TECHNOLOGIES PROGRAM

Propane Basics powers about 190,000 in the United States and more than 14 million worldwide.1 Propane vehicles are a good choice for many fleet applications, including school buses, shuttle buses, taxis and light-duty trucks. The advantages of propane as an alternative include its domestic availability, performance, safety, and clean-burning qualities.

What is propane? solely on propane and bifuel vehicles that have two separate fueling systems, which Also known as liquefied petroleum enable them to run on propane or gaso- gas (LPG), propane is an odorless, non- line. Vehicles can either be converted toxic hydrocarbon (C H ) gas at normal 3 8 to use propane or delivered as dedicated pressures and temperatures. When Lower maintenance costs are a prime propane vehicles directly through select pressurized, it is a liquid with an energy reason behind propane’s popularity for original equipment manufacturers’ high-use vehicles, such as school buses. density 270 times greater than its gas- (OEM) dealerships. Certified techni- Photo from Propane Education & Research Council eous form.2 A gallon of liquid propane cians can install U.S. Environmental has about 25% less energy than a gallon Protection Agency (EPA) and/or of . California Air Resources Board certified a mixer located near the intake manifold propane conversion systems on a variety where it is metered and combined with How is propane produced of vehicles. A list of certified systems filtered air before being drawn into the and distributed? can be found on the EPA Web site at combustion chamber and burned to pro- Propane is a byproduct of http://iaspub.epa.gov/otaqpub/publist1. duce power, just like a gasoline engine. processing and crude oil refining with jsp. Medium-duty propane vehicles and In a liquid-injected system, fuel is almost equal amounts of production heavy-duty propane engines are also delivered into the combustion chamber, derived from these sources. About 97% available. To find them, use the Heavy- or intake port, in a liquid form (instead of the propane consumed in the United Duty Vehicle and Engine Search on the of a vapor). This way, the fuel combusts States is produced in North America.3 Alternative and Advanced Vehicles more fully and provides optimal power Propane is shipped from its point of Data Center (AFDC) Web site at www. and throttle response. production to bulk distribution terminals afdc.energy.gov/afdc/vehicles/heavy. via pipeline, railroad, barge, truck, or How do propane tanker. Propane marketers fill trucks at How do propane vehicles perform? the terminals and distribute the fuel to vehicles work? Propane vehicles are similar to their end users, such as retail fueling stations. Propane vehicles operate much like gaso- gasoline counterparts with regard to line vehicles with spark-ignited engines. power, acceleration, and cruising speed. Is propane safe for There are two types of fuel-injection The driving range of bifuel vehicles is vehicle use? systems available: vapor and liquid injec- comparable to that of gasoline vehicles, Yes. Propane vehicles must meet the tion. In both types, propane is stored and the fuel economy of dedicated same safety standards as gasoline as a liquid in a relatively low-pressure propane vehicles is slightly lower due to vehicles and have passed rigorous crash tank (about 300 psi). In a vapor-injected propane’s lower energy content. Larger testing. In addition, propane has a nar- system, liquid propane is controlled by storage tanks can increase range, but row flammability range, and its tanks are a regulator or vaporizer, which converts the additional weight displaces payload 20 times more puncture-resistant than the liquid to a vapor. The vapor is fed to capacity. gasoline tanks. ———————————————————— 1 World LP Gas Association 2009 (http://worldlp- Are propane gas.com/gain/key-autogas-data) vehicles available? 2 Energy Information Administration Web site (www.eia.doe.gov) Yes, two types of propane vehicles are 3 Propane Education & Research Council Web site available: dedicated vehicles that run (www.usepropane.com/climate)

www.cleancities.energy.gov • March 2010 VEHICLE TECHNOLOGIES PROGRAM • March 2010 • Page 2

local propane marketer to establish new fueling infrastructure at little to no cost depending on the fuel contract and the complexity of the equipment being installed.

Is it easy to fuel a propane vehicle? Filling a propane vehicle is similar to fueling a conventional vehicle and takes about the same amount of time. In addi- tion, spillage and ground contamination are not concerns with propane because any fuel that might escape dissipates into According to the AFDC Stations Count, there are more than 2,400 LPG stations available the air quickly and harmlessly. As with all to fuel the country’s more than 270,000 propane vehicles. vehicles, however, proper safety precau- tions—such as no smoking or cell phone How much do propane success, fleets should develop relation- use—must be recognized when refueling vehicles cost? ships with their local propane marketers a propane vehicle. and station operators who can provide OEM delivered light-duty propane them with the fair pricing and help them How do propane vehicle vehicles can cost several thousand dol- establish onsite infrastructure at little lars more than comparable gasoline or no cost if a fuel contract is executed. emissions compare vehicles. However, federal tax credits When fleets fuel their vehicles at loca- with gasoline vehicle may offset the increased vehicle cost and tions where there is no relationship with emissions? many states have additional incentives the fuel marketer or station operator, that further incentivize the purchase of Compared with gasoline vehicles, the fuel price may be equal to or higher propane vehicles produce significantly a propane vehicle. Vehicle conversions than gasoline. Local propane marketers may also qualify for tax credits and other lower , nitrogen oxide, are present in most every community hydrocarbon, particulate matter, and incentives. For the latest information on across the United States and can provide incentives for both OEM and converted greenhouse gas emissions. In addition, expertise and technical assistance in propane is not a greenhouse gas when vehicles, visit the Federal and State establishing infrastructure. Incentives and Laws section of the released directly into the atmosphere. AFDC at www.afdc.energy.gov. Tax credits and incentives may also be available that can help reduce the cost of Where can I learn more Lower maintenance costs are a prime propane. For more information, see the about propane? reason behind propane’s popularity for AFDC’s Federal and State Incentives and To learn more about propane as a trans- high-mileage vehicles. Propane’s high Laws section at www.afdc.energy.gov. portation fuel, visit the AFDC’s Propane (104 to 112 compared with Fuels and Vehicles sections (www.afdc. 87 to 92 for gasoline) and low-carbon and energy.gov), contact your local Clean oil-contamination characteristics have Where is propane Cities coordinator (www.cleancities.energy. resulted in documented engine life of up available? gov), or visit the Propane Education & to two times that of gasoline engines.4 Propane is widely available. According Research Council (www.propanecouncil. to the AFDC, there were more than org), and the National Propane Gas 2,400 propane stations in the United How much does Association (www.npga.org) Web sites. propane cost? States as of February 2010. To find propane station locations in your area, The price of propane is typically based visit the Alternative Fueling Station on the volume of fuel used. For the best Locator on the AFDC Web site at www. ———————————————————— afdc.energy.gov/stations. As previously 4 AFDC (www.afdc.energy.gov/afdc/vehicles/ mentioned, fleets can work with their propane_what_is.html)

Clean Cities Technical Response Service Prepared by the National Renewable Energy Laboratory 800-254-6735 (NREL), a national laboratory of the U.S. Department of [email protected] Energy, Office of Energy Efficiency and Renewable Energy; NREL is operated by the Alliance for Sustainable Energy, LLC.

DOE/GO-102010-2948 • March 2010 CLEAN CITIES CLEAN