From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,873e3ac877e7b6b6 X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2003-08-16 07:26:59 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed.icl.net!newsfeed.fjserv.net!kibo.news.demon.net!demon!newshub1.home.nl!home.nl!skynet.be!skynet.be!louie!tlk!not-for-mail Sender: lbrenta@lbrenta Newsgroups: comp.lang.ada Subject: Re: Nuclear Reactors & Blackout References: <3F3E3B4D.5893@mail.ru> From: Ludovic Brenta Date: 16 Aug 2003 16:26:46 +0200 Message-ID: User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.2 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Organization: -= Belgacom Usenet Service =- NNTP-Posting-Host: 217.136.15.32 X-Trace: 1061044019 reader1.news.skynet.be 302 217.136.15.32:40740 X-Complaints-To: usenet-abuse@skynet.be Xref: archiver1.google.com comp.lang.ada:41580 Date: 2003-08-16T16:26:46+02:00 List-Id: According to the press here in Europe, it is perfectly possible that a similar blackout, of similar magnitude, occur here. The cause is not related to software (i.e. a blackout could occur even with 100% perfect software). A blackout would be the result of a number of factors. 1) Electricity cannot be stored (d'oh!) and therefore, there are dispatchers that are on watch 24 hours a day to match supply and demand. These dispatchers are usually country-wide. Their job is to ensure that the production of power is exactly balanced by the consumption, and that all electricity produced is properly carried over the grid. 2) The high-voltage lines in the grid have limited capacity; they overheat if too many ampers go through them (d'oh!). There are "fuses" that protect these lines against overheating. 3) All power stations in Europe are interconnected; they are all on the same high-voltage grid. This is done so that if one power station fails for one reason or another, other power stations can supply more power to make up for it. One third of Europe's power is from nuclear plants, but that's irrelevant. Thus, if there is a big surge in demand for electricity, some lines in the grid will shut themselves off in order not to melt down (I mean the *lines*, not the *power plants*). The other lines in the grid will then have to carry the extra power. They, in turn, run an increased risk of exceeding their nominal capacity, and may also shut themselves down. It would appear that the blackouts in the US were caused by such a surge in demand (hint: air conditioning devices throughout the US account for 30% of all electric power consumption). This was combined with the fact that the demand in electric power has increased by 30% in the last 10 years. And this was further combined with the fact that very little investment has been made, over the last 10 years, to increase either the supply capacity of power plants, or the bandwidth of the grid. Basically, it's like a giant fuse went off because of too much demand on the whole system. I've heard that one power plant went off-line, and that that started the whole process of quickly overloading the lines from all other power plants. Given the situation, I don't think that this is very important. I think other blackouts could, indeed *will* happen, whether or not a power plant goes offline in the future. It may very well happen that one day there is just too much demand and too little supply. This has happened before in California, albeit to a lesser scale. -- Ludovic Brenta.