Turn off that light!

By Phil Plait | March 28, 2009 5:17 pm

Hey, tonight is Earth Hour! I almost forgot!

At 8:30 local time tonight, turn off your lights for an hour. Not all of them, just the ones you aren’t using. Shut down the appliances, too. Don’t leave the TV on, don’t set up the automatic coffeepot for tomorrow (leaving ground beans in a coffeemaker for that long oxidizes them and makes them bitter anyway), whatever. You know your place better than I do, so poke around and find things to unplug.

It also helps to turn off outside lights, too. Take this chance to go outside if you can and look at some stars! Saturn is up now at sunset, hanging under Leo’s belly. Orion is up, too, and Sirius, the brightest star in the night sky. Maybe you’ll see the newly upgraded space station!

I think this is a good idea. It’s not a big deal, and won’t save the world… but it might make you aware of the stuff you leave on all the time. Now, if I can just get my teenaged daughter to shut off lights ever… and you kids GET OFF MY LAWN!


Comments (47)

  1. Kirk

    while I guess it could have a good intention (though I think that’s arguable), the whole earth hour thing doesn’t do much except make people in the first world more aware of how to lower their electricity bills. the same amount of energy is being produced by power plants, it’s just going to waste because everyone who lives comfortably enough has the luxury of choosing whether they want to appreciate and make use of the energy or not. we should be spending our time working to help people who aren’t fortunate enough to live in developed countries with access to reliable energy yet, not turning off appliances to lower our own bills. although I have to agree seeing the stars better is a very attractive idea

  2. Kevin

    In less than 20 minutes I plan on going dark for the hour. Unfortunately I can’t take your advice about stargazing Phil, because it’s cloudy here. :(

  3. Now If I only had the Galileosope I ordered for the kids… 😉 Can you really see the space station from Earth? I don’t think that’ll be happening for us in LA even during Earth Hour…

  4. Ender

    Just the lights you aren’t using? Oh my all you people who do that tonight are being sooooooo like environmentally responsible.

    I always turn off lights I’m not using because I don’t want a huge electricity bill. I pay even more attention to the kettle and tumbler-drier because they use months’ worth of light bulb power.

    Sense of perspective people…

  5. Miko

    Yes, be sure to turn off the lights you aren’t using. But wait until 8:30 to do it, and don’t forget to turn them back on an hour later, even if you still aren’t using them.

  6. Cameron

    Should I go attach a flashlight to the photocell on the highly-inefficient streetlight outside?

  7. AndrewC

    Huzzah for meaningless gestures! Oooh look at me I turned out a light, I care, I’m part of the solution *Gives dismissive wank gesture*

    Now thats cynicism!

    Seriously though this does less than nothing regarding climate change, except make people feel good/smug. The prevailing (mis)conception people have about fighting climate change is that the policies will force society back to the stone age. Encouraging everyone to turn everything off-even if it’s just for an hour and meant only to be symbolic- only adds fuel on that fire.

  8. kvenlander

    AndrewC, I disagree. Turning off your lights for an hour globally sends a message to ourselves that we’re all in this together. So it’s symbolic, but we’re a symbol-manipulating species. Nothing will ever get done unless we can get regular people thinking about these issues and building pressure in their political systems. And even then it’s going to be hard. But we can’t afford cynicism either.

  9. It doesn’t solve any problem but for some it will be an awareness raising event. The idea the businesses and city governments can shut off some lights without all hell breaking loose is great. It could lead to real energy savings and (in my dreams) darker skies.

  10. Chris A.

    Good FSM, what a bunch of cynical wet blankets! (Except kvenlander–good on you.) Fer crying out loud, people, it’s meant as a gesture to get people thinking (and talking, and…?) about global climate change. Take it for what it is, a symbol of unity against something that threatens us all. Lighten (darken?) the hell up! Didn’t your mothers teach you “if you don’t have anything nice to say, don’t say anything at all?” Sheesh!

  11. From what I’ve seen, the number of paper/cardboard posters, and the environmental damage done to make and dispose of them outstrips any benefit that is gained during Earth Hour.

    The illusion of doing something worthwhile is much worse than doing nothing because it impedes real progress – people can feel good about making a difference without actually making a difference.

    I don’t support Earth Hour mostly for those two reasons. Kirk captures the third really well in the first post.

  12. KC

    >while I guess it could have a good intention (though I think that’s arguable)

    Oh really – can you show us any proof that Earth Hour has bad intentions?

