Finding new methods of processing wastewater is very important. Using a combination of wastewater and algae to produce biodiesel is even better, because it’s “doubly green”, as the algae neutralize water pathogens as they feed and eat out carbon dioxide to produce fuel.

The main advantage, the Rochester Institute of Technology researchers say, is that algae are easier to grow than corn and doesn’t consume precious resources such as freshwater or land to grow. On the contrary, those plants grow and do photosynthesis in the most harsh environments, where nobody really wants to grow anything else.

“Algae—as a renewable feedstock—grow a lot quicker than crops of corn or soybeans,” researcher Eric Lannan said in a statement. “We can start a new batch of algae about every seven days. It’s a more continuous source that could offset 50 percent of our total gas use for equipment that uses diesel.”

The scientists isolated and extracted the lipids from Scenedesmus, a single-celled alga which they grew in a treatment plant in Irondequoit, NY.

“Algae will take out all the ammonia [and] 88 percent of the nitrate and 99 percent of the phosphate from the wastewater — all those nutrients you worry about dumping into the receiving water,” Lodge said in a statement. “In three to five days, pathogens are gone. We’ve got data to show that the coliform counts are dramatically reduced below the level that’s allowed to go out into Lake Ontario.”

The first lab tests have been made using only 30 gallons of water. A tank that they used at Environmental Energy Technology used 100 gallons, and the plans are to use as much as 1,000 gallons to produce fats that Northern Biodiesel will process into fully-usable biodiesel.