Environmental design in rail transportation

Last updated

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

<span class="mw-page-title-main">Engine</span> Machine that converts one or more forms of energy into mechanical energy (of motion)

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

<span class="mw-page-title-main">Fuel cell</span> Device that converts the chemical energy from a fuel into electricity

A fuel cell is an electrochemical cell that converts the chemical energy of a fuel and an oxidizing agent into electricity through a pair of redox reactions. Fuel cells are different from most batteries in requiring a continuous source of fuel and oxygen to sustain the chemical reaction, whereas in a battery the chemical energy usually comes from substances that are already present in the battery. Fuel cells can produce electricity continuously for as long as fuel and oxygen are supplied.

<span class="mw-page-title-main">Hybrid vehicle</span> 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.

<span class="mw-page-title-main">Hydrogen vehicle</span> Vehicle that uses hydrogen fuel for motive power

A hydrogen vehicle is a vehicle that uses hydrogen to move. Hydrogen vehicles include some road vehicles, rail vehicles, space rockets, forklifts, ships and aircraft. Motive 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 hydrogen internal combustion.

<span class="mw-page-title-main">Electric vehicle</span> Vehicle propelled by one or more electric motors

An electric vehicle (EV) is a vehicle that uses one or more electric motors for propulsion. The vehicle can be powered by a collector system, with electricity from extravehicular sources, or can be powered autonomously by a battery or by converting fuel to electricity using a generator or fuel cells. EVs include road and rail vehicles, electric boats and underwater vessels, electric aircraft and electric spacecraft.

<span class="mw-page-title-main">Fuel efficiency</span> 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.

<span class="mw-page-title-main">Zero-emissions vehicle</span> 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.

<span class="mw-page-title-main">Fuel cell vehicle</span> Vehicle that uses a fuel cell to power its electric motor

A 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. 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. Fuel cells have been used in various kinds of vehicles including forklifts, especially in indoor applications where their clean emissions are important to air quality, and in space applications. Fuel cells are being developed and tested in trucks, buses, boats, ships, motorcycles and bicycles, among other kinds of vehicles.

<span class="mw-page-title-main">Green vehicle</span> Environmentally friendly vehicles

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.

<span class="mw-page-title-main">Fossil fuel power station</span> 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, oil, 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.

<span class="mw-page-title-main">Fuel economy in automobiles</span> Distance traveled by a vehicle compared to volume of fuel consumed

The fuel economy of an automobile relates to the distance traveled by a vehicle and the amount of fuel consumed. Consumption can be expressed in terms of the volume of fuel to travel a distance, or the distance traveled per unit volume of fuel consumed. Since fuel consumption of vehicles is a significant factor in air pollution, and since the importation of motor fuel can be a large part of a nation's foreign trade, many countries impose requirements for fuel economy.

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.

<span class="mw-page-title-main">Alternative fuel vehicle</span> Vehicle not powered by petrol or diesel

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 and health concerns including climate change and air pollution, 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.

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.

<span class="mw-page-title-main">Greenhouse gas emissions by the United States</span> Climate changing gases from the North American country

The United States produced 5.2 billion metric tons of carbon dioxide equivalent greenhouse gas (GHG) emissions in 2020, the second largest in the world after greenhouse gas emissions by China and among the countries with the highest greenhouse gas emissions per person. In 2019 China is estimated to have emitted 27% of world GHG, followed by the United States with 11%, then India with 6.6%. In total the United States has emitted a quarter of world GHG, more than any other country. Annual emissions are over 15 tons per person and, amongst the top eight emitters, is the highest country by greenhouse gas emissions per person.

<span class="mw-page-title-main">Hydrogen train</span> Train transporting or using hydrogen

In transportation, the original (2003) generic term "hydrail" includes hydrogen trains, zero-emission multiple units, or ZEMUs — generic terms describing 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, as the hydrogen fuel cell train. Widespread use of hydrogen for fueling rail transportation is a basic element of the proposed hydrogen economy. The term has been used by research scholars and technicians around the world.

<span class="mw-page-title-main">Hydrogen internal combustion engine vehicle</span> Vehicle with hydrogen internal combustion engine

A hydrogen internal combustion engine vehicle (HICEV) is a type of hydrogen vehicle using an internal combustion engine. Hydrogen internal combustion engine vehicles are different from hydrogen fuel cell vehicles. Instead, the hydrogen internal combustion engine is simply a modified version of the traditional gasoline-powered internal combustion engine. The absence of carbon means that no CO2 is produced, which eliminates the main greenhouse gas emission of a conventional petroleum engine.

<span class="mw-page-title-main">Landfill gas utilization</span> Method of producing electricity

Landfill gas utilization is a process of gathering, processing, and treating the methane or another gas emitted from decomposing garbage to produce electricity, heat, fuels, and various chemical compounds. After fossil fuel and agriculture, landfill gas is the third largest human generated source of methane. Compared to CO2, methane is 25 times more potent as a greenhouse gas. It is important not only to control its emission but, where conditions allow, use it to generate energy, thus offsetting the contribution of two major sources of greenhouse gases towards climate change.

<span class="mw-page-title-main">FV-E991 series</span> Japanese fuel cell electric multiple unit train

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.