    As Chris mentioned its just a gesture – and even if you don’t believe in climate change/global warming, surely we can agree that we waste too much energy. And even if most of our electricity is generated domestically – overall we are too dependent on foreign energy sources.
    Don’t be jerk about it if you don’t want to participate.

  13. Paul M

    Every year I wonder if all those candles have a bigger carbon footprint than the lights they replace.

  14. Mechman

    What a great end to earth hour….at exactly 9:30 I was watching the ISS pass almost overhead, as it drifted silently by. It was one of those times that it actually was quiet in the back yard too…no cars, no sounds at all….just me and the ISS….very peaceful!!

  15. Anyone who is serious about this should try something a bit more ambitious. How about taking a cold shower every day for a week? That’ll save more energy, and it’ll certainly make you think. Ah, but that actually requires sacrifice rather than mere symbolism.

  16. To all of the snickerers: No, it’s not going to change the world. It’s not going to directly affect your carbon footprint’s size. It’s not going to fix the hole in the ozone layer, refreeze melted glaciers, or replenish our fresh water supply. What it will do:

    – Make people aware of the little things they take for granted
    – Teach kids to care about the little things they take for granted
    – Give us all an hour when we might (given the weather) be able to see just a few more stars
    – Get us all off of our computers, away from the video games, and out from in front of the TV for an hour

    My 3rd grader’s teacher has made a big deal out of it and he is now very interested in light pollution. It made him think.

    If it were something that cost us to do – something that maybe used more energy or contributed to the problem like so many other initiatives do, I could understand the cynicism, but it doesn’t. It’s FUN.

  17. Ted

    Awareness is a good thing. I would if we should take this to the next level – such as if cities instead of individuals decided to implement this (kidding) :)

  18. Togusa

    All the lights and electrical stuff at my place went dark at 8:30pm EDT on the dot. I even unplugged a couple of night lights for good measure. My only illumination: two battery-powered “flameless candles” (my apartment lease forbids open flames, so real candles are a no-no).

  19. MadScientist

    The police told me I wasn’t allowed to take out the street lights with my carbine – what killjoys.

    But seriously, except for getting a glimpse of a few stars through the haze of pollution, what does this accomplish? I’m not into feel-good non-remedies. While the neighbors were switching off their lights I was busy processing data with my large and loud computer to try to earn a crust.

  20. DLC

    oooh, I know! let’s have Earth Minute!
    Don’t breath for a minute, reduce your Carbon Footprint!

  21. Autumn

    If nothing else, a few folks will not turn everything they turned off back on. Perhaps a few will even realise that turning the floodlights off makes things a bit more beautiful, and they don’t flick ’em on tomorrow.
    And the power plants operate at the lowest level they can given the demand (and a little extra in case of a sudden extra demand) to save costs, so a whole city or two shutting off their lights probably does have an impact on the operation of the local plant, if only for a few hours.

  22. Chris R

    I had forgotten all about this. Thankfully, the planet decided to enforce the hour itself, as my power was knocked out by storms.

  23. Stephen

    Do people really leave lights on they’re not using, except by accident? I find that bizarre. Likewise, I can’t believe people leave outside lights on when they aren’t outside! Do people have money to burn or are they just idiots?

    Is this a US thing?

  24. MadScientist


    I hate to spoil your party, but power plants do not instantaneously adjust to demand. They typically operate close to their rated capacity under all conditions; perhaps ramped up a bit more at some times of year. Some grid switching may go on to balance the power distribution but that’s about it; the boilers will produce pretty much the same power output, but less of that power will be used. Earth Hour is really just a social thing, but I worry that people will develop all the wrong ideas. I never bought into the argument that “everyone knows it’s making no effect, it’s just sending out a message of unity”; in my experience far too many people believe that it is actually making a difference like all those neighbors who were harassing me about not turning off all my lights and my computer – they don’t see me as a wet blanket, they see me as the evil dude who doesn’t care about the environment. The arguments over my not putting pizza boxes into the recyclables container doesn’t help me either.

  25. Even I almost forgot that it was the Earth Hour. I live in Kolkata (previously known as Calcutta), India. I turned off all the lights for an hour.

    I did urge some of my friends to do so. But I don’t know if they’ve cared to turn off the lights. In reply to those who think that it’s useless, I’d like to say that you should do this not to save the earth, but to show that you care. But, of course, everyone has a difference of opinion.

    But I regret to say that none of my neighbors took part. I was, perhaps, the only one in our residential complex to do it.

    In fact, I’ve planned not to limit this activity to a particular day. I will try to do it as much as possible in my daily life and request others to do so through my blog.

    I will write something about this soon on my blog.

    Right now, I’m too excited about 100HoA.

