# Worldwide disaster - how long until the lights go out? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [March 19, 2008, 5:59pm UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964 "2008-03-19T17:59:34Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [March 19, 2008, 5:59pm UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/1 "2008-03-19T17:59:34Z")
Suppose we find ourselves in a science-fiction novel scenario and suffer from some disaster that kills off most of humanity, but doesn’t harm structures (think disease rather than bombing. no ambulatory dead in this scenario, either), how long would we still have electricity? Say 10-15% of able-bodied adults in all occupations survive. Would it be days or just hours before a now largely unmanned system collapsed from lack of day to day maintenance? ---
**Author:** ![Baker](https://avatars.discourse-cdn.com/v4/letter/b/bb73d2/32.png) [@Baker](https://boards.straightdope.com/u/Baker)\ **Post date:** [March 19, 2008, 6:03pm UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/2 "2008-03-19T18:03:49Z")
In the recent show, _After People_, on the History Channel, it was figured most lights go out within a very short period, a couple of days at most. It was posited that the last electric lights to go out would be in the grid powered by Hoover Dam, because the power plant and generators are rigged to go on for a long time without maintenance. So the lights in Las Vegas, some of them anyway, might have a year or two. ---
**Author:** ![micro-dust](https://avatars.discourse-cdn.com/v4/letter/m/9de053/32.png) [@micro-dust](https://boards.straightdope.com/u/micro-dust)\ **Post date:** [March 19, 2008, 6:05pm UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/3 "2008-03-19T18:05:48Z")
I think a few “cities” with disaster plans would survive, like Disney World and Cape Canaveral. ---
**Author:** ![DesertDog](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/desertdog/32/11503_2.png) [@DesertDog](https://boards.straightdope.com/u/DesertDog)\ **Post date:** [March 20, 2008, 4:13am UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/4 "2008-03-20T04:13:49Z")
This was covered last year, but there’s no search now. General answer: If the electric grid is still tied together, a couple of days at the most. The coal plants will quickly run out of fuel without people to push the mounds of coal around, and their coming down will drag the nukes and hydro plants with them. If the individual utilities isolate themselves (a more likely situation in your scenario) the nuclear plants would probably last a couple months before an unintervened hiccup made them trip off. Hydro a lot longer. ---
**Author:** ![Dunderman](https://avatars.discourse-cdn.com/v4/letter/d/ecb155/32.png) [@Dunderman](https://boards.straightdope.com/u/Dunderman)\ **Post date:** [March 20, 2008, 7:04am UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/5 "2008-03-20T07:04:32Z")
[When the zombies take over, how long till the electricity fails?](http://www.straightdope.com/mailbag/mzombiepower.html) ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [March 20, 2008, 8:55am UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/6 "2008-03-20T08:55:34Z")
A 10-15% survival rate means that pretty much all the utilities will survive, but in restricted areas. There’d be 6-9 million people left in the U.K., for instance. And it won’t take that long to replenish the population - less than a century - assuming people wish to do so. ---
**Author:** ![Pushkin](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@Pushkin](https://boards.straightdope.com/u/Pushkin)\ **Post date:** [March 20, 2008, 10:46am UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/7 "2008-03-20T10:46:00Z")
[QUOTE=Quartz] And it won’t take that long to replenish the population - less than a century - assuming people wish to do so. [/QUOTE] Are there enough mineshafts left? ---
**Author:** ![elfkin477](https://avatars.discourse-cdn.com/v4/letter/e/a9a28c/32.png) [@elfkin477](https://boards.straightdope.com/u/elfkin477)\ **Post date:** [March 20, 2008, 8:23pm UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/8 "2008-03-20T20:23:03Z")
[QUOTE=Priceguy] [When the zombies take over, how long till the electricity fails?](http://www.straightdope.com/mailbag/mzombiepower.html) [/QUOTE] Zombies aside, I think this was really what I was hoping for. Now I just need to find out what sort of power plants we use in NH and ME (hydro and “fossil-fuel based.” Maybe coal?). We have the Seabrook nuclear power plant in NH, but I don’t think PSNH makes use of it since most of the power is sold to FPL. I suppose we could, someday, if 85-90% of FPL’s customers died, right? ---
**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\ **Post date:** [March 20, 2008, 8:56pm UTC](https://boards.straightdope.com/t/worldwide-disaster-how-long-until-the-lights-go-out/441964/9 "2008-03-20T20:56:23Z")
[QUOTE=Pushkin] Are there enough mineshafts left? [/QUOTE] There are nuclear power stations. Remember that there will be 6-9 million people left in the U.K., which is about the population at the time of the industrial revolution. More than enough. I wouldn’t be surprised if after only a decade it were seen as a blessing in disguise.