For the complexity of efficiency conversion of prototype and model hydraulic turbines many calculation formula are put forward but there is not universal formula.

由于原型与模型水轮机效率换算的复杂性，尽管已提出许多计算式，但至今仍未有一个被一致确认的统一公式。

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The problem has been that high temperatures are necessary to power heat-based conversion systems, yet solar cell efficiency rapidly decreases at higher temperatures.

问题是热能转化系统需要更高的温度，而太阳能电池的效率在高温下迅速降低。

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A little over a decade ago, the best photovoltaic efficiency, or sunlight conversion into electricity, was 10 percent, and now it can reach 40 percent.

大约十年前，光电效率(即光能转换成电能的转换率)只有10%，而现在已经能达到40%。

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This high efficiency PV technology allows Suntech to achieve conversion efficiency rates in the range of 18% to 19% on PV cells manufactured with monocrystalline silicon wafers and 16.5% to 17.5% on PV cells manufactured with multicrystalline silicon wafers.

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SunPower boasts the highest efficiency among all players in the solar industry and has developed a Gen 3 cell technology, which has a conversion efficiency greater than 23%.

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As far as climate benefits, supposedly it generates electricity at 50-55% conversion efficiency.

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