  26. bad Jim

    The point is to let everyone know that we have to change our ways, that our way of life is not sustainable. We don’t have to buy a bigger car each year, a bigger TV, a bigger house. We’re dying younger than our European brethren because our waistlines are getting bigger, too. There’s only so much we can do immediately to switch to alternative energy sources; in the short term we’re going to have to become more efficient.

    Horror of horrors, we may have to give up some things our parents and grandparents didn’t have, just for the sake of our children and grandchildren.

  27. flawedprefect

    To all you naysayers – yes, it is mainly symbolic, but a couple of years ago, it was just Sydney doing it (I love my home town). This year, it was about 4000 locations worldwide. It is a simple show of who really cares about energy consumption and usage. In Sydney alone, the figures are about a 9% drop in electricity usage – we switched off the lights of the Harbour Bridge and Opera House for an hour. Folks went out to pick a good vantage point to see the lights switch off, when just three months ago, they picked the same vantage points to watch fireworks go off these Aussie icons.

    Whether it makes a small difference or a big difference, the point is clear: more people care about what we consume, and all it takes to show this care is as simple as switching off a light for an hour.

    Our candle-lit dinner was bloody RIPPA!

  28. A wholly pointless excersise in which I did not engage, and you should be ashamed for promoting it.

    There is little value in turning off or unplugging unused devices, especially when they consume as little power as a common incandescent lightbulb. There is no value at all in turning them off for one hour a year, especially when we continue to waste energy on pointless illuminations, calculations, and excersises. The energy spent bothering about it is probably at least as significant as the insignificant amount of energy saved.

    If you’re really concerned about energy conservation, don’t turn off your lights. Check your insulation. Then join me in the movement to abolish Daylight Savings Time.

  29. Angel

    Pleeeeaaaase, Phil, you are a science based mind. You have a strong science knowledge. You should have a high knowledge about planetary climate.

    Of course, every try to diminish the carbon or petroleum usage is useful, not only because of the contamination.

    But, please, use your skeptic side and do some analysis of the real problem.

    Yes, World is heating. Simply, we don’t know how much and we don’t know the real consequences.

  30. Wow. I never thought I’d see so many people loosing their s*** over other people turning their lights off. Not just angry, either…but WAAAAY angry. Wow.

    Perspective: Ur doin it wrong!

    I’m part of a local astronomy organization whose primary mandates is light pollution abatement. I should think that just about every reader of this blog should care at least about that. Then again, people like to get angry lots.

    I took some pretty pictures instead.

  31. I’ll say it again, just so it’s clear.

    Earth Hour creates, for the vast majority of the people who participate, the illusion that they are being pro-active for the environment.

    The illusion of doing a good deed is worse, in my opinion, than deliberately not doing a good deed because the illusion lets you think you’ve achieved something when at best you’ve done nothing, and in the case of Earth Hour, you can make a reasoned argument that all the paper wasted to promote it makes things WORSE.

    It’s not like people suddenly have an epiphany and after EH sit in the dark, never to use their electrics again.

    And let’s say electricity use drops 20% worldwide for that hour. That’s 1/5 of 1/24 of 1/365 of a year’s energy use: 0.23% of the annual electricity (not even total energy) budget saved… and I’m fairly confident that worldwide electricity use doesn’t drop anywhere near that.

    From that saving, deduct the cost of mowing down thousands of trees to print those ubiquitous, high-quality posterboard EH announcement posters; to print all the laser-printed notices that EH sycophants stuck on every flat surface for the last month; the environmental cost of all the chemicals to make the paper; the environmental and energy cost of collecting them all and hauling them to the landfill or recycling depot… I’m not convinced EH even comes out ahead of the game.

  32. The value of Earth Hour to me (and to many others who aren’t suspicious cynics who come across sounding “holier than thou” about how EH doesn’t help anything) was to stop what I was doing, shut down the computers, lights, etc.; light a few candles and have a nice conversation with my husband for an hour. We’re busy people — that hour was a gift to ourselves. It’s a symbol — pure and simple. And if it got people to thinking about simplifying and not having everything ON all the time, then it serves its purpose. So, snigger all you want, you ravening cynics who “know” this can’t work. Sometimes a cigar is just a cigar.

    Had it been clear here last night, we would have been out stargazing.

  33. Hoonser

    Not a big fan of earth hour. I already keep the lights off for 16 hours a day in my home. I don’t own a car, and I walk and take public transit everywhere. However, that doesn’t qualify as environmentalism because it’s practical and lacks the jumped up self satisfaction *real* environmentalism carries. Real environmentalism requires you to give yourself a big pat on the bag for doing absolutely useless gestures that make you feel good.

