A new heat engine with no moving parts is as efficient as a steam turbine

Re:A new heat engine with no moving parts is as efficient as... by HPsquared on Thursday April 14, 2022 @06:06AM (#31024969)

Heat supplied at high temperature is more valuable than heat supplied at low temperature. Look up Carnot efficiency, and "Exergy". There are limits on how efficient a heat engine can be, defined by the "hot" and "cold" temperatures. A hotter "hot" side allows higher efficiency.

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Re:A new heat engine with no moving parts is as efficient as... by sdenton4 on Thursday April 14, 2022 @10:22AM (#31027426)

That sounds like room for innovation, rather than an unfair trick. If you can find ways to achieve high temperature cheaply and easily, you get better efficiency.

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Re:A new heat engine with no moving parts is as efficient as... by hinkley on Friday April 15, 2022 @01:15AM (#31036797)

I think the point they're making is that 40% efficiency is amazing when you have a 1500° difference between the hot and cold side. But at 2000° the theoretical efficiency limit is higher, for all heat engines.

It's like if I compared the top speed of your Porsche on a perfectly straight road, clear weather, no wind, to the top speed of my sedan, but I've got it pointed toward a very high cliff and I'm claiming a top speed of 400 mph (straight down). It's not a fair comparison, because I am cheating by exploiting a greater 'height'.

If we actually compared the same thing, yours would still be at least 50mph faster than mine (at a slight angle from straight down)

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