The proton exchange membrane fuel cell (PEMFC) is one of the most promising power sources for future electric vehicles due to it's high power density and energy conversion efficient.

质子交换膜燃料电池（PEMFC）具有较高的功率密度和能量转化效率，最有可能成为电动汽车的动力源。

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These transitions occur frequently but only require a one-time conversion cost and thereafter can be obtained in the efficient form.

这些转化是很频繁的，然而其转化代价却是一次性的，之后就可以以有效形式获取。

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OCTETS as a string unit specification does not require any conversion and is more efficient.

OCTETS作为一种字符串单元指定不需要任何转换，而且使用起来更加有效。

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The good news: There are a growing number of very competent companies manufacturing solar cells for efficient conversion of this sunlight to electricity.

FORBES: Suvi Sharma

Panasonic's artificial photosysnthesis system has a simple structure with highly efficient CO2 conversion, which can utilize direct sunlight or focused light.

ENGADGET: Panasonic Photosynthesis System converts carbon dioxide to organic material with plant-like efficiency

Back on July 27th, I wrote about how surprised I was to find shares of Power-One (PWER), a provider of renewable energy and energy-efficient power conversion and power management solutions such as photovoltaic inverters used in solar power applications, trade down after reporting blow-out second quarter results.

FORBES: Explain This One, Part 2