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Introduction. Propane is one of the world’s most common engine fuels Stations available worldwide High energy density Exceptionally safe U.S. imports about half of its petroleum Two thirds of petroleum is used for transportation Propane use offsets petroleum imports. Lesson 1:
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Introduction • Propane is one of the world’s most common engine fuels • Stations available worldwide • High energy density • Exceptionally safe • U.S. imports about half of its petroleum • Two thirds of petroleum is used for transportation • Propane use offsets petroleum imports
Lesson 1: Introduction to Propane
Objectives • Describe what propane (LPG) is and how to identify it • Explain the basic history of propane • Describe how propane may help public health and the environment • Explain how propane may help stimulate the economy • Describe what energy security is and how to use propane to attain it
Definition of Propane • Propane is: • Identified as an alternative fuel • Colorless • Odorless • Product of natural gas production and crude oil refining Figure 1: Propane molecule. Source: NAFTC.
Propane usually contains: • More than 90% propane • Some butane • Trace gases • Easily converted and stored as a liquid under pressure • Can produce fewer emissions than conventional gasoline • Presents no immediate environmental threats
Chemical Properties of Propane • Gas at ambient temperatures; liquid below -40°F or when under pressure • One cubic foot of liquid = 270 cubic feet of vapor Figure 2: Propane tanks. Source: NAFTC.
Specific Gravity • Specific gravity of liquid propane = 0.504 (half that of water) • Specific gravity of propane vapor = 1.50 (one and a half times as much as water) • Leaked propane vapors will sink to the floor Figure 3: The specific gravity of liquid propane is less than water, and the specific gravity of propane vapor is greater than air. Source: NAFTC.
Propane Color • Colorless liquid or vapor • Produces pale blue flame when ignited Propane Smell • Naturally odorless • Odorants are added to aid in leak detection
Propane Identification • Colorless, odorless; best identified by added odorants • Highly volatile; burns twice as hot as conventional gasoline Forms of Propane • Naturally occurs as a gas • Liquid quickly evaporates • Liquid is less flammable, less dangerous Figure 4: Propane flame. Source: NAFTC.
Propane Gas • Heavier than air • Tanks are usually pressurized up to around 300 psi or less Liquefied Petroleum Gas (LPG) • One gallon of liquid petroleum has about 75% as much energy as one gallon of conventional gasoline • Liquid propane injection systems can return higher fuel efficiency than conventional gasoline ICEs
Basic History of Propane • Used as an alternative fuel for more than 60 years • Dr. Walter Snelling first discovered propane in 1910 • Propane was used for cooking as early as 1912 • First propane powered car introduced in 1913 • Original applications were mostly farm equipment Figure 5: Propane gas tank. Source: NAFTC.
Used as a fuel for indoor vehicles beginning in the 1950s • RV industry relies on propane heavily • Propane = $10 billion industry in the U.S. alone Figure 6: Propane warehouse equipment. Source: NAFTC.
Less than 2% of U.S. propane consumption is used as a transportation fuel. Source: AFDC, 2011.
Propane Today • U.S. consumes more than 15 billion gallons of propane annually • 8.1 million households in the U.S. depend on propane • More than 270,000 vehicles in U.S. Figure 7: Ford E250 Roush CleanTech propane conversion. Source: AFDC.
Direct from the OEM, purpose-built vehicles utilize propane • Conversion vehicles have been converted from gasoline to utilize propane as a fuel source • Conversion kits are widely available for light-duty vehicles • Propane may be used in conjunction with gasoline for bi-fuel applications
Comparison of LPG to Gasoline • Propane is naturally gaseous • Fuel economy is calculated in gasoline gallon equivalent (GGE) • Propane = high octane fuel
Energy Content • Energy content is measured in British thermal units (Btu) • Propane = 47% more energy by mass when compared to gasoline Octane Rating • Indicates how well the fuel combusts, resistance to auto ignition • Conventional gasoline octane rating = 87, 89, 93 • Propane octane rating = around 105
Auto-Ignition Temperature • Propane’s auto-ignition temperature = 855°F (457°C) • Auto ignition requires between 2.15% and 9.6% propane in the air
Why Consider Propane? • Can produce fewer emissions than conventional vehicles • High energy output • High octane = more complete combustion • Propane generally costs about the same as gasoline and diesel
Figure 9: LPG compared to conventional gasoline. Source: fueleconomy.gov.
Propane Benefits • Propane = domestic resource • 90% of propane used in the U.S. is produced domestically • Promotes energy security • Established infrastructure • Longer vehicle service life Figure 10: Propane production. Source: EERE.
