Demand of hydrogen has grown continuously in recent years as it is an important industry resource and a clean fuel.

氢气既是重要的工业原料又是清洁的燃料，近年来需求量剧增。

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Energy firms often call gas a clean fuel: burning it releases roughly half as much carbon dioxide into the atmosphere as burning coal does.

能源公司常常把天然气称作纯净的燃料：燃烧天然气进入大气层的二氧化碳量大致上是煤炭的一半。

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An artificial leaf would use a reaction that forms part of the natural process of photosynthesis to turn sunlight and water into a clean fuel source.

“人造叶”将利用构成光合作用中部分自然过程的反应作用，将阳光和水变成一种清洁燃料的来源。

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Until that time, consider this a comforting reassurance that a clean fuel era is well within reach.

ENGADGET

They note that President Barack Obama supports natural gas as a clean fuel that has lowered energy bills.

FORBES: Binghamton NY

Now common sense would be for all to look for a Clean Fuel Source like Wind, Hydro, Geothermal and Solar.

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