Comments by "eDoc2020" (@eDoc2020) on "Rotary Valves Make Normal Valves Look Silly - Why Aren't We Using Them?" video.

I think the electric motor is the future for main propulsion. Combustion engines will likely remain as range extension generators. AFAIK if you always run at one RPM and one torque many of the difficulties are eliminated.
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@argh100100 What do you mean electricity can't be efficiently transported? I would assume you meant it can't be stored easily but your next sentence was about storage.
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@lanzer22 Hydrogen cars have their own problems which IMO means they will never reach mass market appeal. Have you seen Jason from Engineering Explained's video on the subject? Some highlights: low energy density and the need for advanced containment vessels. Hydrogen combustion engines have the low inefficiency of any other ICE combined with hydrogen-specific issues. Hydrogen fuel cells are more efficient but require rare precious metals and IIRC have a limited lifespan. And then there's the production aspect: commercial hydrogen is usually produced from fossil fuels using steam reforming and green hydrogen comes from electrolysis which is low efficiency.
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@argh100100 A 98% efficient system has twice the losses as a 99% efficient one but who cares? I know electricity transport isn't quite that efficient but AFAIK it's still at least 80% in almost all cases. Very long or underwater AC lines have lighter losses but there's a relatively easy solution: high voltage DC. Switching lines from HVAC to HVDC eliminates all the capacitive losses.
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@argh100100 20% loss, that's the same as the 80% efficiency I suggested. Still not bad. IIRC hydrogen fuel cells have a lower efficiency and that's before you consider transportation losses, let alone generation losses.
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@argh100100 If you have a diesel generator that can generate cheaper electricity than the grid you've found something amazing.
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