It’s scummy, it gunks up your favorite ponds, but it just might be a pretty good way to make biofuels.  Yup, I’m talking about algae, that green, slimy autotrophic, photosynthetic plant.  It might be hard to think about algae as something useful, considering whenever humans interact with the stuff, it’s usually to get rid of it.  Corn we can at least see being helpful.  But algae?



So let’s take a look at how this works.  While algae is hanging out on water surfaces, it takes in carbon dioxide and sunlight from the atmosphere and converts them to oxygen and biomass.  Algae does this in an extremely efficient fashion and then the biomass can be converted into all kinds of biofuels: ethanol, biodiesel, jet fuel, biomethane, whatever. Of course, this CO2 the algae captured is later released into the atmosphere when the fuel burns, but at least algae doesn’t produce new CO2.

Some more good news about algae fuel:

Those little algae buggers can live on all kinds of water surfaces, including near wastewater treatment plants (and as a bonus, putting algae farms there drastically reduces their fertilizer requirements).

After algae farmers have taken out as much energy-rich biofuels as they can, the leftover biomass can be fed back to new algae as a nutrient source.

The US Department of Energy estimated that if the algae fuel replaced all other fuels in the US, it would take up about 15,000 square miles of space.  That’s about 1/7 of the US area planted in corn.

Map of US corn

That's a loooot of corn...

And an added bonus: algae fuel is a second generation biofuel, which means it’s not made out of a food crop.  See, that’s a big pitfall of first generation biofuels like corn-based ethanol: you can only make so much before the food supply is threatened and food prices increase.

However, it’s still unclear if researchers will able to make this technology more cost effective.  The Pentagon is claiming it’s just months away from making algae jet fuel for $3 a gallon.  But then again, we’ve been working on this technology for over 30 years and we just haven’t yet seen big payoffs.

That seems to be a trend with biofuels.  And that’s why this whole thing is so tricky.  We can’t just stick a pipe in the ground and get an answer for everything, like we did with oil.  There are many budding solutions to the energy crisis, no clear front-runner, and limited resources to put into developing new technology.