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    (Original post by M_E_X)
    A typical capacity factor is 30%, so it's like a 2.3MW power source generating all the time, none stop. It's quite a lot, yeah!
    It's more like a a power source between 0MW and 7.5MW wildly jumping about, that averages to around 2.3MW over a typical year. Here is the total output for the whole country of Ireland:



    A single turbine would have much worse variability.

    (Original post by Fuzzed_Out)
    This just seems like a lot of land to me for relatively low power output, a meter cubed solar panel can be expected to produce about 200W, on a sunny day at noon it can be 600W. I do not know the life expectancy of a wind turbine but a solar panel can be expected to last at least 20 years before it drops below 80 efficiency. I also presume to start up cost will be higher with the solar panels but it just seems you can get so much more energy from the panels for a given land area.
    Solar is far more expensive - around 10x conventional fossil fuels before intermittency costs.
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    (Original post by Hilux)
    x
    Right, so looking at the top graph (over several months and many turbines), it definitely 'averages out' to be fairly constant.

    Do you know how solar, wind and nuclear compare cost-wise?
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    (Original post by M_E_X)
    Right, so looking at the top graph (over several months and many turbines), it definitely 'averages out' to be fairly constant.
    Over a period of months (excluding seasonal variation). The capacity factor is typically calculated as a year average for wind.

    Do you know how solar, wind and nuclear compare cost-wise?
    Wind is competitive with nuclear if you ignore variability, otherwise not. Solar is far more expensive than either.
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    A think the UK should revisit the coal option. The country is sitting on 400 years worth of coal deposits and coal can be burned a lot lot cleaner than it used to be.
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    (Original post by Howard)
    A think the UK should revisit the coal option. The country is sitting on 400 years worth of coal deposits and coal can be burned a lot lot cleaner than it used to be.
    Coal also has a proven capability at providing electricity for mass consumption whereas alternatives except nuclear have proven to be unreliable. 400 years is a lot of resource and we'll probably only need a fraction of it before cheaper, more efficient alternatives are invented (and I don't mean Wind Farms or solar energy).

    If anyone reading wants to apply their brainpower to a proven source of energy that has a good chance at providing a career for them when they leave university - try coal generation. Nobody will want anyone who knows anything about Wind Farms that's for sure.

    They are useless. They will be demolished and sold for scrap and their rare earth elements.
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    (Original post by Hilux)
    After nuclear, according to the graph, which is for some reason excluded from the RO scheme even though the stated aim is to reduce CO2 emissions.
    How much CO2 do you think is expended in the construction and maintainance of a single turbine? Swear Filter faux pas. It's a scam that redistributes wealth to powerful interest groups: large landowners, bankers, industrialists, and the beard brigade (scientists looking for work). RO has nothing to do with CO2 that is why nuclear is ignored... nuclear is tried and tested and well established, the French can do it for us for cheap... no bankers, landowners, industrialists, scientists can wring old ladies and students of their savings for nuclear energy.
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    27% of Scotland's electricity came from renewables last year and at least 75% was from Wind. Surely a well connected enough grid should allow for different areas to supply each other when needed. (thinking on a more European level)
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    (Original post by danielj315)
    27% of Scotland's electricity came from renewables last year and at least 75% was from Wind. Surely a well connected enough grid should allow for different areas to supply each other when needed. (thinking on a more European level)
    We have an interconnector to France. There is a limit to how far you can send electricity though. Perhaps someone could explain the physics behind that but it means it's not possible for Wind Farms in, let's say, Spain to send electricity to Britain when ours stop because there is no wind.

    However, a wider criticism of this is that weather patterns we experience is not always only British. Often when we are in a cold pattern with light winds, it is cold and there are no winds across the whole of Northern Europe. Wind Farms aren't the solution for mass production of electricity.

    Besides, the cost of setting up the spider web of cables would be prohibitive not to mention environmentally destructive.
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    If Wind Farms were so awesome, why are our German friends building high-efficiency coal-fired power stations?

    - EVONIK, Walsum (Duisburg), 800 MW black coal (2010)
    - RWE, Neurath (Cologne), 2 x 800 MW lignite (2009)
    - RWE Westfalen (Dortmund-Hamm, 2 x 800 MW black coal (2011)
    - EON Datteln (Dortmund), 1 x 1100 MW (!) black coal (2011)
    - ENBW Karlsruhe, 1 x 800 MW black coal (2011)
    - Trianel (municipality) Lünen, 1 x 800 MW black coal (2011)
    - Vattenfall Moorburg (Hamburg), 2 x 800 MW black coal (2011)
    - Vattenfall Boxberg (close to Leipzig), 1 x 800 MW lignite (2011)
    - EON, Maasvlakte (Rotterdam), 1 x 1100 MW black coal
    - RWE Eemshaven (NL), 2 x 800 MW black coal.
    If we replaced our coal-fired power stations with the next generation of HE coal-fired power stations we'd save more CO2 than by ordering industrialists to construct and erect and maintain 7,000 new Wind Turbines, each one a CO2 intense activity.

