We tend to think, old technology is quickly becoming outdated and its place is in museums and history books. However, some of seemingly old-fashioned technology may make a comeback. Scientists from the University of Alberta are currently looking for ways how to improve efficiency transit train operators and it looks like the most suitable way is to bring back the flywheel technology.
Light Rail Transit in Edmonton city is an important mean of public transportation and it is searching for improvements. According to scientists flywheel technology could be a very easy yet effective way to save some money. They say that flywheels would bring the energy consumption down by 31% and cost by 10%. Furthermore, because flywheel is just a metal disc, which spins using electricity and can transform rotational energy back to electricity, it is very simple to make. It can be improved by using vacuum and magnetic bearings to make the flywheel levitate to reduce friction too.
Scientists call flywheels mechanical batteries. They are used in some racing cars, International Space Station, electric systems of big cities. When trains stop or accelerate, they make lots of energy, which is usually transformed into heat and wasted. However, electric cars are already using regenerative breaking, so trains should be able too. However, electric vehicles use batteries for this purpose, which is not that suitable for trains.
Pierre Mertiny, one of the authors of the research, said: “It’s difficult to use a conventional battery for this purpose. You need to recharge and discharge a lot of energy very quickly. Batteries don’t last long under those conditions”. Flywheel would take this energy when train is stopping, transform it into mechanical energy by spinning, and then back to electric when train starts moving.
Hanover in Germany is already conducting such tests in its train systems. Here flywheels are stored in stations, which eliminates the need to install them directly into the trains. This means that technology can be implemented in a relatively simple way and because it is already being tested other cities will be able to take advantage of the results of these tests.
They say that flywheel technology is old and is pushed out by batteries. However, sometimes it is good to look into the past to search for inspiration for new solutions to the problems of our times.