Japanese "Eco Rigs"  

Unlike the first comment, this one isn't spam.

I would harldy consider this idea to be a 'green' move. Surely the proliferation of floating pontoons around an entire country the sze of Japan comes with its own seriuos environmental consequences. . . .

Well - green is a relative term - every large scale human activity has some environmental consequences.

The Japanese are in a situation where their population seems to exceed the carrying capacity of their land.

Given that, this potential (albeit far fetched) solution to meeting some of their food and energy needs isn't a bad path for them to follow in a world where resource extraction limits are starting to be encountered.

Great blog!

You're listed as the "blog of note" today on blogger.

Much of the science in the quoted article is terrible:
* Watt hours, so over the whole life of the massive array it'll generate one hour of that wattage? Thats pretty terrible, most single square meter solar panels can achieve that if they last long enough. Get the units right
* Solar cels running LED's, so their just going to change the colour of the light? I'm not sure about the efficiency of such a proposal, and either way thats a lot of hardware to do what the sun does fairly well on its own.

I'm Japanese from Japan living in the U.S. I know how limited their natural energy /resources can be. I think Japan is trying all they can to ease the problems that they have. I hope this will work for them or at least help them to find another way to create energy.. They did it with Kyoto Protocol; I hope Japan will lead other countries to be more aware how serious global warming is.... Gret blog!

I think it's something worth looking into. I mean, we don't know if we don't try. What I like about this idea is that it takes its purpose whilst attempting to giving back to the natural world. The question is however, will that work? Will the gains truly enhance the means?

It's "impressive" that 120 million people live on the ~20% of the land that is not mountainous and forested... but they have long relied on the sea for supplementing their food supply - and feed lots in Oz ;-)

Gav, is there a fundamental reason that you know of as to why we don't hear more geothermal efforts from Nihon (or am I deaf)? The place is littered with onsens (natural hot springs)

rpd - I think you'll find "terrible" science in most newspaper articles that cover technical subjects - and the Telegraph isn't a great example of journalism at the best of times.

In this case I'm assuming that the LED based lighting for aquaculture is for (1) winter, and (2) night time - enhancing yields by increasing the growing "season". LED based hydroponic set ups are pretty common.

SP - strangely enough I've never heard of geothermal power in Japan.

According to this dated document (1999) there were about a dozen plants generating 500 odd MW.

http://www.geothermie.de/iganews/no39/geothermal_energy_development.htm

Apparently difficulty in finding sites (that aren't in national parks or urban areas) and government restrictions on drilling are obstacles to expanding the sector.

SP - a fresh story on geothermal in Japan:

Matter - Japanese Hotsprings Resort Protests Geothermal Power

The earliest geothermal developments did not reinject fluids back for reuse. Initially only 10% was returned to the earth. As a result, in Wairaki in New Zealand for instance -- the second geothermal development in the world -- with only a tenth being returned, the hot pools have been depleted by geothermal drilling.

Japan could more than double its current geothermal electricity supply if it harnessed all the untapped thermal energy from the country's 1,591 hot spots. This can be done while simultaneously protecting hot springs for resorts when the fluids are reinjected after use.

Currently Japan ranks fifth in the world for geothermal power.

Thanks Gav.

Not that I'm a fan of the energy islands idea... but I can think of another plausible reason for the use of the LEDS... even during daytime.

Light attenuation in a thick growth of algae must (I think a function like I = Io e^-kd) be quite high. In a thick algal bloom, cells can be light limited within centimetres of the surface (because of the cells above).

Also, the article mentioned deep nutrient rich water. You could pump the nutrients up... or "pump" the electrons down. Just a thought.

There is also the issue of wavelengths. Although plants have auxillary pigments, they generally photosynthesise best at particular wavelengths. LEDS could be chosen with this in mind. I'm not convinced it's gunna be a winner.... but I suspect this is what the engineers are thinking about.

Yes - good point.