I wrote:
> Eventually, after cold fusion is established, there will be market niches > that demand somewhat more efficient mechanical conversion, such as > aerospace engines and other mobile applications. This will probably not be > needed for automobiles, ships or railroad locomotives. Conventional > automobiles have only 20% efficient engines, this can probably be achieved > with conventional steam turbine or Stirling engines. > With cold fusion, what you want is a high power to weight ratio. A 5% efficient engine producing 10 kW per kilogram of engine is much better than 20% efficiency with 1 kW per kilogram. That seems odd from our present perspective. With a liquid fuel chemical engine, the fuel itself weighs a great deal. A 5% efficient engine would have to carry 4 times more fuel than the 20% engine. For a long range vehicle such as a ship, the fuel would outweigh the engine. With cold fusion, no matter what the efficiency is, the fuel weighs nothing. The only problem with an inefficient cold fusion engine is that you have to have a large radiator. When you get down to around 3% you end up with something like a 19th century steam tractor, which is all engine: http://de.geoview.info/19th_century_umrath_steam_engine_still_up_and_running_at_the_2010_langenpfunzen_tractor_fair,38612696p Here is a useful textbook, partly available on line: "The Economic Growth Engine: How Energy and Work Drive Material Prosperity" https://books.google.com/books?id=nLfJKVK9uJsC&printsec=frontcover&source=gbs_atb#v=onepage&q&f=false See the discussion starting on page 101. - Jed
