Why Are Locomotives Diesel Electric?

Dieselelectric technology was first utilized in switchers (or shunters) locomotives in the 1920s, which were used to move trains around in railroad yards and assemble and disassemble them. The American Locomotive Company was one of the first companies to offer “Oil-Electric” locomotives (ALCO). In 1931, the ALCO HH series of dieselelectric switchers went into production. The system was modified in the 1930s to accommodate streamliners, the fastest trains of the day. Dieselelectric powerplants were popular because they substantially simplified the transmission of motive power to the wheels, as well as being more efficient and requiring less maintenance. When a locomotive has four or more axles, direct-drive transmissions can become quite complicated. A direct-drive diesel locomotive would also necessitate an excessive number of gears to keep the engine within its powerband; connecting the diesel to a generator solves this problem. In a direct drive system, a torque converter or fluid coupling can be used to replace the gearbox. Hydraulic transmissions are said to be more efficient than diesel-electric transmissions.

Are electric motors used in diesel locomotives?

Diesel locomotives and trains use diesel fuel to operate. If you believe that, you are somewhat correct. To deliver power to the wheels, modern diesel trains use traction motors, which are electric motors. The traction motors are powered by the diesel power plant, which does not turn the wheels.

Why are diesel locomotives more powerful than electric locomotives?

A locomotive that is powered by electricity from overhead lines, a third rail, or on-board energy storage such as a battery or a supercapacitor is known as an electric locomotive.

Because the electric generator/motor combination solely functions as a power transmission system, locomotives with on-board fueled prime movers, such as diesel engines or gas turbines, are classified as diesel-electric or gas turbine-electric locomotives rather than electric locomotives.

Electric locomotives benefit from electric motors’ high efficiency, which is often above 90%. (not including the inefficiency of generating the electricity). Regenerative braking, which allows kinetic energy to be recovered during braking and used to put power back on the line, can improve efficiency. Regenerative braking is available on newer electric locomotives thanks to AC motor-inverter driving systems. Because there is no engine or exhaust noise and less mechanical noise, electric locomotives are quieter than diesel locomotives. Because electric locomotives do not have reciprocating parts, they are easier to operate on the track and require less maintenance. Because the capacity of the power plant is significantly greater than the capacity of any one locomotive, electric locomotives can deliver higher power outputs than diesel locomotives, as well as higher short-term surge power for rapid acceleration. Electric locomotives are suited for frequent-stop commuter rail service. Electric locomotives are employed on freight routes with a significant volume of traffic or in locations with well-developed rail networks. Even if they utilize fossil fuels, power plants are significantly cleaner than transportable sources like locomotive engines. Geothermal power, hydroelectric power, biomass, solar power, nuclear power, and wind turbines are all examples of low-carbon or renewable energy sources. Electric locomotives are typically 20% less expensive than diesel locomotives, with maintenance expenses of 25-35 percent cheaper and operating costs of up to 50% lower.

The expensive expense of infrastructure, such as overhead lines or third rail, substations, and control systems, is the main downside of electrification. Electrification is hampered in the United States by government policy, which imposes higher property taxes on privately held train systems that are electrified. The EPA regulates locomotive and marine engine exhaust emissions in the same way that automobile and truck emissions are regulated, in order to restrict the quantity of carbon monoxide, unburned hydrocarbons, nitric oxides, and soot produced by these mobile power sources. Because train infrastructure in the United States is privately held, railroads are hesitant to engage in electrification. Railway networks, like roads, motorways, and rivers, are considered part of the national transportation infrastructure in Europe and worldwide, and are frequently subsidized by the government. Rolling stock operators are charged fees based on how much rail is used. This enables the significant investments required for technically and economically advantageous electrification in the long run.

What is the difference between a diesel locomotive and a locomotive that is powered by electricity?

The electric locomotive, as its name implies, runs on electricity. The diesel locomotive is powered by diesel. The electric train’s engine requires electricity from overhead lines. The diesel train’s engine does not require any direct power or energy from overhead lines to operate.

Trains use electric motors for a reason.

Each traction motor (C) is connected to a pair of driving wheels directly. Using electricity as the locomotive’s “transmission” is significantly more reliable than relying on a mechanical transmission and clutch. Starting a big train from a stop would quickly burn out the clutch.

Why aren’t the train engines turned off?

Because trains are so enormous and heavy, they require the highest possible brake line pressure to stop safely. Loco pilots never compromise on brake line pressure for obvious reasons. Another reason to keep diesel train engines running is the engine itself.

Is it possible to run diesel trains on electrified lines?

Electro-diesel locomotives are used to provide continuous journeys along routes that are only partially electrified without changing locomotives, to avoid extensive diesel running beneath the wires (using a diesel locomotive where electrified lines are available), and to provide a solution where diesel engines are prohibited.

