The biofuel farm contained only a small wind turbine, solar panel and container of green scum packed within a tub-size frame floating on the water. But its design could someday spawn fleets of robotic farms that harness the ocean winds and sunshine to make cheap, algae-based biodiesel fuel for cars, trains and aircraft.
That vision set forth by BEAR Oceanics aims for self-sustaining robot farms capable of steering clear of boats or ships as they rely solely upon wind and solar power to grow algae year-round. The robotic farms would turn algae sludge into 5 gallons of biofuel per day with a sped-up version of the geological process that created Earth's fossil fuels — all without the risks of drilling for oil or fracking for natural gas.
"At this point, you've turned biomass into a biofuel, and you haven't used any chemicals, so that you don't have a toxic waste stream," said Rudy Behrens, an engineer at BEAR Oceanics. "We can do this on a large scale without disrupting the food chain or creating a hazard."
A human-scale project
The first test system sank under the furious assault of a male swan caught up in the heat of mating season rivalries. Undiscouraged, Behrens and BEAR Oceanics have already built and tested a bigger, swan-proof system that resembles a pyramid-shaped greenhouse.
Now the Pennsylvania-based startup is looking for help from online do-gooders to build its first full-size robot farm. It recently posted a project on the crowd-funding website Kickstarter to ask for $2,000 in donations.
"I meant this to be a human-scale technology that people could do either as a part-time effort, or as a small business or as a major business," Behrens told InnovationNewsDaily. "It's meant to be economically viable at a very small scale, but you can scale it up as much as you like."
Building a robotic farm would take an estimated $1,200 and 140 man hours. Such robots could end up churning out biodiesel for between 30 to 60 cents per gallon, Behrens said.
Turning sludge into fuel
The biodiesel relies upon a sludgy mixture of six organisms, including the blue-green spirulina algae and Azolla water fern. Such a mixture has proved capable of not only doubling its mass every 92 minutes inside a lab at Rutgers University, but also growing in the harsher environment of a Pennsylvania greenhouse from late summer through winter and spring.
"The whole basis of this system is that you use indigenous biomass, so you don't have the problems of invasive species in the environment," Behrens explained. "You certainly don't have the problems of using bioengineered organisms."
Then it's time for harvest. A mild electric current bursts the algae cells to release lipid oils that will eventually turn into biodiesel. The robotic farm ends up with something like hydrogenated vegetable oil floating on the surface, even as the remaining sludge gets recycled into growing more algae.
To sidestep typical biodiesel production involving toxic chemicals, BEAR Oceanics turned to thermal depolymerization — a method that uses heat and pressure to turn the "vegetable oil" into proper biodiesel. Pumping the oil through a tiny opening creates tiny bubbles capable of reaching 1,400 degrees Fahrenheit and pressures of 5,000 pounds per square inch.
Turning robot dreams into reality
But all that biofuel won't do anyone any good if the robotic farms end up wandering lost at sea. BEAR Oceanics built a robotic control system that can detect movement around itself and calculate a path to avoid any other vessels.
It can even automatically head for a "safe zone" and drop anchor if an electronic glitch occurs — a safety feature that got the approval of the U.S. Coast Guard. Now all that Behrens and BEAR Oceanics can do is wait and see whether the online crowds at Kickstarter show similar approval by donating.
"I just read about Kickstarter, and it seemed consistent with how I wanted this to be human-scale technology," Behrens said.