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Artificial Leaf Could Provide Cheap Energy

Posted by Soulskill on from the make-like-a-tree-and-catalyze-the-electrolysis-of-water dept.

sciencehabit was one of several readers to tip news of a sunlight-harvesting artificial leaf, writing: "Nearly all the energy we use on this planet starts out as sunlight that plants use to knit chemical bonds. Now, for the first time, researchers at the Massachusetts Institute of Technology have created a potentially cheap, practical artificial leaf that does much the same thing—providing a vast source of energy that's easy to tap. The new device is a silicon wafer about the shape and size of a playing card coated on either side with two different catalysts. The silicon absorbs sunlight and passes that energy to the catalysts to split water into molecules of hydrogen and oxygen. Hydrogen is a fuel that can be either burned or used in a fuel cell to create electricity, reforming water in either case. This means that in theory, anyone with access to water can use it to create a cheap, clean, and available source of fuel."

2 of 326 comments (clear)

  1. Re:So it's a solar cell.... by rubycodez · · Score: 4, Interesting

    Normal solar panels have albedo of 0.35, which is close to average of earth 0.30. We'd be far better off thermally using that than burning fossil fuel or fissioning atoms. However, comparing the energy input of the sun to what man generates, the fraction is so very tiny that the global direct thermal effects (not greenhouse gases which is another discussion) of our power generation in essentially zero.

  2. Re:So it's a solar cell.... by joocemann · · Score: 4, Interesting

    You should consider:
    1) The energy harvested by solar would hit the earth anyway, and thanks to laws of thermodynamics, we can't get 'more' from it than would already arrive.
    2) The energy harvested using fossil fuels hit earth millions of years ago and was stored in chemical bonds that we break with combustion. If we otherwise did not choose to release this energy via combustion, it would stay in chemical form.

    There is a difference. There is also no excess blanket of CO2 being produced, where carbon that has been absent from the atmosphere for millions of years is now reintroduced, and as it is a heat storing gas, it aides in global warming.

    There is a difference.