The excessive use and depletion of fossil fuels has brought in sight that there needs to be a way to reduce the amount of fossil fuels required to produce an amount of energy. The main consumer of fossil fuels are transportation systems which is creating a big concern since the amount of carbon dioxide gas emitted which promotes global warming. Therefore, it is not just a concern but a necessity to reduce the amount of energy generated by fossil fuels.
The Flywheel is incorporated into any vehicle to increase the efficiency and hybridize the vehicle. The Flywheel is used as an secondary energy system in all vehicles including battery electric vehicles. The flywheel energy storage is also combined with mechanical transmissions for brake energy recovery.
Figure 1 – Flywheel energy charge and discharge when braking force is applied
The Energy stored in the flywheel is released to the wheel when there is an immediate acceleration required. This technology can also be used in Light transportation which is for public transport generally short distances. Continuous energy is provided to the train, the train receives higher energy to charge the Flywheel near the Stations and it continuously uses the stored energy when it moves away. The train is slowly charged back to its full capacity when it reaches the next station. The potential energy saving when a flywheel is added to the train is about 29.8%.
Figure 2 – Power flow to and from the Flywheel Energy Storage system.
There are several diesel-electric locomotives, which includes the position and the location of the flywheel in the long distance trains to improve the efficiency and reduce fuel consumption of the locomotive. Comparisons between normal only diesel engines with motors and diesel engines with flywheel technology, this explains that the Hybrid vehicle is always better. New technologies like carbon fiber flywheels further help in increasing the speed of the flywheel for better energy storage. The placement of the Flywheel also matters for trains. The best location to place a flywheel is found out. Continuous Variable transmissions are required for the flywheels to be coupled with the engine. The most important part in a flywheel system is the planetary gearbox.
Figure 3- The working principle of a Flywheel energy storage system in trains.
The efficiency saving of each car, short transit trains and heavy haul trains are found out. The total number of trains and cars currently running in the United States are combined. The total Efficiency of all the vehicles and the energy saved by the vehicle is found out. This gives an idea about the savings in Fuel, and the reduction in carbon dioxide in the air.
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