Electricity from Seaweed
Fresh seaweed, often eaten in Japanese dishes like sushi and miso soup, can be quite delicious. However, seaweed that washes up on the shore rots and begins to smell. Collection and disposal of it has long been a major burden for local governments along the coast of Japan. What if this seaweed dredged from the shore could be put to productive use to produce fuel for generating electricity? Tokyo Gas Co. teamed up with the New Energy and Industrial Technology Development Organization (NEDO) in 2002 to find out.
The goal of this joint venture is to create the first power plant in the world that runs off of seaweed. Preliminary research is about to wrap up in March 2007, at which point the results will be used to consider how the system can be put to larger-scale commercial use. After studying the optimal conditions for fermenting kelp, sea lettuce, and other types of seaweed in a test facility in Yokohama, it has been determined that the system is feasible. Here is how it works: First, large amounts of seaweed are crushed into a sludge-like state. Microorganisms are then used to further break down this semi-liquid material; the process creates methane gas as a byproduct. Finally, the gas is used as fuel for an engine that produces electricity. In tests to date, one ton of seaweed has been processed per day, resulting in the collection of 20 kiloliters of methane gas which generates roughly 10 kilowatt-hours of electricity per hour. At present production levels, this is enough energy to power 20 households.
Local governments and maritime companies that have struggled to dispose of seaweed in the past can be enlisted into this effort, which is expected benefit both local communities and the global environment. This is the kind of innovative public sector/private sector collaborations we like to see. :: Japan Echo
Thanks to Ovadia for the tip!