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View Diary: Energy - some good news (for once) (237 comments)

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  •  I have a question (none)
    I have often talked about wind power over family dinners, work lunch's etc and I have recieved one question I'm not able to answer.....you adress it in part in your diary.

    The wind only blows some on the time, what happens when the wind doesn't blow?

    And your point

    "wind power does NOT require "back up" capacity to compensate for the unpredictability of their production - at least not until their reach 20% of total power production, which is definitely not the case in the USA. Denmark is at 20% of its electricity generated by wind and they are coping mostly okay."

    Is the answer we are okay until we reach 20% of total power production?  What more can be said about this common question?

    Also a good answer I have found for the "They're ugly and a blight on the landscape?"

    just return the question and say are they any uglier then power lines?  we don't notice them anymore do we, the windmills will become part of the backgroud soon enough and if they are built offshore then you don't see them.

    •  replies (none)
      • as far as their look is concerned, I personally think that they look quite spectacular. You should obviously put them in front of already-spectacular landscapes, but frankly, over empty farmland, they are certainy visible but not necessarily subjective. At least that's the only "damage" they do and it can be said that it is better than polluted air for instance.

      • as regards intermittence, it is a real issue, but the European experience does suggest that networks can cope fairly easily as long as the proportion of wind in the system is not too high. So yeah, below 20%, it's basically not an issue.

      in the long run, we're all dead (Keynes)

      by Jerome a Paris on Mon Apr 04, 2005 at 07:05:39 AM PDT

      [ Parent ]

      •  Besides... (none)
        ...you can probably up that 20% by quite a bit by just doing things like storing the energy in flywheels, pumping water uphill, etc. It's not like we don't know how to store energy for later use.
        •  To try and explain the 20% "rule"... (4.00)
          First, note that the grid does not currently store any significant amount of electricity.  The electricity that you're using now is being generated, well, now.  Real time.

          This means that the capacity of reliable generation must be at least as large as the largest possible demand -- generally late afternoons in August on a weekday, when the combination of air conditioners all turned on at once (plus other appliances) result in surging demand.

          Now, wind just might not be blowing at that instant, and so it's reliable generation capacity is generally considered to be 0.  This means that other power sources -- gas, oil, coal, hydro, and nuclear -- can't be torn down immediately, even if we had 100% average generation via wind.  Generally speaking, if wind makes up less than 20% of the generation portfolio, the other 80%+ will be enough to be considered sufficient reliable generation capacity.

          Another important question is: how easy is it to adjust the power output of a power plant in real time; that is, how do you adjust the output to match the electricity demands?  Nuclear is the hardest to adjust: they are generally kept at the same level 24 hours a day and provide a baseline.  Coal and oil can be changed, although generally not on a second-by-second rate.  Natural Gas can be adjusted very quickly.  Hydro can be adjusted, but since the fuel is "free", hydro plants try to generate as much electricity as possible.

          So -- in the short term, more wind plants will reduce natural gas consumption, and in a less direct sense, coal and oil.

          One way to reduce the amount of oil and coal plants required is to address peak demand.  When is demand at its highest?  In the day.  This is why solar has promise -- it provides electricity when the grid needs it most.  So, even though its cost per kWh of generation is still unfavorable, it can be used to reduce peak demand, thereby reducing the need to expand capacity.

          Ultimately, the best way to reduce the amount of coal/oil/gas power plants that need to be built is to reduce demand, especially peak demand.  Buy an electronic thermostat so that you can program your heating and cooling, thereby reducing total and peak usage.  Insulate, and insulate well.  Make sure your hot water heater is insulated and well maintained.  Make sure your boiler is well maintained.  Check the gaskets on your fridge -- leaking cool area wastes.  Use compact flurescent bulbs instead of the cheapo incadescents.  Make sure your home doesn't have drafty doors and windows.  Turn of the freakin' light if you're not in the room.

          We can all reduce demand all the while fighting for a better source of supply.

          •  I don't disagree with this... (none)
            ...and I understand that just about all the power being generated is done in real time. But again, why is that necessary?

            This means that the capacity of reliable generation must be at least as large as the largest possible demand -- generally late afternoons in August on a weekday, when the combination of air conditioners all turned on at once (plus other appliances) result in surging demand.

            Nope, it means that the capacity of reliable supply must be at least as large as the largest possible demand.

            Again, you don't need other power supplies to pick up the slack if you just store wind power in high-wind situations in giant flywheels or pumping water uphill or what have you.

            Say your mean wind is 30% of your energy budget. Make your max energy from other sources 70% (alright, say 75% to cover problems). If wind's at 133% of the average, store that energy in flywheels or something, then just draw it down when the wind's not blowing so hard. As long as you have sufficient storage capacity and you can keep losses down to some manageable percentage, then wind will always be, say, 25% of your energy budget (we'll say we lose 5% in inefficiency and storage problems).

            Just because we don't store our electricity, doesn't mean we can't in the future. We have the technology to do that right now.

            •  Yes, supply is the correct word, but... (none)
              energy storage can't be considered a way to improve supply in the near term.  I'm not suggesting that energy storage cannot be done, but...

              1.  Convert to storage medium.  Every time you convert energy from one source to another (for example, electricity to hydro gravitational potential energy), you'll lose some to inefficiency.  

              2.  Storage.  When storing energy, you'll lose some more.  Flywheels have friction.  Lakes suffer from evaporation.  More energy lost.

