Sea Lettuce as Energy Crop
Monday, October 19, 2009 9:36:50 AM
Sea lettuce is a rapidly growing alga with a potential output that is more than tenfold larger per hectare than crops cultivated on land. It grows in seawater, in coastal areas, but can also be cultivated in artificial basins on land.
The many species of sea lettuce are a popular food in many of the places where they grow, including Scandinavia, Great Britain, Ireland, China, and Japan (where they are known as aosa). They can be eaten raw in salads, or cooked in soups, and are high in protein, soluble dietary fiber, and a variety of vitamins and minerals, especially iron.
Sea lettuce can, among other marine resources, be exploited for the production of bio-ethanol and biogas.
In a Danish research project, that started in april 2008, about 45 ton dry weight pr. ha (1 hectare is 10000 square metres) were grown in a basin, that is 4 times as much as the yield of energy crops grown on land. If the basin is ventilated with CO2, a 50% increase is possible.
A large Danish project on turning macroalgae into energy started in 2008 and is expected to be completed in 2012. In other countries projects on turning microalgae into energy are ongoing.
At Sandia National Laboratories in the US, for instance, researchers are cultivating green algae that holds promise as a new supply of biofuel.