Propane Power LPG Vehicles

Transcription

1 Propane Power LPG Vehicles Information from fuels/

2 How Liquefied Petroleum Gas Works Liquefied petroleum gas, or LP gas, (LPG) is becoming a common alternative fuels used in the world today. In fact, in many places, it isn't an alternative fuel at all: LP gas is a mainstay for heating and cooking in certain areas of India and some rural areas of the United States. When you cook out at a campground or in your backyard using a gas grill or camping stove, you're using some form of LP gas. Known for its versatility and efficiency, these days LP gas is looking like an attractive source of energy for people fed up with high heating bills and skyrocketing prices at the pump.

3 What is Liquefied Petroleum Gas (LPG)? There are two LP gases that can be stored in liquid form with only moderate pressurization propane and butane. Isobutane, which has the same simple chemical formula as butane but has a different chemical structure, is also used. Usually, butane and isobutane are mixed with propane in various proportions, depending on the intended use of the fuel.

4 What is Liquefied Petroleum Gas (LPG)? Propane is particularly useful as a portable fuel because its boiling point is 44 F ( 42 C). That means that even at very low temperatures, it will vaporize as soon as it is released from its pressurized container. This results in a clean burning fuel that doesn't require a lot of equipment to vaporize it and mix it with air. A simple nozzle will suffice. Butane's boiling point is approximately 31 F ( 0.6 C), which means it will not vaporize in very cold temperatures. This is why butane has more limited uses and is mixed with propane instead of being used by itself. A single pound of propane can generate 21,548 BTU (British Thermal Units) of energy, while butane can produce 21,221 BTU per pound [ref]. For comparison, here is how LP Gases stack up to other fuels in terms of energy: Propane: 21,500 BTU per pound Butane: 21,200 BTU per pound Gasoline: 17,500 BTU per pound Coal: 10,000 BTU per pound Wood: 7,000 BTU per pound

5 The Source of LPG? LP gas is a fossil fuel, like oil and natural gas. It can be refined from oil and natural gas the same way gasoline is refined from crude oil. While most energy companies are not focused on LP gases, they produce them nonetheless because they are a byproduct of the refining process for other fuels. When an energy company draws natural gas from the ground, about 90 percent of it is methane. The rest is in the form of various LP gases, which the company separates from the methane before the methane is fed into pipelines for use in our homes. The amount of LP gas that comes from natural gas varies, but it is usually from 1 to 3 percent. LP gases are separated from crude oil, as well. The refining process produces about a 3 percent yield of LP gases, although if refineries were retooled to focus on LP gas extraction, that number could be as high as 40 percent.

6 An Interesting Side Note about The Source of LPG. The Discovery of LP Gas Initially, the natural gas industry had problems with the "extra" compounds contained in the gas. The propane and butane was unstable, evaporated easily and created higher vapor pressures when storing and transporting natural gas. The first solution was to simply "weather" the natural gas, allowing the LP gases to boil off into the atmosphere. Dr. Walter Snelling, an inventor and scientists who worked for the U.S. Geological Survey, began experimenting with the condensed forms of these waste materials in By 1911, he had produced samples of propane and butane and had already envisioned a storage and distribution system for these fuels. In 1913, he was granted a patent or his method of producing LP gases.

7 LPG A Versatile Fuel LP gas is easy and safe to store, which makes it a very portable fuel. It has been utilized for many different applications, some of which you've probably used yourself. Small, disposable butane lighters use the LP gas you are most likely to see on a daily basis. They contain a mixture of butane and isobutane. If you have a portable gas grill, or if you go camping in a trailer or motor home, you use LP gas there, as well. The nozzles on the tanks have been standardized throughout the camping industry, so these tanks can be attached to camp stoves, lanterns, and a variety of other devices. Propane is useful in any situation where fuel is needed but it's not practical (or possible) to run lines for natural gas to the site. You can find LP gas on boats, at isolated cabins and hunting lodges or in rural areas that aren't served by commercial energy companies. In countries like India, where some large cities do not have reliable natural gas or other fuel service, LP gas makes up a major share of the energy market. Everyday heating and cooking needs are supplied by propane instead of oil or coal.

8 LPG A Versatile Fuel LP gas isn't only for home and leisure use, however. Many industries use LP gas as a source of heat for metal working, glass working or ceramics. Many industrial forklifts are LP gas powered because LP gas provides enough power to do heavy lifting while generating reduced fumes and pollutants in confined warehouse spaces. One of the fastest growing uses of LP gas is in automobiles. Cars built or converted to run on LP gas are becoming more and more common.

9 Autogas According to the World Liquefied Petroleum Gas Association (WLPGA), more than 9 million vehicles in 38 countries currently operate on LP gas. It's not a new idea: Propane powered vehicles have been around for decades. The benefits include reduced emissions, quoted by WLPGA as "50% less carbon monoxide, 40% less hydrocarbons, 35% less nitrogen oxides (NOx) and 50% less ozone forming potential compared to gasoline". With government incentives and tax breaks figured in, LP gas used in cars (known as autogas) can be much cheaper than gasoline. Even without the incentives, it is usually much cheaper. Autogas is a high octane fuel, offering performance comparable to gasoline and diesel, and many owners claim that autogas runs more smoothly, resulting in less wear and tear on engine components.

