Electricity from Seaweed
by Celine Ruben-Salama, New York, NY
on 02.26.07
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!
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But, does it power itself as well?
Nice article. I think, moreover, that the process actually absorbs atmospheric carbon dioxyde, thus killing two birds with one stone. Could that be? Don't ask me how I heard about that, though. I might have misunderstood what I read.
Keep the good work.
All the best
In most of the world, seaweed is still an important fertilizer. Shorefront property used to be valuable for the "mossing rights" and the shellfish, not for recreational purposes.
In Japan, using it for energy may be a good idea for now, but in the long run it really is far more valuable than an equivalent ton of wood or grass.
Seemingly good content, but there is an error in the picture and 1st paragraph. Nori, the green stuff wrapped around that hand-roll and frequently used in japanese cuisine, is in fact pressed algae NOT sea weed.
A molecule of CH^4 has one molecule of carbon in it. When oxidized (burned), it releases to carbon as CO^2, and the hydrogen as water (H^2O) So unless there is some disposal of the carbon dioxide waste product, it will be carbon neutral (to the extent anything can).