Excess Wind Power Turned Into Gas in Denmark Using Hydrogenics Technology

[Jim Lane]

2. This is really a storage technology, not a new energy source.

One big advantage of fossil fuels over wind and solar is that a fossil-fuel power plant can generate power whenever it's needed. Wind and solar generate power when the wind is blowing or the sun is shining, but not otherwise. Critical to giving renewables a larger role in our energy supply is being able to store the energy when it's produced and then deliver it when it's needed.

This technology starts off with "excess wind power" to generate hydrogen. Presumably, when the wind is blowing on a nice day when people don't need much heating, cooling, or artificial lighting, the plant would run the unneeded electricity through water to separate it into hydrogen and oxygen. The hydrogen can be combined with carbon from atmospheric carbon dioxide to form methane, which can be burned to generate energy. The burning would release carbon dioxide, completing the carbon cycle. (Although an early step uses carbon dioxide, this is not a sequestration method, because the same amount of carbon dioxide re-emerges at the end.)

Most storage methods like this lose some of the energy en route. I wish the linked article had given an estimate of how efficient this would be (i.e., how much of the energy that you put in do you get back out).