    As I said, this isn't about CO2. This is about siphoning money to vested interests. Bankers, industrialists and big land owners.
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    http://www.aweo.org/windconsumption.html

    Among the wind turbine functions that use electricity are the following:†

    yaw mechanism (to keep the blade assembly perpendicular to the wind; also to untwist the electrical cables in the tower when necessary) -- the nacelle (turbine housing) and blades together weigh 92 tons on a GE 1.5-MW turbine

    blade-pitch control (to keep the rotors spinning at a regular rate)

    lights, controllers, communication, sensors, metering, data collection, etc.

    heating the blades -- this may require 10%-20% of the turbine's nominal (rated) power

    heating and dehumidifying the nacelle -- according to Danish manufacturer Vestas, "power consumption for heating and dehumidification of the nacelle must be expected during periods with increased humidity, low temperatures and low wind speeds"

    oil heater, pump, cooler, and filtering system in gearbox

    hydraulic brake (to lock the blades in very high wind)

    thyristors (to graduate the connection and disconnection between generator and grid) -- 1%-2% of the energy passing through is lost

    magnetizing the stator -- the induction generators used in most large grid-connected turbines require a "large" amount of continuous electricity from the grid to actively power the magnetic coils around the asynchronous "cage rotor" that encloses the generator shaft; at the rated wind speeds, it helps keep the rotor speed constant, and as the wind starts blowing it helps start the rotor turning (see next item); in the rated wind speeds, the stator may use power equal to 10% of the turbine's rated capacity, in slower winds possibly much more

    using the generator as a motor (to help the blades start to turn when the wind speed is low or, as many suspect, to maintain the illusion that the facility is producing electricity when it is not,‡ particularly during important site tours) -- it seems possible that the grid-magnetized stator must work to help keep the 40-ton blade assembly spinning, along with the gears that increase the blade rpm some 50 times for the generator, not just at cut-in (or for show in even less wind) but at least some of the way up towards the full rated wind speed; it may also be spinning the blades and rotor shaft to prevent warping when there is no wind
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    [QUOTE=twl;29247263]We have an interconnector to France. There is a limit to how far you can send electricity though. Perhaps someone could explain the physics behind that but it means it's not possible for Wind Farms in, let's say, Spain to send electricity to Britain when ours stop because there is no wind.

    [\QUOTE]

    Incorrect. If you transform the generated power to DC, you can use buried high voltage HVDC lines. I think the losses are something like 3% per 1000km, so it really is possible, just using different technology.
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    (Original post by Richiboi)
    Incorrect. If you transform the generated power to DC, you can use buried high voltage HVDC lines. I think the losses are something like 3% per 1000km, so it really is possible, just using different technology.
    Is it linear i.e. 3% per 1000km? It could be 3% over the first 1000km, then get more inefficient beyond that distance.

    3% loss itself is far from insignificant though, and when you add on to this the added expense of converting DC current into AC and digging up everything and anything to lay thousands of miles of cables, you're just paying people to do work... which the consumer pays for, and if on to of this you hook the cables up to useless Wind turbines that contain at least 8 components that require electricity from traditional powerstations in order to work, that's not much improving your electricity security IMO.
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    (Original post by twl)
    If Wind Farms were so awesome, why are our German friends building high-efficiency coal-fired power stations?



    If we replaced our coal-fired power stations with the next generation of HE coal-fired power stations we'd save more CO2 than by ordering industrialists to construct and erect and maintain 7,000 new Wind Turbines, each one a CO2 intense activity.

    As I said, this isn't about CO2. This is about siphoning money to vested interests. Bankers, industrialists and big land owners.
    I certainly agree with that. Building 10,000 wind turbines is not Britain's answer to a long term, pragmatic energy equation. Only the UK is considering something this daft.

    (Actually, I've read that 25,000 wind turbines could be required - but you'll need to spend the cost of that again on gas/oil plants for backip for when the wind doesn't blow:rolleyes:)

    However, I think it's unfair to say that "wind power is crap" when it is only meant to supplement an energy portfolio - not relied upon to the extent that the UK is contemplating.

    Coal fired is definatelty the way to go. Britain sits on 400 years worth of the stuff and it can be burned clean these days.
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    (Original post by Howard)
    However, I think it's unfair to say that "wind power is crap" when it is only meant to supplement an energy portfolio - not relied upon to the extent that the UK is contemplating.
    Not saying wind power is crap... if you live in the country and would like a single turbine, go ahead (if you don't mind the look of it).

