Environmental design in rail transportation

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Environmental design is an emerging topic in railroad technology. From the 1980s to 2009, fuel efficiency in diesel locomotives in the USA has increased 85%, [1] allowing these trains to go farther and move more freight while using less fuel. New low-impact electric and hybrid trains reduce overall carbon emissions. Also, train manufacturers have started utilizing hydrogen technology for propulsion, with carbon emissions only coming from the manufacturing of the hydrogen itself.

Contents

Increasing efficiency while lowering emissions

Diesel trains

Diesel Train Db-220002-01-c.jpg
Diesel Train

Diesel trains replaced the steam engine in the late 1920s as a cleaner more efficient way of moving people and goods. Since 1980, the amount of freight being hauled by Diesel Trains has nearly doubled, yet the fuel consumption of trains has virtually stayed the same. [1] Estimates have shown that about 170,000,000 cubic metres (45×10^9 US gal) of fuel have been saved by increasing the efficiency in diesel trains. US Department of Energy reported that commercial airline energy intensity was 2,352 kilojoules per kilometre (3,587 BTU/mi), automobiles were 2,327 kilojoules per kilometre (3,549 BTU/mi), while commuter rail energy intensity was just 1,804 kilojoules per kilometre (2,751 BTU/mi), which indicates that rail transportation is the most energy efficient of the three. The Union Pacific Rail Road has implemented a particle filter on their diesel engines. Silicon carbide blocks trap particles from the exhaust as they leave the engine, greatly reducing emissions. [2]

Electric trains

Electric trains have always had no direct carbon emissions because they are run entirely by internal electric motors. However, the means of generating the electricity used to power these motors was predominately by burning fossil fuels or coal, both of which produce a large amount of carbon emissions. With the emergence of 'clean energy' generation, electrical trains actually run with very low environmental impact. For example, the proposal for the high-speed rail line between San Francisco and Los Angeles in California has the potential for zero greenhouse gas emissions, with the 3,350 GWh each year being generated by California's extensive infrastructure of renewable energy sources. [3]

Hybrid trains

RailPower GG20B Green Goat diesel-hybrid locomotive. UNION PACIFIC Y2513 20070228.jpg
RailPower GG20B Green Goat diesel-hybrid locomotive.

Since 1986, engineers have been developing electric-diesel "hybrid" trains. One type of hybrid train implements battery power when the train is idling and at low speed movement, and a diesel engine at higher speeds. To recharge the batteries, power from the diesel motor, charge utilizing regenerative braking, or a combination of both is used. According to the Institute of Electrical and Electronics Engineers, hybrid trains reduce the carbon emissions of Diesel Trains by 19%. [4] Another type of hybrid train, such as the RailPower Technologies Green Goat, uses a large battery, and a small set of generators ("genset") for power. The genset is run at a constant speed and is attached to a generator to replenish the battery.

Hydrail

Hydrogen propulsion is an emerging technology, and is currently being implemented in locomotives. Hydrogen-powered trains dubbed "Hydrail" emit only water as a by product of combustion, and have a zero direct greenhouse gas emission. However, the process used to generate hydrogen in a form useful to power trains does produce a small amount of greenhouse gases. By using wind energy and electrolysis, 6.85 grams of greenhouse gases per MJ of LHV are produced, which is an insignificant amount compared to the 22 pounds of greenhouse gas emissions from one gallon of gasoline. [5] Trains are prime targets for hydrogen propulsion due to their ability to store massive tanks of hydrogen. [6]

Emissions comparison

Rail transportation emits about 0.2 pounds of greenhouse gases per passenger mile (55 g/km) when each car is filled with 50 passengers. This figure increases to about 0.5 pounds per passenger mile (140 g/km) when only filled with half that amount. These numbers are still much lower than those of Jet transportation, about 1 pound per passenger mile (280 g/km), and that of a solo car driver, about 1.15 pounds per passenger mile (325 g/km). Even the fuel efficient Prius emits more greenhouse gases per passenger mile. [7]

Estimates have shown that if just 10% of long-distance freight that is currently moving by truck were to be moved instead by diesel trains, the resulting carbon emission reduction would be the equivalent of taking 2 million cars off the road. [8] The results are more dramatic when the diesel train figures are replaced by hybrid and electric train figures.