              3.  Convert from storage medium.  Again, there's less than 100% efficiency, so more lost.

              4.  Retransmit electricity back over power lines a second time.  More energy lost.

              So, while it's not impossible to store energy, the cost of doing so is fairly high, in fixed cost (building flywheels, dams, etc), marginal cost (operating and maintaining equipment), and effeciency (you don't get a MW back for every MW put in).  Given that green-e is already more expensive than coal, storing it is simply out of the question.

              Besides, in your scenario, what happens if the wind doesn't blow for a week straight?  In other words, what happens if a long stretch of wind is preceeded by a long stretch of no wind?  The stored energy might run out before more wind comes along.

              So, energy storage can become part of the solution eventually, but not for a long time from now.  It's too inefficient, too expensive, and doesn't solve the problem of longer-than-average green-e "fuel droughts".

              Even though I'm skeptical of the hydrogen economy coming within the next 15 years, I'd bet that, in general, the hydrogen economy will arrive before green-e is "too much of the supply" in the USA.  Once we start storing energy as hydrogen, extra wind/solar/etc power can be stored as hydrogen, to be used in elec plants or for auto fuel & home fuel, etc.

              In the short term though, it isn't an issue of major concern, since no states are anywhere near 20% of power generation using high variance green-e production.

    •  A better way to say it may be (none)
      You don't even have to bother with backup systems until you get 20% of your power from wind. There are backup systems that can be used, that are also clean, which rely on storing surplus power production until there is demand. Yes, they do increase the initial cost of the system, but it can be done.

      Strangely, I don't really notice most high KV power lines (as long as they are sensibly placed) or wind turbines, so it doesn't matter to me.

      •  I notice (none)
        power lines, towers and wind generators and find them to be among the more attractive of the things we put on the sky line. Spare, efficient structures that accurately show their purpose in life, like a well made bridge, can be beautiful. I was taken with your photographs. Incidently, the 20% limitation only means we have to have four more alternative power sources. We can do that.

        Pithecanthropus "If I pay a man enough money to buy my car, he'll buy my car." Henry Ford

        by johnmorris on Mon Apr 04, 2005 at 07:23:18 AM PDT

        [ Parent ]

        •  Thanks everyone (none)
          While In Ireland 2 years ago I noticed some compliants regarding how the Windmills where ruining the landscape....It was a bit of not in my backyard type feelings but some people had serve feelings against them.  Overall most people said it was a good idea and to be honest they are not unattractive but kinda impressive, moving in unison to the wind....alot better then a smoke stack

          As for the 20% idea, I like it and I also think that if we reached 20% in canada it would be great.....on a slightly related issue in Canada a new promotion has been send out by the Canadian governemnt called the 1 ton challenge....it's kinda neat regarding waste.

          http://oee.nrcan.gc.ca/calendarclub/oneTonne/oneTonne.cfm?PrintView=N&Text=N#

          pass it around to people that may not know how to reduce the energy they use.  I believe it may also be taught in our schools.

          •  Beauty is based in part on social myth (4.00)
            Back in the 50s new factories would intentionally be built as close to the new interstate highways as possible, not so much for ease of transportation, but because at that time most people saw billowing smokestacks as emblems of ecomonic progress and a brighter future for all. Putting one by the highway with your corporate logo attached was great PR.

            Now in New England there is intense opposition to wind farms on some of the ridgelines. A vista "unspoiled" by human intervention is currently an emblem of the survival of nature. There are homes of the rich going up on these same ridges, but current zoning often insists they not be visible from the passing highways, all in name of the illusion.

            So there's a dissonance between the fact that more wind farms will result in a natural world less ruined by us, and the emblematic value of hills appearing to be covered by only trees. Of course, part of the opposition to wind farms is by a contingent who believe that any energy at all is bad, because it only encourage civilization. They regularly contribute letters to the editor to all the papers in the region. Perhaps this is a generational thing, and only their children will ever recognize wind farms as sublimely beautiful.

            •  I think that the movement... (none)
              is part of what makes them beautiful.  Have the people who are opposed to them actually seen a wind farm?  I know some people don't like them of course, but a wind farm is like an extraodinary huge sculpture to me, moving in the wind.

              And I always go back to the fact that I think most people would rather see a wind farm than a coal plant, nuclear reactor, or an oil refinery.  I know which would be more attractive on the California coastline I just visited (hint, the oil refineries are a serious blot on that lovely landscape, and their tar is a lot of little blots all over the beaches).

              "Virginia Woolf's idea of a room of one's own has never been the place for middle- and working-class women. We work with interruptions." - Ananya Chatterjea

              by sarac on Mon Apr 04, 2005 at 12:57:44 PM PDT

              [ Parent ]

    •  A couple of the more plausible (none)
      solutions if wind reaches more than 20% are:

      (1) use the excess power in peak production periods to pump water to the top of a dam from a resevoir at the bottom.  When the wind isn't blowing, use a hydroelectric turbine.  Of course, this isn't 100% effective, but it has the virtue of being very simple.

      (2) have baseline power provided by hydro or nuclear or a fossil fuel, as local circumstances dictate.

      •  Yes, but (none)
        In windy, hot locations the amount of evaporation from stored water can be significant.   I recall a proposed pumped storage project in southern Oregon several years back that died because the available water supply couldn't keep up with predicted evaporation.

        No matter what the ointment, there always seems to be a fly in it...

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