10 Autogas The easiest way to start using propane for transportation is to buy a vehicle that was designed and built to use autogas. A wide range of manufacturers, including major American car companies like Ford, General Motors and Daimler Chrysler, offer propane powered options on some models. Typically, you won't find these cars on the showroom floor they have to be special ordered. In some cases, there is no production model powered by LP gas, but an LPG system can be factory installed as an option. Examples of cars that are offered as LP gas models include the Ford Crown Victoria, Dodge Ram, Ford F 150 truck, Chevrolet Cavalier and Toyota Camry.

11 Autogas Rarely (though more often in Europe), cars are built solely with an LP gas fuel system. The engine is tuned and adjusted specifically to run at maximum efficiency on propane, which results in reduced engine wear and better mileage in the long run. However, many consumers are worried that a propane filling station could be hard to find. For that reason, most LP gas cars have dual fuel systems one for gasoline and one for propane. The systems are set to switch automatically between the two fuels as appropriate. This allows owners to use clean, cheap propane when it's available, but they still have the option of a quick fill up at the local gas station if they need it.

12 Autogas How hard is it to find a propane filling station? Actually, it's not very difficult at all. Unlike some other alternative fuels (such as hydrogen), a large and stable infrastructure already exists for vehicles running on propane. You can use the Alternative Fuels Data Center to find the nearest LP gas refueling stations. As an example, there is one right here in Romeo.

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14 Autogas Fueling a vehicle with Autogas is just like fueling your vehicle with traditional gas.

15 Conversion to Autogas The process of converting a car to run on propane is fairly demanding and requires a good knowledge of automotive systems in general to accomplish. Several companies offer kits that include all the needed parts to perform the conversion. Those without the necessary knowhow should try to find a local mechanic with experience in LPgas conversions to get the job done. Although propane is very safe as an automotive fuel, if the system is not installed correctly, there can be safety problems.

16 Conversion to Autogas The first step is choosing a tank. Most conversions are dual fuel conversions, meaning you won't be replacing your old fuel system, you'll simply be adding a second. As a result, the propane tank will take up some of the storage space in your car, usually in the trunk. Donut tank (left) and torpedo tank (right). Tanks come in "torpedo" or "donut" form. Torpedo tanks generally have more capacity, but will take up more space in your car. Donut tanks are designed to fit in the spare tire well of your car. They are smaller tanks, and you'll have to sacrifice your spare tire. In larger vehicles, you could mount multiple tanks for increased capacity.

17 Conversion to Autogas Once the tank is bolted in, a fill point must be drilled into the car's body, usually near the gasoline fill point or at the back of the trunk. The ideal location is one that requires minimal piping to connect to the tank. The fuel lines themselves are copper tubes, which offer a certain amount of flexibility when the lines are routed. The tank must be connected to the fill point, and lines also have to run along the underside of the car up to the engine. A solenoid valve LPG valve must be installed on the fuel line in between the tank and the engine. This valve cuts the flow of LP gas when the car is running on gasoline and when the engine is shut off. It also has a filter built in that removes any dirt that may be in the fuel.

18 Conversion to Autogas The next major component is called a regulator, also referred to as a vaporizer. This device performs one of the functions that a carburetor handles in a gasoline engine it uses heat from the car's cooling fluids to vaporize the propane into gas form. Another safety check occurs at the regulator, as well. It includes an electronic circuit that cuts the flow of gas if the engine stops or stalls. The regulator is usually smaller than a regular carburetor, so finding space for it in the engine compartment shouldn't be a problem. The other part of a carburetor's function is handled by a mixer mounted in the intake manifold. The mixer takes information from the car's sensors or ECU, and then it controls the amount of gas that flows into the cylinders

19 Conversion to Autogas Dashboard fuel switch/gauge The system must then be wired into the car's electrical system, allowing for a functioning fuel gauge, as well as proper automatic switching between propane and gasoline (along with a dashboard mounted manual switch). There must be connections to the car's ECU so that the engine controller can adjust for different fuel settings. Cars with an electronic injection system will probably need an electronic emulator. When the car is operating on LP gas, the fuel injectors will not be sending any information to the other sensors in the car this will light up the "check engine" light and give incorrect diagnostic readings. The emulator fakes the proper signals so the ECU can operate properly. Conversion kits come with more detailed instructions, but this is a basic overview of what needs to happen in a dual fuel conversion.

20 Safety and Storage of Autogas LP gases are actually quite safe in comparison with other fuels. Propane has a high ignition temperature, about F ( C) compared to about 495 F (257 C) for gasoline. This makes it less likely to ignite spontaneously. Also, the tanks used to store propane are stronger than gasoline tanks because of the pressure needed to keep the propane in liquid form. This makes on board propane storage safer than a typical gas tank it is more resistant to rupturing in the event of a collision. Special safety valves and cut offs increase the safety factor.

21 Safety and Storage of Autogas To store LP gas safely, there are some guidelines. It's important to remember that a propane tank is never really empty. When the tank is filled, most of the propane is under enough pressure that it is in liquid form. But at safe pressures, not all of the propane is liquefied a small amount is in gas form, filling up the rest of the space in the tank. As more propane is used, the pressure decreases, leaving less propane in liquefied form and more propane gas filling up the remaining space. Tanks should only be filled to roughly 80 percent capacity. Changes in temperature can change the pressure inside the tank. If you were to fill your tank to 100 percent on a cool, cloudy day, and then leave your car out in the sun the next day, the increase in temperature would cause in increase in pressure within the tank that could cause it to fail without that 20 percent headroom.

22 Case Study Videos on Autogas