See also

Related Research Articles

Engine Machine that converts one or more forms of energy into mechanical energy

An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy.

Hybrid vehicle Vehicle using two or more power sources

A hybrid vehicle is one that uses two or more distinct types of power, such as submarines that use diesel when surfaced and batteries when submerged. Other means to store energy include pressurized fluid in hydraulic hybrids.

A hydrogen vehicle is a vehicle that uses hydrogen fuel for motive power. Hydrogen vehicles include hydrogen-fueled space rockets, as well as ships and aircraft. Power is generated by converting the chemical energy of hydrogen to mechanical energy, either by reacting hydrogen with oxygen in a fuel cell to power electric motors or, less commonly, by burning hydrogen in an internal combustion engine.

Electric vehicle Vehicle propelled by one or more electric motors

An electric vehicle (EV) is a vehicle that uses one or more electric motors for propulsion. It can be powered by a collector system, with electricity from extravehicular sources, or it can be powered autonomously by a battery. EVs include, but are not limited to, road and rail vehicles, surface and underwater vessels, electric aircraft and electric spacecraft.

Fuel efficiency Form of thermal efficiency

Fuel efficiency is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical potential energy contained in a carrier (fuel) into kinetic energy or work. Overall fuel efficiency may vary per device, which in turn may vary per application, and this spectrum of variance is often illustrated as a continuous energy profile. Non-transportation applications, such as industry, benefit from increased fuel efficiency, especially fossil fuel power plants or industries dealing with combustion, such as ammonia production during the Haber process.

Alternative fuel Non-conventional yet reasonably viable fuels

Alternative fuel, known as non-conventional and advanced fuels, are any materials or substances that can be used as fuels, other than conventional fuels like; fossil fuels, as well as nuclear materials such as uranium and thorium, as well as artificial radioisotope fuels that are made in nuclear reactors.

Zero-emissions vehicle Class of motor vehicle

A zero-emission vehicle, or ZEV, is a vehicle that does not emit exhaust gas or other pollutants from the onboard source of power. The California definition also adds that this includes under any and all possible operational modes and conditions. This is because under cold-start conditions for example, internal combustion engines tend to produce the maximum amount of pollutants. In a number of countries and states, transport is cited as the main source of Greenhouse gases (GHG) and other pollutants. The desire to reduce this is thus politically strong.

Hydrogen fuel is a zero-carbon fuel burned with oxygen; provided that it is created in a process that does not involve carbon. It can be used in fuel cells or internal combustion engines. Regarding hydrogen vehicles, hydrogen has begun to be used in commercial fuel cell vehicles such as passenger cars, and has been used in fuel cell buses for many years. It is also used as a fuel for spacecraft propulsion.

Fuel cell vehicle Vehicle that uses a fuel cell to power its electric motor

fuel cell vehicle (FCV) or fuel cell electric vehicle (FCEV) is an electric vehicle that uses a fuel cell, sometimes in combination with a small battery or supercapacitor, to power its onboard electric motor. Fuel cells in vehicles generate electricity generally using oxygen from the air and compressed hydrogen. Most fuel cell vehicles are classified as zero-emissions vehicles that emit only water and heat. As compared with internal combustion vehicles, hydrogen vehicles centralize pollutants at the site of the hydrogen production, where hydrogen is typically derived from reformed natural gas. Transporting and storing hydrogen may also create pollutants.

Green vehicle

A green vehicle, clean vehicle, eco-friendly vehicle or environmentally friendly vehicle is a road motor vehicle that produces less harmful impacts to the environment than comparable conventional internal combustion engine vehicles running on gasoline or diesel, or one that uses certain alternative fuels. Presently, in some countries the term is used for any vehicle complying or surpassing the more stringent European emission standards, or California's zero-emissions vehicle standards, or the low-carbon fuel standards enacted in several countries.

Fossil fuel power station Facility that burns fossil fuels to produce electricity

A fossil fuel power station is a thermal power station which burns a fossil fuel, such as coal or natural gas, to produce electricity. Fossil fuel power stations have machinery to convert the heat energy of combustion into mechanical energy, which then operates an electrical generator. The prime mover may be a steam turbine, a gas turbine or, in small plants, a reciprocating gas engine. All plants use the energy extracted from the expansion of a hot gas, either steam or combustion gases. Although different energy conversion methods exist, all thermal power station conversion methods have their efficiency limited by the Carnot efficiency and therefore produce waste heat.

