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Offline pavlovs dog

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infinite power!...?
« on: 02/02/2007 22:19:09 »
Hey
Energy alternatives such as wind, solar and HEP are theoretically infinite as long as we humans live with gravity and sunlight...and of course with scientists...
My first question is how power in KWh or GWh and so on, is calculated from wind turbines ???. it would depend on the turning force and turbine efficiency etc, but is there an equation or something to calculate power produced? Diagrams would be helpful

Second, is storing this electrical power possible?(apart from recharging battery cells...unless this is it). if not, is there much research going on to do so?

Cheers
Pavlov's dog himself
...is that a bell i hear?
« Last Edit: 05/02/2007 21:00:08 by pavlovs dog »


 

Offline syhprum

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Re: infinite power!...?
« Reply #1 on: 03/02/2007 05:03:24 »
What I have always thought the most attractive way of storing eletrical power is a pumped hydro scheme such as we have at Ffestiniog

http://www.fhc.co.uk/ffestiniog.htm
 

Offline Soul Surfer

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Re: infinite power!...?
« Reply #2 on: 03/02/2007 09:42:48 »
Natural energy resources are large but not infinite either in quantity or duration but they will do for a long time as long as we can get a lot more control on population growth which is the real problem.

I have had a quick look around the web and not found any really good references on wind power only lots of people trying to sell me one but carefully avoiding telling me how much it would generate.  My  "21st Century smallholder" book (ISBN  190391969/9781903919699) tells me that it costs about 1000 per kilowatt to install a personal wind turbine and that in a good windy site a 1KW generator should provide 80% of an average family'selectricity needs and pay back in about six years but that's not what you want to know.

As far as electrical storage is concerned its batteries for small scale  and the only real large scale processes are pumped hydro or possibly underground gas pressure reservoirs. If anyone found a really good solution to large scale electricity storage it would be great but I fear it is impossible here is an explanation why.

Firstly remember that the forces that hold atoms and molecules together are electrical and that like charges repel each other.  so direct storage of electricity in capacitors is relatively inefficient in that it depends on stressing the structure of the material and they break down at relatively low energies.  Using chemical reactions (such as occur in batteries) uses the energy in the molecular forces more completely but most batteries use fixed quantities of chemicalsand therefore have storage limits.  The best of all are probably the fuel cells where the chemical reagents are separated from the device that generates the electricity and these probably reperesent the best electrical energy storage system. 

After that it is only more indirect techniques like pumped storage where you use up the electricity doing some work like pumping water up a hill and then get it back again by running it back down through a turbine.  Unfortunately there are losses in both directions and the total storage efficiency is quite low.
 

Offline syhprum

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Re: infinite power!...?
« Reply #3 on: 03/02/2007 11:05:29 »
Although the overall efficiency of pumped storage is not very good it makes good economic sense for instance the off peak cost of energy from a nuclear plant that must run continuously is much less than the value of peak time power that the hydro plant can generate as required.
I believe a windmill plant in a good location will average about a quarter of its rated output, probably when you don't want the the power!
« Last Edit: 03/02/2007 11:07:28 by syhprum »
 

Offline Batroost

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Re: infinite power!...?
« Reply #4 on: 05/02/2007 18:56:04 »
The large wind turbines currently being built have a peak output of 3-4 MW. But bear in mind that (in the UK) they average <30% of the peak output. In other words, the just-under 2000 MW of currently installed wind turbines in the UK actually generate around 650MW; or about half as much as a Nuclear Power Station, about 1/6 of Drax coal-fired generation. We've still got a long way to go....
 

Offline syhprum

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Re: infinite power!...?
« Reply #5 on: 05/02/2007 20:44:38 »
Infinite must be the most frequently mispelt word, even well educated persons often spell it 'infinate'.
 

Offline Soul Surfer

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infinite power!...?
« Reply #6 on: 05/02/2007 23:34:25 »
Infinite is also one of the most frequently misused words leading to a lot of misunderstanding when people use it to mean very large and then apply the wierd mathematical rules associated with it to "prove" absurdities.
 

Offline syhprum

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infinite power!...?
« Reply #7 on: 06/02/2007 07:42:44 »
I am pleased to hear on the radio this morning that a 220Km power line is to be built to bring windmill power down from the Scottish highlands, this may well be useful if the project dear to my heart is ever built to import geothermal power from Iceland
 

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infinite power!...?
« Reply #7 on: 06/02/2007 07:42:44 »

 

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