    I'm saying Wind Farms , Turbine Forests... they are useless. We could get rid of them all, not notice the difference except the extra money in our pockets.
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    (Original post by twl)
    Not saying wind power is crap... if you live in the country and would like a single turbine, go ahead (if you don't mind the look of it).

    I'm saying Wind Farms , Turbine Forests... they are useless. We could get rid of them all, not notice the difference except the extra money in our pockets.
    Again, I'd have to disagree. But I'm a wind farm builder myself (built about 1500MW of the stuff over the last 3 years) so I would say that!
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    As an engineer, I have to say that wind farms are great, as a small percentage of energy production. OP seems to have a personal vendetta against them for some reason. Maybe one killed his favourite racing pigeon :dontknow:
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    (Original post by Nick Longjohnson)
    As an engineer, I have to say that wind farms are great, as a small percentage of energy production. OP seems to have a personal vendetta against them for some reason. Maybe one killed his favourite racing pigeon :dontknow:
    Based on what evidence?

    1. They don't produce any electricity in cold weather.
    2. The blades need to be heated in cold, still weather.
    3. They have over 7 more parts that suck in electricity from the grid.
    4. They make electricity unaffordable killing old people and starving poor students.
    5. They kill rare birds.
    6. They make the landscape look ugly.
    7. When the wind is too strong they are automatically switched-off so they don't break.

    From an intellectual "big boy's toy" POV they might be great.
    From the POV of a money-monger (landowner, banker) they might be great but from a practical point of view producing electricity they are useless.
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    The Lib Dems are ruining this country trying to pander to La-La-Land greens. Nuclear is the way forward. The reason these "environmentalists" won't accept it is because being "green" is like a religion now. If there isn't disaster looming, their whole manifesto is unlikely to appeal to anyone.
    They mention Chernobyl when Russia/Ukraine is known for its awful aeroplane crash rates. Chernobyl was built decades ago. Our country has much better safety records on everything, and this is 2011. Also, considering they're always saying that carbon emissions will kill everyone... surely they should agree with nuclear power then?
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    (Original post by twl)
    Based on what evidence?

    1. They don't produce any electricity in cold weather.
    2. The blades need to be heated in cold, still weather.
    3. They have over 7 more parts that suck in electricity from the grid.
    4. They make electricity unaffordable killing old people and starving poor students.
    5. They kill rare birds.
    6. They make the landscape look ugly.
    7. When the wind is too strong they are automatically switched-off so they don't break.

    From an intellectual "big boy's toy" POV they might be great.
    From the POV of a money-monger (landowner, banker) they might be great but from a practical point of view producing electricity they are useless.
    Points 5 and 6 are hilarious, 6 is totally subjective and 5 is probably false. Evidence for bird deaths please? I don't care about wind power anyway, I'm with the hydrogen fuel cell guys :cool:
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    (Original post by twl)
    Based on what evidence?

    1. They don't produce any electricity in cold weather.
    2. The blades need to be heated in cold, still weather.
    3. They have over 7 more parts that suck in electricity from the grid.
    4. They make electricity unaffordable killing old people and starving poor students.
    5. They kill rare birds.
    6. They make the landscape look ugly.
    7. When the wind is too strong they are automatically switched-off so they don't break.

    From an intellectual "big boy's toy" POV they might be great.
    From the POV of a money-monger (landowner, banker) they might be great but from a practical point of view producing electricity they are useless.
    Correction: They produce no electricity when there is no wind. Also, points 3 and 4 prove you have absolutely no idea what youre talking about. Theyre not switched off in winds that are too strong, they're speed limited.

    OK. Lets take a look at Coal/Oil/Gas fired power stations and how absolutely brilliant they are:

    1. Thermodynamic efficiency of less than 60% in a combined cycle. Often much, much lower (gas turbine is about 40%, with a Rankine 'bottom' cycle it may reach just above 50%)
    2. Fuel is imported from around the world, making it stupid expensive, and having no energy security.
    3. Initial cost is ridiculous
    4. Running cost is ridiculous
    5. Waste heat is pretty much useless unless it can be distributed for heating purposes. Do you want to have a power station in the city?
    6. In a gas turbine, up to 70% of shaft power is used in the air compressor.
    7. In a steam engine, the feed water pump uses almost no energy, but there is immense heat dumped in the condenser as we cannot pump a wet steam mixture.

    This is not even including the environmental points. Fossil fuel powered power stations can kill more than a few rare birds.

    There is a place for all types of power generation. Just because you're sore that there is a farm near your house, doesn't mean the technology is stupid.
 
 
 
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