The most widely used type of engine is combustion engine and although even under the name of combustion engines, you'd find a lot of variations, one thing is more or less always constant; they all adhere to the conventional combustion system in one way or another. The constant among all the variations is the fact that the output is usually some form of rotation; turbine blades, pistons and crankshafts. Toyota is working to change that by introducing a new type that it has named as Free Piston Engine Linear Generator (FPEG). What is so special about FPEG? It has no crankshaft and generates three phase electricity.
FPEG works in a peculiar way; during the power stroke of the cycle, the pistons are driven to push permanent magnets through a coil that is located around the cylinder chamber and that results in the production of electricity. So what is Toyota doing? It is combining two known processes; combustion engines and electromagnetic induction in this new type of engine. The reason why this setup is being given the limelight is because of the fact that as per Toyota, the thermal efficiency of FPEG is 42% and that is quite an improvement when you compare it to the thermal efficiency of the conventional combustion engine; 25-30%.
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