They may be constructed or modified primarily for electric usage, primarily for diesel use, or to function well in either mode.

A electro-diesel (bi-mode) multiple unit train is named electro-diesel multiple unit (EDMU) or bi-mode multiple unit train, in addition to the electric multiple unit (EMU) and diesel multiple unit (DMU), where no discrete locomotive is present (BMU).

Why do we no longer utilize steam engines?

Steam engines, like electric motors, deliver maximum torque and acceleration quickly due to their design, and clean-burning steam power would be hugely advantageous for urban driving where there is a lot of stopping and starting.

To resist the heat and pressure required to power the vehicle in the 1920s, steam cars required massive and hefty boilers, implying that even the smallest steam cars weighed a few tonnes at the very least. Steam-powered cars, on the other hand, might be as light as their normal counterparts thanks to sophisticated materials.

It may be possible to design an efficient, light, and viable steam automobile with a warm-up period of seconds rather than minutes using sophisticated condensers and modern flash boilers. It begs the question: why does no one create a steam-powered car these days, given modern concerns about fuel efficiency and sustainable energy?

Many people believe that steam requires large boilers and engines to work, or that steam cars are bombs waiting to happen because of the tremendous pressure required to operate them. The majority of these, on the other hand, are either completely false or have been disproved by modern technology, electronics, and metallurgy.

A British team established a new steam-powered land speed record of 148mph in 2009, and there have been a few attempts to bring steam power up to date for the modern world. Cyclone Power Technologies, based in Florida, claims to have invented a steam engine that is twice as efficient as an internal combustion engine, although it is still years away from being used in a commercial vehicle.

Commercial manufacturers have mostly ignored steam power, focusing instead on improving existing combustion engine technology and developing new electric and hybrid vehicles. A Volkswagen spin-off business claimed to have created a functional steam engine for a brief period in the 1990s, but that was the closest a major manufacturer has come to steam power, and little has been heard since.

Steam power today has to compete with more than just traditional combustion engines, thanks to the growing popularity of electric and hybrid vehicles. While hybrid/electric automobiles are a step in the right direction, they will continue to rely largely on fossil fuels until renewable energy becomes widely available.

Hybrids, in example, combine a tiny petrol (or occasionally diesel) combustion engine with an electric motor; they consume less gasoline than a conventional combustion-powered car, but they still require it. Electric automobiles, as we’ve already mentioned, tend to just move carbon emissions from the exhaust to the power plant, despite the fact that they produce fewer emissions.

As the Cyclone team points out, emissions are far less of a worry for steam engines, albeit they are far from gone. Nonetheless, the company’s website claims that their steam engine burns longer than most, incinerates more hazardous particles, and hence emits fewer exhaust emissions.

Although the amount of pollution produced depends on the type of fuel used, sustainably-sourced fuels may have a lower environmental impact than conventional fossil fuels, which almost invariably burn filthy.

What is the purpose of using DC current in trains?

Trains employ DC motors because of their great torque and precise speed control. DC motors can provide a great blend of powerful starting torque and adjustable speed for seamless but precise performance in industry applications when compared to AC motors. Trains are a large-scale application, therefore a DC motor can transport the heavy load ahead effectively and safely.

Train windscreen wipers, a tough application that must be able to cope in a variety of situations, are another great application for DC motors. Depending on the conditions, a decent windscreen wiper motor should be able to work well at any speed. This necessitates accurate speed control, allowing them to adjust to changing conditions smoothly and easily.

Which is more powerful, a diesel or an electric train engine?

Diesel-hydraulic locomotives are inefficient compared to dieselelectric locomotives. The first-generation BR diesel hydraulics were much less efficient (about 65%) than diesel electrics (around 80%). Additionally, early versions were found to be technically more sophisticated and more likely to break down in many nations. Germany was the first country to develop hydraulic transmission for locomotives. The relative virtues of hydraulic vs. electrical transmission systems are still debated: hydraulic systems are said to have lower weight, more reliability, and lower capital costs.

Are there gears on diesel trains?

The locomotives are meant to tow passenger-train cars at speeds of up to 125 miles per hour and weigh between 100 and 200 tons (91,000 and 181,000 kg) (200 kph). Siemens’ latest engines can generate up to 4,200 horsepower, which can be converted into about 4,700 amps of electrical current by the generator. The drive motors generate roughly 60,000 lb-ft of torque using this electricity. A secondary diesel engine and generator give electrical power to the remainder of the train. The head-end power unit is a generator that produces between 500 and 700 kilowatts (kW) of electrical power.

The locomotive is classified as a hybrid vehicle because of its diesel engine and electric generators and motors. We’ll start by understanding why locomotives are made this way and why they have steel wheels in this post. The layout and major components will be discussed after that.