Health Benefits • Combustion can produce fewer harmful emissions like: • Particulate matter • Carbon monoxide (CO) • Fewer emissions = less smog formation = less respiration problems
Environmental Benefits • Propane vehicles can produce fewer harmful emissions • Spills rarely occur • If spilled, propane rapidly biodegrades in soil, water, air • Not considered a greenhouse gas (GHG) Figure 11: Propane vehicle emissions. Source: EERE.
Economic Benefits • Most accessible alternative fuel • Generally costs less than conventional fuels • Prices fluctuate seasonally – generally higher in the winter months (October through March)
Energy Security Benefits • U.S. imports more than 50% of its oil; two thirds is used for transportation • 97% of propane consumed in the U.S. is produced in North America, 90% in the U.S. alone • Propane use will help offset reliance on foreign oil supplies
Upon completing this lesson, can you: • Describe what propane (LPG) is and how to identify it? • Explain the basic history of propane? • Describe how propane may help public health and the environment? • Explain how propane may help stimulate the economy? • Describe what energy security is and how to use propane to attain it?
Test Your Knowledge • Propane burns with what color flame? • At normal temperatures, propane is a __________, but it can be liquefied under moderate pressure. • True or False: Propane gas is lighter than air. • True or False: Propane has been used as a fuel for home heating and cooking for decades.
Lesson 2: Propane Manufacturing, Infrastructure, and Sustainability
Objectives • Describe what propane is made from • Explain how propane is manufactured and produced • Describe how propane is transported • Explain how propane is distributed • Describe the sustainability of propane – its future and cost efficiency
Fuel Sources • Propane = byproduct of refining oil or natural gas • About half of the propane produced in the U.S. is from natural gas production, half is from crude oil refining • Propane is captured during these processes
Manufacturing and Production • Natural Gas Refining • Propane, butane, ethane are removed from raw natural gas • Natural gas = mostly methane; propane is heavier than methane • Raw natural gas is chilled • Propane condenses out of raw natural gas and is collected
Crude Oil Refining • Propane is removed through cracking • Oil is heated, lighter propane molecules evaporate and are collected • Propane boils at -44°F (-42.2°C) • One 42 gallon barrel of crude oil produces about 1.5 gallons of LPG
Figure 12: Propane as a percentage of refined crude oil. Source: DOE.
Transportation and Distribution • Stored and transported in large pressurized tanks • 56,000 miles of pipeline • More than 6,000 retail locations • Portable tanks enable delivery beyond pipelines • Can be transported via rail, pipeline, barge, truck Figure 13: Multiple propane storage tanks. Source: EERE.
Figure 14: Schematic of a typical propane distribution route. Source: EIA.
Transporters • Placards and/or other markings are required for all bulk shipments • Identified by number UN 1075 Figure 15: LPG transport placard UN1075. Source: USDOT, PHMSA.
Infrastructure • Nearly every city and town in the U.S. has a propane fueling station/propane source • Nationwide infrastructure is already in place
As of February 2012, the total number of U.S. LPG fueling stations was at 2,670. This is more than the 2,512 E85 stations. Source: AFDC.
LPG Fueling Stations • Many items are the same/similar to conventional fueling stations • Most tanks are steel • Certain materials must be used to prevent premature wear Figure 17: Propane Fueling Station. Source: NREL.
LPG Fueling Station Safety Systems • Fueling station systems closely resemble conventional fueling stations • Similar safety precautions/devices are in place National Fire Protection Association (NFPA) Figure 18: NFPA 704 hazard placard for propane. Source: NAFTC.
Propane Sustainability • Propane is derived from fossil fuels • Propane can be utilized with minimal modification to vehicles • Propane is better for the environment than conventional fuels • Additional fueling stations must be built • Bi-fuel vehicles will assist in this development
Propane is the only alternative fuel with fueling stations located in every state. Source: AFDC.
The Future of Propane • Propane is the most widely used alternative fuel • Propane prices are historically below prices for conventional gasoline • Limited worldwide supply • Investigations are underway into producing synthetic propane
Upon completing this lesson, can you: • Describe what propane is made from? • Explain how propane is manufactured and produced? • Describe how propane is transported? • Explain how propane is distributed? • Describe the sustainability of propane – its future and cost efficiency?
Test Your Knowledge • Name two processes that are sources of propane. • True or False: Propane is the only alternative fuel that has a fueling station in every state. • Propane accounts for what percentage of products refined from crude oil? • True or False: LPG consumption is predicted to rise over the next few years.
Lesson 3: Propane Vehicles
