How the Electric Motor Compares?
How does the electric motor compare with the internal combustion engine?
The modern internal combustion engine clearly works well as far as power under the hood.
It must nevertheless have appeared at one time as an impractical impossibility. Intrinsically it remains an ear splitting (unless muffled) 'heater' thus of very low efficiency (measured as fuel in versus power out). It shall melt down unless hooked up to a serious cooling system. But thanks to generations of brilliant and dedicated engineers, mechanics, assemblers, manufacturers et al the 'gas engine' is found everywhere today—albeit producing around 25% efficiency—while the electric motor is around 3(!) times as efficient.
Even with the muffler some of us find the combustion engine's noise at least annoying. The electric motor is whisper quiet without needing a muffler. While the exhaust manifold of the combustion engine can reach temperatures of 1800 degrees F. even after a hard ride an electric motor is barely warm to the touch of the hand and without needing a cooling system.
The combustion engine reaches its max torque by revving to a few thousand r.p.m. The electric motor provides 'instant' torque. Here expressed in an ad for the Chevy Volt electric car: "Without a traditional transmission, 273 lb.-ft. of low end torque has nowhere to go except to the tires and pavement. This helps explain why a vehicle with an electric propulsion system can feel so powerful and exhilarating."
Almost all combustion engines in use, past and current, are fueled by fossil fuel and spew out green house gases and other pollutants. The electric motor emits no exhaust at its non existing tail pipe while the power generating facility does depending on its source of power. Our Seattle City Light, while regrettably not representative for the nation, generates about 94(!) % of its power from renewable sources.
Modern combustion engines are admirably reliable. Still a mere 4-cylinder, single overhead cam, 2 valve engine has at least 27 moving parts: 1 cam, 8 rockers, 8 valves, 4 pistons, 4 rods, 1 crankshaft plus 1 timing chain plus pumps and flywheel. The electric motor has one(!) moving part, the rotor, and requires no lubrication.