Monroney sticker Automobile label in the United States

The Monroney sticker or window sticker is a label required in the United States to be displayed in all new automobiles and includes the listing of certain official information about the car. The window sticker was named after Almer Stillwell "Mike" Monroney, United States Senator from Oklahoma. Monroney sponsored the Automobile Information Disclosure Act of 1958, which mandated the disclosure of equipment and pricing information on new automobiles.

Gasoline gallon equivalent (GGE) or gasoline-equivalent gallon (GEG) is the amount of an alternative fuel it takes to equal the energy content of one liquid gallon of gasoline. GGE allows consumers to compare the energy content of competing fuels against a commonly known fuel, namely gasoline.

A hybrid train is a locomotive, railcar or train that uses an onboard rechargeable energy storage system (RESS), placed between the power source and the traction transmission system connected to the wheels. Since most diesel locomotives are diesel-electric, they have all the components of a series hybrid transmission except the storage battery, making this a relatively simple prospect.

Alternative fuel vehicle Type of vehicle

An alternative fuel vehicle is a motor vehicle that runs on alternative fuel rather than traditional petroleum fuels. The term also refers to any technology powering an engine that does not solely involve petroleum. Because of a combination of factors, such as environmental concerns, high oil-prices and the potential for peak oil, development of cleaner alternative fuels and advanced power systems for vehicles has become a high priority for many governments and vehicle manufacturers around the world.

Marine propulsion Systems for generating thrust for ships and boats on water

Marine propulsion is the mechanism or system used to generate thrust to move a ship or boat across water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electric motor or engine turning a propeller, or less frequently, in pump-jets, an impeller. Marine engineering is the discipline concerned with the engineering design process of marine propulsion systems.

Energy efficiency in transport Discussing what form of transport is the most fuel efficient and economical.

The energy efficiency in transport is the useful travelled distance, of passengers, goods or any type of load; divided by the total energy put into the transport propulsion means. The energy input might be rendered in several different types depending on the type of propulsion, and normally such energy is presented in liquid fuels, electrical energy or food energy. The energy efficiency is also occasionally known as energy intensity. The inverse of the energy efficiency in transport, is the energy consumption in transport.

Environmental impact-minimizing vehicle tuning is the modification of cars to reduce energy consumption.

Hydrail

Hydrail is the generic adjective term describing all forms of rail vehicles, large or small, which use on-board hydrogen fuel as a source of energy to power the traction motors, or the auxiliaries, or both. Hydrail vehicles use the chemical energy of hydrogen for propulsion, either by burning hydrogen in a hydrogen internal combustion engine, or by reacting hydrogen with oxygen in a fuel cell to run electric motors. Widespread use of hydrogen for fueling rail transportation is a basic element of the proposed hydrogen economy. The term is used extensively by research scholars and technicians around the world.

The FV-E991 series (FV-E991系), nicknamed HYBARI, is a hydrogen fuel cell electric multiple unit (EMU) train type operated by East Japan Railway Company from 2022.

References

  1. 1 2 "AAR: Environment". Association of American Railroads. Archived from the original on January 27, 2010. Retrieved June 27, 2009.
  2. "UP: Environmental Management". Union Pacific Rail Road. Retrieved June 28, 2009.
  3. "Californias-220-MPH-high-speed-train". CleanTechnica.com. 15 September 2008. Retrieved June 27, 2009.
  4. "Thermo-Economic Analysis of Dual Mode Hybrid Trains: Abstract". Institute of Electrical and Electronics Engineers. doi:10.1109/ICCEP.2007.384191. S2CID   11938019.{{cite journal}}: Cite journal requires |journal= (help)
  5. "Recent Canadian Advances in Hydrail and Nuclear Based Hydrogen Production" (PDF). Hydrail. Retrieved June 27, 2009.
  6. "Hydrail: Hydrogen trains picking up steam?". Hydrail. Retrieved June 27, 2009.
  7. "How Low-Carbon Can You Go: The Green Travel Ranking". Sightline Institute. Retrieved December 9, 2014.
  8. "Green from the Start" (PDF). Association of American Railroads. Archived from the original (PDF) on January 28, 2016. Retrieved December 9, 2014.