CAN NASA FLY ALGAE & WASTEWATER?

NASA bags algae, wastewater in bid for aviation fuel
Katie Howell, May 12, 2009 (E&E Publishing via NY Times)

SUMMARY
The National Aeronautics and Space Administration is developing an algae fuel by growing the algae in wastewater. The Ames Research Center program hopes to (1) generate a high quality liquid fuel, (2) create an inexpensive method of treating sewage and (3) systematize an effective way eliminate carbon dioxide.

The researchers bag sewage, add algae and float the semipermeable plastic containers in the ocean. The plastic, originally developed for recycling astronauts’ wastewater during space missions, allows the algae-cleansed freshwater out but keeps the saltwater from coming in. NASA calls the bag an Offshore Membrane Enclosure for Growing Algae (OMEGA).

One proposal would install the OMEGAs with offshore wind. (click to enlarge)

The algae eat the sewage for its "nutrients" and transmute water, sun and CO2 into algal lipids (fatty oils) that can be refined into anything petroleum can. The byproducts are oxygen, released into the air, and clean water, released into the ocean.

The bags are designed to last 3 years and then be recycled as plastic mulch. Should they leak, the ocean’s saltwater would kill the algae and the waste would dissipate in the ocean’s vastness.

The NASA project would move this installation offshore. (click to enlarge)

COMMENTARY
The expense of growing the algae and then harvesting and refining the algal oils make the undertaking too expensive as a pure fuel source. But adding the benefits of wastewater processing and CO2 sequestration could make the venture economic.

At present costs, the OMEGA process is cost competitive with land-based algae operations because it does not entail the expense of tracts of land for pond farms or bioreactor facilities. Going forward, the high price of precious water resources required in small quantities by land-based systems would also give the OMEGA system an economic advantage.

The challenges: (1) Finding plastic capable of withstanding pounding waves and cold temperatures without becoming too brittle to remain semipermeable and allow osmosis. (2) Finding venture capital to fund the research.

And it considers wastewater to be nutrients! (click to enlarge)

A California Energy Commission grant will help pay for a demonstration project scheduled to go into operation within a year. Good results and an improving economy could bring more support.

Jonathan Trent, the project's lead researcher, foresees his OMEGAs producing fuel enough – 21 billion gallons/year – to meet U.S. aviation needs. He says the OMEGAs would require only a tiny portion of the vast ocean and could be distributed and monitored – or even franchised – by local fisherman.

Trent has also proposed installing OMEGAs in conjunction with offshore wind installations. A potential trial is under consideration for an offshore installation in the Baltic Sea.

Trent’s OMEGAs are only one of many biofuels research projects under NASA’s Green Ames research umbrella.

Trent would put these plastic bags out at sea, fill them with nutritious waste and make them semipermeable. (click to enlarge)

QUOTES
- Jonathan Trent, project lead researcher, NASA/Ames Research Center: "Algae are the best source of biofuels on the planet that we know about…If we can also clean [wastewater] at the same time we create biofuels, that would great."
- Trent: "It's energy-free…It doesn't cost us anything. Osmosis works by itself."
- Trent, on what would happen if a bag should leak: "Freshwater algae can't compete in the marine environment…We're not putting something out there that could become an invasive species…[and] the only thing we're putting in the water is already in the ocean anyway."

Algae biofuels are still several years away at best. (click to enlarge)

- Trent, on the economics: "We don't think this would be cost-effective if we just go after the fuels…But we're functioning on at least three different levels: making the products -- fuel, fertilizers -- then wastewater processing and carbon sequestration. The economic model becomes more reasonable."
- Trent, on the problem of water: "We've solved the problem of evaporation, weeds, structure…And we think we've added other benefits like processing sewage and sequestering carbon."
- Trent, on the value of the proejct: "On a planet with a population growing at exponential rates and resources dwindling, we're almost in a state of emergency on a timeline measured in decades…I think it's important, this process of coming up with alternatives. ... I don't know if OMEGA is the solution, but it's something that should be carefully scrutinize.