Solar Bio-Oil Extraction: Biomass Energy: Eco20/20

Solar Bio-Oil Extraction

Algae bio-fuels are already one of the most refreshing options for reducing the use of fossil fuels. Now, scientists in India are proposing that solar powered extraction could become a part of the process, making the global algae bio-fuels industry an even greener concept.

Why Chose Algae Bio-fuels?

* Algae doesn't need freshwater or farm land, it can grow in toxic water. Algae is used by waste treatment plants to assimilate nitrates and phosphates. In fact, when bio-diesel algae farms are sited near manufacturing plants that produce carbon dioxide the farms can help decrease the levels of local pollution, because the algae 'fuel' consumes some of the carbon dioxide and releases oxygen while it grows. Algal bio-fuel also releases less carbon dioxide than gas or heating oils when it is consumed.

* It's also not unreasonable to expect algal oil production to be more than a hundred times better per hectare of land than bio-oil production from soybeans or corn.

How Oil is Currently Extracted From Algae:

* Currently, extracting oils from a biomass requires the use of an oil press, a hexane solvent extraction, or a super-critical-fluids method wherein algal biomass is pressurized and heated, then CO2 is mixed with the algae to stimulate it to turn into oil. The super-critical-fluids process currently produces the best results, but also requires the most expensive equipment, so it costs the most overall.

The Solar Bio-fuel Option:

* Scientists at the Indian Institute of Science, in Bangalore, are exploring the idea of using solar panels for extracting oil from algae as an improvement in bio-fuel production. The scientists have proposed that genetic manipulation could make the algae secrete more oil, naturally; and using solar panels for heat could boost that oil production further, because studies have found that bad environmental conditions, like nutrient starvation or extreme temperatures, can cause an algae biomass to produce a higher lipid with oil content.

o The team has proposed the genetic modification of thermophilic diatoms which are already known to secrete more lipids with oil content when exposed to a heated environment. The team would use solar panels not for generating electricity but for slowly heating the diatoms. After spreading the genetically-modified algae on solar panels, they plan to collect the secreted lipid by maintaining a thin layer of water on the diatoms so the secreted oil droplets can separate and rise to the top of the panels, which could be tilted so the oil could be removed.

o Karthick Balasubramanian, one of the researchers at IISc, says, "The choice of optimal species for oil production needs a study of different species of diatoms and their response to varying environment conditions…for achieving the best possible results."

Green technology growing even greener sounds like a truly spectacular idea.