  34. JMM

    Turned on every inside and outside light in the house and opened the blinds. Even if it is wasted money, it is my money and choice to do so. Not that of some local, state, or federal agency. Global warming and al related nonesense are nothing more than attempt to wrestle economic and polictal control. Light pollution is a sepate issue. Lived in the country and it was very nice to star gaze. Lived in a brightly lit city, and it was nice to be able to easily see at night. Moved to new Jesey with low urban lighting and it is hard to see and feels dangerous. Had a choice at each step, no need to have it imposed on anyone.

  35. actuator

    I was with JMM. I highly recommend the 2008 “Best Scientific Blog” winner wattsupwiththat.com by Anthony Watts. CO2 is not a pollutant. It is necessary for life on earth and it has gone up and down for millenia. It is highly arrogant for politicians to use CO2 as a basis for expending billions that will ultimately achieve nothing but a reduced standard of living for most of mankind. I am all for reducing real pollutants and we must stop fouling our nest, but CO2 is not on the list.

  36. actuator: arguing from authority (quoting wattsup as an award winner) is a bad idea. Those awards are popularity contests, and nothing more. It doesn’t mean that site has any good science on it at all.

  37. MadScientist Says: “power plants do not instantaneously adjust to demand. They typically operate close to their rated capacity under all conditions; perhaps ramped up a bit more at some times of year.”

    This description is true for baseload power plants, the ones run at full capacity all the time (like hydro, nuclear and large steam turbines). To handle the daily/hourly changes in demand they use what are called “swing generators,” which are typically gas turbines that can be adjusted quickly. During EH, or other lower demand periods, they can be ramped down or even taken completely off line.

    The newest trend in grid management is the so-called “smart grid” which can redirect power almost instantaneously. This is an outgrowth, nay a necessity, with the “green” generation technologies like wind and solar, whose output is far from reliable.

    As far as carbon footprints go, I’m still waiting for the peer reviewed studies that show the causual link between the 2% of the global CO2 load caused by humans and climate change. I’m also waiting for the definitive study showing the cause of past warming periods and why that’s not the case this time. Carbon is a political scapegoat because it’s easy to identify and easy for people to understand, but being a lagging indicator, it doesn’t seem to be a cause but rather an effect of climate change.

    – Jack

  38. Angel

    I agree with Jack Hagerty. But, in fact, even with those almost instantaneously adjustments to demand, a quick disconnection of a significant part of demand can lead to an accidental power down of some power plants, wich can get a chain reaction of power-downs.
    (please, forgive me if I use wrong words. Ask in spanish 😉 )

    Anyway, in Spain, the decrement in power consumption during EH was about 2%, wich is not enough to give any problems.

  39. Robert Carnegie

    First, I forgot. Next, I thought it was just lights. Don’t hassle us. Not the refrigerator, not the dialysis machine. (Of course if you open the refrigerator door… close your eyes.)

    Raybe you’d like to calculate the money saved on the electric bill. Depending on how many lights you leave on usually, you could buy yourself a candy bar. Or just a candy.

    It is an awareness exercise. Afterwards you can carry on switching off lights not in use and it only means that you can afford to buy more candy.

    As for the effect of CO2 emission on climate and sea level, I live up on a hill but maybe I should buy rubber boots. New York, I don’t think I’ll miss, but how will Spider-Man manage?

  40. Joe Meils

    Wouldn’t it be easier to just flip the main breaker for an hour? My wife doesn’t want me to do it, but her iron lung tends to really drive up the light bill, so….

  41. actuator

    I merely recommended wattsup as a source of information. Some of it is very good science and some of it is highly questionable. However, although there is more anti AGW than pro, you will find both sides being argued. My main point was that CO2 is not a pollutant and we really need to focus efforts (and therefore government actions) on real environmentally toxic issues. It seems to me that Mr. Gore et al are more interested in self agrandizement and political influence than they are in “good science”.

  42. 8:30 PM to 9:30 PM local time, at this time of year, is a pretty lousy hour for stargazing whether your lights are on or not. Since we’re on Daylight Savings Time (unless you live in Arizona or certain parts of Indiana), this hour corresponds to a wan 7:30-8:30 PM standard time — the twilight glow hasn’t even faded from the horizon yet! It doesn’t get super-dark until at least 10 PM around here.

  43. hey…mother nature needs a break, anyway mostly all of you guys are arrogant people, just go with the flow and do it u cant cause n e more harm! so just do it!


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