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0 pointsbshipp7y ago0 comments

Indeed. Take a look at cars, for example. My little 2.0L engine makes more power than a 1970's V8 behemoth could have dreamt of, while simultaneously getting fantastic fuel mileage with minimal pollutants (in comparison).

It's by no means perfect, but by any objective measure it's providing me with more value at a lower energy cost. Energy cost to operate, energy cost to build, energy cost to maintain. And that trend is most certainly not going to reverse any time soon.

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fallingfrog7y ago· 2 in thread

There is a physical limit to the efficiency of a heat engine though. If your powertrain is 25% efficient, you can double it to 50%. But if it's 50%, you cannot double it to 100% unless the engine is operating at a temperature of absolute zero. You're going to reach a point- and current model cars are probably just about there- where the engine is operating about as efficiently as the laws of physics permit, and then you're not going to make further progress. Just google "Carnot cycle" and you can learn more.

cinquemb7y ago

>- and current model cars are probably just about there-

Very true, in order to get more progress, one would have to develop systems that are sufficiently different and more efficient at some level which may be odds with how we currently allocate resources.

AstralStorm7y ago

Such as series hybrids and electric cars. (Dropping complex transmission for batteries, but using a more efficient engine.)

At some point though friction against road and minimum weight for safety and comfort come into play, and once you optimize these you end up with a train. :)

It's the same problem electronics face right now, when they really butt into quantum physics and consequently have huge yield issues - and you can scale horizontally (more transistors) only for subset of problems.

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