3 and DOE’s Transportation Energy Data Book (edition 26) Table 2.2

## Natural Gas Vehicles

- 120,500 natural gas vehicles on U.S. roads in 2004
- 98.3K in private (fleets and consumers)
- 10.7K in state fleets
- 11.4K in federal fleets
- Source:  EIA, Alternatives to Traditional Transportation Fuels 2005, Table V9 and V13.

**Notes:**
Updated to 2005.  Next data release in May 2008

## Natural Gas Fueling Stations

- More than 825 natural gas fueling stations in the United States:
- 35 LNG
- 790 CNG
- 355 Public
- 470 Private
- Source:  DOE AFDC, Feb 2008

## Types of Natural Gas for Vehicles

**Compressed natural gas (CNG):**
- 	Generally** **used in vehicles at
- 	3000-3600 psi (household natural gas pipe pressure is ~1-2 psi)
**Liquefied natural gas (LNG): **
-     Made by lowering the temperature of CNG until it becomes a liquid

|      Equivalent Energy Content |  |
| --- | --- |
| 1 gal. gasoline | 1 gal. diesel |
| 118 scf CNG | 130 scf CNG |
| 1.6 gal. LNG | 1.7 gal. LNG |

**Notes:**
Compressed Natural Gas
To provide adequate driving range, CNG must be stored onboard a vehicle in tanks at high pressure—up to 3,600 pounds per square inch. A CNG-powered vehicle gets about the same fuel economy as a conventional gasoline vehicle on a gasoline gallon equivalent (GGE) basis. A GGE is the amount of alternative fuel that contains the same amount of energy as a gallon of gasoline. A GGE equals about 5.7 lb (2.6 kg) of CNG.
Liquefied Natural Gas
To store more energy onboard a vehicle in a smaller volume, natural gas can be liquefied. To produce LNG, natural gas is purified and condensed into liquid by cooling to -260°F (-162°C). At atmospheric pressure, LNG occupies only 1/600 the volume of natural gas in vapor form. A GGE equals about 1.5 gallons of LNG. Because it must be kept at such cold temperatures, LNG is stored in double-wall, vacuum-insulated pressure vessels. LNG fuel systems typically are only used with heavy-duty vehicles.

## Why Use Natural Gas Vehicles (NGVs)?

- Increased Energy Security
- Natural gas is a domestically available fuel
- Public Health and Environment Protection
- 80% less particulate matter
- 21-25% less greenhouse gas emissions

**Source: Wang, M.Q. and H.S. Huang, *****A Full Fuel-Cycle Analysis of Energy and Emissions Impacts of Transportation Fuels Produced from Natural Gas, *****December 1999.**

## Greenhouse Gas and Oil Use Comparison

- Source:
- www.eere.energy.gov/afdc/data/
- fuels.html

## Light Duty NGVs 

- Use CNG
- Limited to one model (Honda Civic) for OEM vehicles
- EPA certified conversions available from a variety of companies
- Home refueling devices

## Heavy Duty NGVs

- May use LNG or CNG
- Larger engines typically use LNG
- OEM engines available from Cummins-Westport
- EPA certified re-power engines and conversions available from a variety of companies

## Natural Gas Transit Buses

- Most established natural gas niche market
- Annual consumption (2006): 109 million diesel gallon equivalent of natural gas
- 15% of transit vehicles in 2006 powered by natural gas
- Source:  USDOT-FTA Alternative Fuels Study, December 2006 and APTA 2007 Vehicle Survey

## Other Heavy Duty NGVs

- Shuttle buses
- Trolleys
- Street sweepers
- Delivery trucks
- Refuse haulers
- Utility trucks
- Fork lifts

## Natural Gas Guides

- Heavy Vehicle and Engine Resource Guide
- 	- http://www.eere.energy.gov/afdc/pdfs/hvrg.pdf
- Available Natural Gas Vehicles and Engines
- 	- _[www.cleanvehicle.org/Available-NGVs-and-Engines.pdf](http://www.cleanvehicle.org/Available-NGVs-and-Engines.pdf)_

## Implementation Challenges  for Natural Gas

**Vehicle Price** – Natural gas vehicles cost more because of onboard fuel storage and engine modifications.
- NGV prices range from $4000 for LDV to $35,000 for transit bus to over $50,000 for specialty HDV
**Fuel Availability** – Refueling is less readily available outside of California; most fleets build their own infrastructure.

## Implementation Challenges  for NG

**Operating Costs** – Results vary by fleet.
- Washington Metro Area Transit Authority study of 40 ft. transit buses showed increased operating costs of 3 to 8 cents per mile.
- UPS study of delivery trucks showed increased operating costs of 19% for CNG in one fleet and decreased CNG operating costs, when compared to diesel, of 2% in a second fleet.
**Vehicle and Engine Availability**
- There is limited availability of OEM engines and vehicles.

- Source:  Washington Metropolitan Area Transit Authority: Compressed Natural Gas Transit Bus Evaluation
- www.nrel.gov/vehiclesandfuels/ngvtf/pdfs/37626.pdf) and
- UPS CNG Truck Fleet, Final Report, www.nrel.gov/vehiclesandfuels/fleettest/pdfs/31227.pdf

**Notes:**
WMATA:  Total Operating Costs. The total operating costs for the study buses were similar. The fuel costs
for CNG and diesel during the CNG bus evaluation periods were the same at $1.33/DGE. The
total operating costs were as follows: diesel, $1.06/mile; CWI CNG, $1.09/mile; and Deere
CNG, $1.14/mile. The major contributing factors are the fuel costs and fuel economy. Significant
changes in the fuel cost or fuel economy would change total operating costs significantly.

UPS:  Total operating costs for the CNG trucks
at Hartford were 19% higher than for
the diesel trucks; at Waterbury they
were 2% lower.
Maintenance costs for CNG trucks at
Hartford were 29% higher than for
diesel trucks because of troubleshooting,
replacement of spark plugs and
wires, and clutch and transmission
repairs. At Waterbury, the CNG costs
were 6% lower because of greater use
and longer preventive maintenance
inspection cycles.

## Federal Tax Incentives for NGVs

**Vehicle Tax Credits**
- 	(for new or retrofits)
- Light Duty (up to 8,500 lb):  up to $5,000
- Medium Duty (up to 14,000 lb):  up to $10,000
- Medium-Heavy Duty (up to 26,000 lb):  up to $25,000
- Heavy Duty (more than 26,000 lb):  up to $40,000

## Federal Tax Incentives for Fuel and Infrastructure

- Fuel Excise Tax Credits
- Fifty cents per gasoline-gallon equivalent of CNG or LNG
- Infrastructure Tax Credit
- 30% of cost of infrastructure
- Up to $30,000 per commercial project
- Up to $1,000 for home refueling appliance.

## For More Information

- Alternative Fuels Data Center
- www.eere.energy.gov/afdc/fuels/natural_gas.html
- www.eere.energy.gov/afdc/vehicles/natural_gas.html
- NGV America
- www.ngvc.org
- Clean Vehicle Education Foundation
- _[www.cleanvehicle.org/index.shtml](http://www.cleanvehicle.org/index.shtml)_

**Notes:**
Double-check these links