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Earth Hour side effects?

  1. Jan 24, 2008 #1
    I stumbled upon this and have some doubts. First let me explain what is Earth Hour

    On 31 March 2007, 2.2 million people and 2100 Sydney businesses turned off their lights for one hour – Earth Hour
    and they are planning another one in 2008
    http://www.earthhour.org/

    I understand the message that they are trying to get out to people, and I do support the idea that we should be more concious about our energy consumption.

    my question is, if a substantial part of the population actually takes part (say 80+%). Will the initial fluctuations cause any grid failures?

    from my limited understanding, some power plants, nuclear for example have to be constantly running at full capacity? Won't the surplus energy generated be wasted?

    And another thing, once the hour is up, the power stations would have to be restarted and it would be like a blackstart (after a power outage) and its more difficult due to all the reactive loads attempting to draw power?

    The professionals at the utility companies should be able to solve these problems cause they are paid for it. But imagine if the utility companies were unaware and thus unprepared for it?!

    note: this are all assumptions based on my crash course on Electric power transmission from Wikipedia :) So feel free to correct me wherever
     
  2. jcsd
  3. Jan 24, 2008 #2

    Astronuc

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    With millions of people distributed around the world, they are on different grids, so there would not seem to be a problem. In countries, the generating stations are distributed on large grids, and the loads are also distributed on the same grid, so a loss of load can be distributed.

    If 80% of a grid dropped load, then a lot of power plants would be shut off, fairly quickly, and they would have to be staggered on the restart. At that scale, grids would probably be restarted as if it were a recovery from a blackout. Nuclear power plants can be shutoff (scrammed) fairly quickly, but one would rather not do that unless necessary.

    Much generation is baseload, particularly nuclear power plants, of which many are among the largest capacity units on a grid. Utilities generally have a mix of baseload (on all the time and at full rated power) and peaking units (particular gas turbines). Peaking units can come on line rapidly in response to a surge in demand, or alternatively can be shut off rapidly if the load drops. The French utility, EdF, has some nuclear units on load-follow and frequency control.

    If one wants to make an impact with conservation, it would make more sense to switch to more efficient lighting, turn off lights when not in a room, and in general minimize use of electrical appliances.
     
  4. Jan 24, 2008 #3

    jim mcnamara

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    Mass power on-off is not a good idea, simply because it puts a burden on the power management system. If the on-off is large enough and if it covers something like the state of New York, it will incite other problems, largely on the grid management level. Lose the grid and big parts of North America can blackout.

    Hydro-Quebec did something like this - power dumping back in the early '90's without telling other NERC members over here in the US. Caused a bunch of weird problems but did not bring down the grid. Everybody went nuts trying to do end of month power accounting. But HQ were dumping maybe 5000 megawatts not the 100000 MW that bump around in New York State.

    You can figure about about 1000 discretionary (non-base) megawatts per million people. So if you turn off most of the discretionary consumption in California all at once for an hour you are talking about a hell of a lot of power with no place to go. That would affect base loads everywhere on the grid. And if everyone in California flipped the on-button within 15 seconds of everyone else, life would be even more interesting.

    This is analagous to queuing every kid in a giant high-rise dorm building to flush his toilet in complete synchrony. It nukes the plumbing on the lower floors.
     
    Last edited: Jan 24, 2008
  5. Jan 24, 2008 #4

    Evo

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    Stuff like this "earth hour" just seems extremely stupid.
     
  6. Jan 24, 2008 #5

    Astronuc

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    Especially if there is no followup or large scale change in behavior. One hour out of 8760/yr does not an impact make.

    I wonder how much energy is spent organizing/promoting this event? How much energy is consumed by the website?
     
  7. Jan 24, 2008 #6

    RonL

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    The mass population could be educated quickly if service meters were designed to put a control on how much current is drawn into a home at any given time.
    As an example my home has three a/c units 3 ton each, each covering a portion of the house, these should never be allowed to all be running at the same time. Along with all other electric appliances plus lighting, the load in early evening is quite high. If my draw allowance was limited, i would very quickly learn what to have on and when.
    By learning what wattage each of the electric devices draw, people would become more aware of how to conserve electricty. This needs to be more than a one hour effort.

    By adding battery storage and inverters, the smaller draw items like lights, TV, Computers, can be carried thru a power outage for maybe a day or two, or at least take a big load off of the peak demand time.

    The big key is for everyone to know the basics of what comes thru the meter.
     
  8. Jan 24, 2008 #7

    Evo

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    You'll be interested in this thread on the subject.

    https://www.physicsforums.com/showthread.php?t=208665
     
  9. Jan 24, 2008 #8

    RonL

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    Thanks Evo
    I did indeed hit a hot spot, and by no means do i want "someone else" controlling when my current is used. Keeping 200 amp service in place, but with computer controlled breakers not everything could be turned on at once.
    Also I think the peak demand can be reduced a little by the use of battery storage, which can take place at much lower demand times.

    With the right rebate programs in place this need not be such a large expense to the home owner, or small business.

    I almost jumped into a battery discussion last month, but my time is not right at the moment. The technology being over 125 years without much change in design is not right, but that might be a long drawn out issue.
     
  10. Jan 24, 2008 #9

    Astronuc

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    One regional utility in NY had reduced rates from 10 pm - 6 am, so when we lived in that territory, we tried to do laundry (washer and dryer) at night, or get up early and cook breakfast. I think there were also lower rates on the weekends, so we also deferred laundry to the weekends.

