Thursday, May 08, 2008

Energy Crunch: Algae May be the Answer

On a recent edition of Australia's Science Show, they looked at how researchers are working on a cost-effective way to squeeze hydrogen out of algae. In massive quantities, this process can power entire cities.

Here's how it works.

Typically when plants convert sunlight into energy, they release oxygen. Basically, they use the sun's radiation to split water (H2O or hydrogen dioxide) into its elemental pieces hydrogen and oxygen. Normally, plants combines the hydrogen with CO2 (a greenhouse gas) to create the energy they need to survive.

Now, if you deplete algae of sulfur, they modify this process so instead of combining hydrogen with CO2, they combine oxygen with CO2 to get the energy they need. In that case, Hydrogen is the byproduct.

This is a win-win since the algae pulls CO2 out of the atmosphere and it also creates a renewable energy source.

Algae can be cultivated in "square box-type bio-reactors" anyplace they fit (for example, on non-arable land so it doesn’t interfere with the food supply). These bio-reactors are big, up to a square kilometer each. And it would take 33 of them to power the city of Queensland (population 4.2 million) for a year.

Here's the problem.

Currently the conversion efficiency of the algae-hydrogen process is just 1 percent (in other words, one percent of the sun's energy gets converted into hydrogen). If this is going to be a commercially viable process, the efficiency level needs to reach 7 percent.

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I started pound360 to channel my obsession with vitamins, running and the five senses. Eventually, I got bored focusing on all that stuff, so I came back from a one month hiatus in May of 2007 (one year after launching Pound360) and broadened my mumblings here to include all science.