Biofuel is considered to be a promising way to shift our energy needs to sustainable and climate-neutral sources. Replacing petroleum with fuels made from crops or other plants basically recycles CO2. The plants absorb it as they grow and release it when they are burned.
The real issue with biofuels is the choice of feedstock. Plants that are energy-rich and easy to convert to fuel like ethanol are more valuable for feeding people: corn, sugar beets and sugar cane are good examples.
As the world struggles to feed its growing population, it is important to find biomass feedstock that doesn’t take food away from people or utilize prime agricultural land. Thus, biomass like agricultural residues, fast-growing trees and grasses, and aquatic crops such as seaweed and algae are increasingly attractive.
A research group in Norway has recently made a breakthrough in producing bio-oil from kelp. The idea is to mimic the natural processes that produced petroleum, but instead of it occurring on a geologic time scale, it happens in minutes.
The Norwegian process is known as fast hydrothermal liquefaction. A slurry of kelp and water is heated to high temperature at a very rapid rate. The result is a bio-oil yield of 79%, meaning 79% of the kelp is converted into bio-oil.
Like other laboratory discoveries, the Norwegian process for oil from kelp faces the challenge of scaling up. The process is relatively simple and does not require chemical catalysts that are typical of many biofuel techniques. As a result, there is optimism that it may be practical to produce bio-oil from kelp on an industrial scale.
**********
.
Web Links
Turning Humble Seaweed to Biofuel
Photo, posted August 26, 2009, courtesy of NOAA’s National Ocean Service via Flickr.
.
Earth Wise is a production of WAMC Northeast Public Radio.