"It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong." Richard P. Feynman

Friday, July 30, 2010

Denmark's Wind Turbines- A Dangerous Amount of Hot Air

 Martin Cohen as part of  his fine article Prophets of Doom looks at the wind generation in Denmark which has been held up to the world as a great example of green power in action. As Martin explains the truth is quite different to the hype.


Denmark is the wind capital of the world - that's one of the reasons why Copenhagen was chosen to host the great climate change conference last year. Between 1985 and 2005, more than 3GW of wind-turbine capacity was installed, of which about 15 per cent was sited offshore.
There are few areas on western Denmark's coast and in its flat or gently rolling countryside that are unaffected. Fortunately, the nation's agricultural community has learned to love the modern intruders - or at least the subsidies.
As the sector expanded, so did the size of the wind turbines. The latest idea is to build 20MW versions as tall as the Eiffel Tower. Each turbine requires an access road, massive concrete foundations and, of course, electricity pylons.
Wind turbines, despite being so very green themselves, are antipathetic to nature. On forested hillsides, they require the clear felling of woodland; on low-lying coastal sites, they necessitate the draining of wetland to facilitate the construction of access roads and enormous concrete foundations.
As independent energy consultant Vic Mason has pointed out, such side-effects could stimulate the oxidation of peat (releasing carbon dioxide) and damage many sensitive habitats essential for particular species of wildlife.
Until recently, the most important subsidy supporting the sector was that the Danish National Grid (and hence consumers) was obliged by law to buy all the electricity produced by wind-power projects - and to do so at prices determined by the government, not the market. That's why Danish householders must pay almost double the UK price for electricity. Estimates of the costs of the subsidies differ - the Danish government says it is about DKr4 billion (£443 million) a year - but independent experts put it at about DKr10 billion a year. If the higher estimates are correct, it would mean that Denmark has been spending more on wind turbines each year than on education.
In spite of the cost, wind power generates only about 4 per cent of the electricity used in Denmark: the truth is that almost all of it is wasted.
Specialists believe that it is unrealistic to expect turbines to produce much more than 20 to 25 per cent of their potential annual output, and that has been the experience in Denmark. Sometimes there is too little wind, sometimes there is too much. Sometimes the machines are broken or being serviced and polished.
With wind turbines, a conventional power station must always provide back-up. For the Danes, traditional power stations with capacities equal to 90 per cent of the installed wind-power capacity must be permanently online to guarantee supply at all times.
But worse still, even when the turbines are busily whirring away, the electricity generally cannot be used. For "technical reasons", as they say, to ensure stability in the domestic grid, most of Denmark's wind power has to be exported at prices well below what it costs to produce. During 2003, 84 per cent of the wind electricity generated was surplus to demand at the moment the wind blew.
Energy specialists calculate that Denmark's exports of electricity to its large, hydro-nuclear-powered neighbours to the north cost local consumers about DKr1 billion each year.
All this combines to explain why, in practice, only 4 per cent of the electricity Danish consumers actually use comes from the turbines. For this miserly contribution to "green thinking", people must pay double the bills.
Nowadays - reneging slightly on its commitment to reduce Denmark's 0.0003 per cent contribution to the CO2 released annually into the atmosphere from the Earth - the Danish government is dismantling its obligatory purchase scheme, although owners of existing wind turbines and district heating plants will continue to receive subsidies. In fact, even after years of spending on an array of wind turbines, Denmark's carbon emissions were rising until recently.
What lessons do the Danish experiences offer us? None, it seems. The UK government is attempting to follow suit. It aspires to a European target of 20 per cent renewable energy by 2020. This nominally equates to about 20,000 2MW wind turbines, along with new systems for energy back-up.
A rule of thumb says that to prevent turbulence from adjacent turbines taking power from each other, they should be separated by up to 10 times their rotor diameter. Thus, the installation of 40GW of wind power in the UK would leave a turbine "footprint" (that is, the land directly appropriated), on land and/or at sea, equivalent in size to almost half the total land area of Wales.
As UK policy in energy is in essence English policy, that might seem like good news - half of Wales is left over for other schemes! Yet the situation is less rosy.
As mentioned, the nominal output of wind power is far greater than the actual output. A more realistic target for the Department of Energy and Climate Change would be the construction of 100,000 wind turbines. Unfortunately, Wales is too small for all those. Instead, a 10km-deep dedicated strip right around the coast of the British Isles would be required. Even Brighton, and its new Green MP, would be blown away ...
The math is really very simple - wind power is not free, it is not reliable ,it is very expensive and despite all the cost does not do what it is claimed to do.

4 comments:

  1. Please find another handle other than Anonymous as it causes confusion with so many people of different opinions using the same name . Your comment is being deleted. Resubmit if you like under another name and it will be welcome.

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  2. Global warming my foot we are at the latter end of the ice age it has been happening for thousands of years, there will be another ice age come upon us in time not our life time I must add, seasons will change etc. What annoys myself is that people are allowing the governments of the world to create lies about global warming they blame it on the so called ozone layer when in fact it was the sun's solar flairs that cause problems apparantly we had this problem over 45,000yrs ago, also the north pole became the south pole because of the earths movement it is moving again hence the sunami's so please anyone telling fibs and blaming this and that on global warming please just get the facts right first and stop stealing from people, and telling lie's .

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  3. It's the governments job to tell lies! The CONDEM coalition only came into being because the liberals got support due to their pledge to abolish tuition fees! They sold their sole to the Devil (Cameron) in a fit of greed for power. And supported Cameron's plan to keep working class people out of the universities by trebling tuition fees. They will not be laughing so loud at the next election!!!!

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  4. I am trying to get my head around the rationale for the Atlantic Array. The other day I admitted to an opponent that I was inclined to support it. That was not overwhelming support but I could not then formulate fully any counter arguments. The case made here certainly poses probing questions.

    I have recently heard that small farm developments are switched off at times because PV generation cannot be easily disconnected. If the turbines don't turn there is no income.

    It is occasionally reported that some producers are paid not to produce. I detect inequity. I perceive that the big commercial developments - typically off-shore - are only viable because of subsidies. Presumably the business plans for these large scale schemes demand payment even when potential electricity cannot be used.

    Bruce

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