The key to thermal efficiency for internal combustion engines is compression ratio.

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If a company can expand its output to meet the market demands simply by internal efficiency improvements (which is what productivity means to some extent), why should they go out and hire more labor?

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The case for starting from within starts to look even better when you consider the fact that many of the companies that have made internal efficiency improvements in order to achieve emissions reduction are not only improving their corporate image, but are also saving money.

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"We really and truly expect that fuel cells are going to double the fuel efficiency of the best internal combustion engines and in some cases triple it, " Roan said.

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Technologies such as internal combustion engines and gas turbines will continue to improve gradually in efficiency but they are familiar and developed.

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Staff are now rewarded for efficiency in using leather (the costliest input) and run an internal market to sell offcuts.

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