    I'm not sure if they still do.

    We keep our thermostats down and the house is relatively heavily insulated.

    I keep reminding my kids to turn off lights, but my son has a bad habit of leaving lights on. :grumpy:
     
  11. Jan 25, 2008 #10

    jim mcnamara

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    Those are TOU - time of use rates.

    Astro -
    Did you guys have interruptible rates - the utility company actually turns off power to high demand appliances whenever system load starts to peak. Saves money in demand costs for the utility which they pass on via the rate. This saves BIG bucks for consumers - circa 30%. So an $.09 kWH becomes .06 for example.

    The usual suspects are electric baseboard heating systems and electic hot water heaters, and electric stoves - they are hooked up to a radio-controlled switch.
     
  12. Jan 25, 2008 #11

    Astronuc

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    The rates just changed according to time of day. I never really investigated how it was done since we were renting a condo and then only for 18 months. We never had a service disruption as far as I know, except for the odd power outage.

    At the condo, we did have electric baseboard heating (my first experience with that), and the walls were 'thin' and poorly insulated. The condo was on a NS ridge overlooking a nearby reservoir. The view (and sunsets) was spectacular, but the wind would whip uphill and we could 'feel' the cold! We had an option to buy, the price was outrageous and I was concerned about the construction. Too bad since it was only 20 miles from the office where I used to work.

    The meter on my house has a telecom line into it.
     
  13. Mar 27, 2008 #12
    As a power engineering (and physics) student I can see issues with reducing the load significantly. When the load changes significantly, frequency imbalances can occur (due to either too much or too little power being produced wrt the load) as it takes time for the generators to adjust to the change in load. At zone substations (33kV -> 11kV for Australian voltages) we have instruments that measure the frequency and if it changes too much the whole substation trips (and a multiple suburbs lose power). Frequency imbalances are likely to be detected across the network. In a worst case senario this results in a whole generator being taken off the grid. It is also very difficult to start a generator after such an event, the power generation company will be on the phone to the distribution company asking them to switch on a given amount of load eg. "switch on 50MW load once every ten minutes for the next hour". This is very much guess work for the distribution company and if they stuff up then everything will trip (due to frequency imbalance) and the whole thing starts again. It would be much easier if Earth hour was staggered but I guess we will just have to wait and see (and hope that the effect isn't great enough to mess with our electricity system).
     
  14. Mar 27, 2008 #13
    My kids too. You are right about follow through. It's not about turning the lights off when you need them to be on, but rather about turning them off when you don't need them. And to reduce all the waste in your life. Of course, I mean my life.
     
  15. Mar 28, 2008 #14
    Earth hour's main goal was to get the message out to the world about energy usage...

    It seems like it has made it this far, so it just depends if the cost of energy to stage that Earth hour, created a reaction that created less energy usage in long-term, on that power grid.

    At least enuf to compasate for the energy, time, and money in the step's of creation.

    Other wise it would create loss of money in short term... I hope the number's was on there side on that Earth Hour...
     
  16. Mar 28, 2008 #15

    turbo

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    One problem with this concept of Earth Hour is that if people follow the timing fairly closely, they will create problems when they dump load all at once, and when they re-establish load all at once. This is a recipe for turbine-generator trips, overloads at the end of the hour, and overall, very inefficient power-plant operations on both ends of the hour. Why promote waste and inefficiency just to make a point, instead of promoting conservation and conservative use of energy?
     
  17. Mar 28, 2008 #16

    cristo

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    The only side effect I can notice is that Google has turned black-- it's weird!
     
  18. Mar 28, 2008 #17

    DaveC426913

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    Y'all don't seriously think that the goal of Earth Hour is to make a difference in power consumption do you?

    Surely you recognize that this is an public awareness measure.

    It's not really so much about education either; it's about insipration. The people have to want to make a change before they will make a change. And it's not so much about us; it about our children. They will grow up aware of this issue. This is long-term planning.
     
    Last edited: Mar 28, 2008
  19. Mar 29, 2008 #18

    Gokul43201

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    I don't imagine the point of EH is to actually help by reducing consumption. I expect the point is to raise awareness for conservation issues - it's a global marketing initiative.

    Edit: Oops! Didn't see the second page of posts.
     
  20. Mar 29, 2008 #19

    G01

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    I just noticed that! It's freaky...
     
  21. Mar 29, 2008 #20

    Moonbear

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    Wow, they actually mentioned this thing on the morning news today (not that I stopped to listen to the story)...otherwise I would have thought this was just another of those pointless internet hoax things (let's all jump at the same time and see if we knock the Earth out of it's orbit, or everyone wear red or yellow or some such on a particular day to show you support X). Maybe it still is and has just sucked in the gullible news reporters. Seems pretty pointless to me.

    Besides, if people follow this, it'll screw up all the data on energy consumption effects of the earlier start of daylight savings time (I've heard this week that some preliminary studies are showing there's actually been an increase in energy consumption because people have been cranking up the heat more in the morning when waking up while it's still cold and dark out...makes sense to me...when I'm sleep-deprived, I get cold too, and have been cranking the heat higher in the mornings to compensate...and having an extra hour of light in the evenings when it's still cold has no benefit, because I'm still inside with the lights on, not outside enjoying warmth and sunshine).
     
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