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Re:Belgians drilling a hole in the ocean?? by mrvan · 2013-01-18 01:02 · Score: 3, Interesting · on Belgium Plans Artificial Island To Store Wind Power

"We" made a similar island for storing contaminated sludge in a part of the IJsselmeer. This reservoir island is 1km across (so slightly smaller but same order of magnitude) and 45m deep.

Some links: google maps, Dutch wiki, google translated Dutch wiki.

According to this page, this island cost around 250 million to build. At 1 km across and 45m deep, it can hold around 35E6 sq meters of water=3.5E10 kgs of water. No idea whether it works that way, but the potential energy might be m*g*h=3.5E10 * 9.81 * 22 (avg.) ~ 7E12 joules, or the output of a 3500MW power plant for 7E12/3.5E9 2000 seconds or about half an hour, assuming 100% efficiency and no fuckups in my orders of magnitude.

I'm assuming it is easier to build this in the ocean than to dig it in a shallow lake (the lake around the reservoir is about 2.5m deep), because otherwise why not just dig it in the shallow lake? Since the north sea is about 50m deep offshore from the low countries, a reservoir of 3km accross wil hold 9 times as much energy, or around 5 hours of output from one plant. Whether that is enough or not I have no idea. I would suppose that the cost could be around 9*250 million = 2.5 billion euro, which is cheaper than building a new plant but nothing to sneeze at.

Re:Wind Could NOT Provide 100% of World Energy Nee by Anonymous Coward · 2009-06-22 16:58 · Score: 0 · on Wind Could Provide 100% of World Energy Needs

Well, this isn't quite true. Averaged over larger regions--such as a state or a country--there is wind all the time. Naturally, the larger the region, the more consistent the power will generally be for that region. There are several studies considering different regions and different technologies (i.e., current power infrastructure, or proposed HVDC lines). Below are some notable findings.

From Stanford (pdf): interconnected wind farms could provide 33-47% of baseload power in Colorado, Kansas, New Mexico, and Oklahoma.

In Europe, 20% of baseload could be from wind power with the current infrastructure (pdf), or 70% from wind (and 100% renewables) with a high voltage DC transmission network (pdf).

Other more local findings are 25% baseload in Minnesota, and 50% in the UK. The point, then, is that wind can provide much more power to the grid than previously thought, and is often reasonably economical.

There is no tabula rasa by jfengel · 2005-06-06 03:55 · Score: 1 · on Effort to Create Virtual Brain Begins

Newborns have considerable content. For example, they have a predisposition to learn language, and not just any language, but human languages. Human languages are far from random things; they have particular structures, like words and sentences. Language doesn't have to be that way, but every human language is. There are many other language universals.

There are a lot of other things that appear to be built-in to the human brain (some aspects of gender roles, love for family, a sense of fair play, the ability to see in 3D). A newborn is a lot more than a mass of unwired neurons.

These things are far from completely understood, but the notion of a blank slate has been pretty well debunked.

Re:Interesting Statistic by realSpiderman · 2003-12-18 05:11 · Score: 3, Insightful · on Global Dimming

I think this is a complete myth.

How else do you think, the following produciton plant is possible. Even if it only gets 10-20% of the energy from the solar panels on the building, it still produces far, far more panels than are installed on the building.

Solarfabrik

And also see this study.
The energetic amortization for a solar powerplant is 6-7 years!!! And this is a pessimistic study, others even say it is only 3 years.

mirrors by dotgod · 2002-07-23 05:35 · Score: 3, Informative · on Mandrake Linux 9.0 Beta 1

Australia

ftp://ftp.planetmirror.com/pub/Mandrake/8.2/i586/ (Brisbane)
Austria

ftp://ftp.univie.ac.at/systems/linux/Mandrake/8.2/ i586/ (Vienna)

ftp://gd.tuwien.ac.at/pub/linux/Mandrake/8.2/i586/ (Vienna)
Belgium

ftp://ftp.belnet.be/packages/mandrake/8.2/i586/
Costa Rica

ftp://ftp.ucr.ac.cr/pub/Unix/linux/mandrake/Mandra ke/8.2/i586/
Czech Republic

ftp://ftp.cesnet.cz/OS/Linux/Mandrake/mandrake/8.2 /i586/ (Brno)

ftp://ftp.fi.muni.cz/pub/linux/mandrake/8.2/i586/ (Brno)

ftp://klobouk.fsv.cvut.cz/pub/linux-mandrake/Mandr ake/8.2/i586/ (Prague)

ftp://mandrake.redbox.cz/Mandrake/8.2/i586/

ftp://sunsite.mff.cuni.cz/OS/Linux/Dist/Mandrake/m andrake/8.2/i586/ (Prague)