I read that a massive portion of usable energy is wasted and turned to heat instead of being used to turn the crankshaft — would there be like any way of reducing the heat/cooling the engine so you could get 50-70% thermal efficiency?
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We will never hit 100% efficiency since humans aren’t perfect and nothing we make will ever be. There are ICE engines that are being tried out which might once fully developed get higher efficiencies. They have a design for opposing pistons for the compression and power strokes where two pistons squeeze the mixture and moved apart from each other then the resulting motion from the two camshafts are combined via gears. Another where they use a compression cylinder to precompress the mixture before moving into the combustion cylinder to reach higher compression ratios. But honestly don’t know how efficient either will finally end up at.
We will never hit 100% efficiency since humans aren’t perfect and nothing we make will ever be. There are ICE engines that are being tried out which might once fully developed get higher efficiencies. They have a design for opposing pistons for the compression and power strokes where two pistons squeeze the mixture and moved apart from each other then the resulting motion from the two camshafts are combined via gears. Another where they use a compression cylinder to precompress the mixture before moving into the combustion cylinder to reach higher compression ratios. But honestly don’t know how efficient either will finally end up at.
Average is around 35%, Toyota has an engine they claim is at 41%, I believe it is in the Prius. F1 engines can hit over 50% and Nissan claims to have a prototype engine that can hit 50% over a very narrow range.
The biggest issue is that traditional ICE requires you to have an engine that is very flexible over a large range of loads & engine speeds. This is the opposite of what you want when trying to design ICE for max thermal efficiency. The Nissan engine I mentioned is designed to work as a generator in an electric car and will only operate in a very narrow band, which allows them to optimize it for just that.
As a fun little aside, in order for an engine to achieve max thermal efficiency it needs to be at wide open throttle. This seems counterintuitive because we are talking about efficiency, but thermal efficiency is all about extracting the maximum amount of mechanical power from a given amount of fuel, not what we generally think of efficiency, i.e. mpg or l/100km.
Average is around 35%, Toyota has an engine they claim is at 41%, I believe it is in the Prius. F1 engines can hit over 50% and Nissan claims to have a prototype engine that can hit 50% over a very narrow range.
The biggest issue is that traditional ICE requires you to have an engine that is very flexible over a large range of loads & engine speeds. This is the opposite of what you want when trying to design ICE for max thermal efficiency. The Nissan engine I mentioned is designed to work as a generator in an electric car and will only operate in a very narrow band, which allows them to optimize it for just that.
As a fun little aside, in order for an engine to achieve max thermal efficiency it needs to be at wide open throttle. This seems counterintuitive because we are talking about efficiency, but thermal efficiency is all about extracting the maximum amount of mechanical power from a given amount of fuel, not what we generally think of efficiency, i.e. mpg or l/100km.
Why do people say “ICE engines”? The “E” stands for “engine”. It’s like saying “ATM machine”, “chai tea” or “naan bread”.
The chemical reaction of burning gasoline mixed with air produces a fixed amount of thermal energy based on the number of oxygen and gasoline molecules involved in the reaction.
Ice engines don’t actually use all of that heat energy directly, they use a side effect of the chemical reaction, the pressure created by the reaction, to convert potential to kinetic energy.
The chemical reaction of burning gasoline mixed with air produces a fixed amount of thermal energy based on the number of oxygen and gasoline molecules involved in the reaction.
Ice engines don’t actually use all of that heat energy directly, they use a side effect of the chemical reaction, the pressure created by the reaction, to convert potential to kinetic energy.
Why do people say “ICE engines”? The “E” stands for “engine”. It’s like saying “ATM machine”, “chai tea” or “naan bread”.
Important note, *gasoline* engines only get 20-30% efficiency diesel engines are currently pushing high-40 to low-50% thermal efficiency.
In fact, Rudolph Diesel theorized that at about 60% efficiency an external cooling system wouldn’t be needed and the Reisser cycle engine successfully proved that requiring no cooling system.
Diesel engines are far better than their gas counterparts.
Important note, *gasoline* engines only get 20-30% efficiency diesel engines are currently pushing high-40 to low-50% thermal efficiency.
In fact, Rudolph Diesel theorized that at about 60% efficiency an external cooling system wouldn’t be needed and the Reisser cycle engine successfully proved that requiring no cooling system.
Diesel engines are far better than their gas counterparts.
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