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lurker":va2999go said:
IF global warming comes to be

If? :lol: :lol: :lol: :lol: :lol: :lol: :lol:

can we use all the wind turbines to create a cooling breeze?

Behind the giggle is a wonderful piece of underlying maths. There is a maximum potential for the amount of energy that a wind turbine can take out of the air that passes through it, and, from memory, that is around 21 or 22%. This is one for reductio ad absurdum. Consider what would happen if the turbine removed 100% of the energy from the air as it passed through it. The air in front of the turbine would be moving at Xmph. Say 20mph for the sake of the discussion. The air behind it would be moving at 0 miles per hour. It would be absolutely dead still. After all, that's the definition of the energy content of moving air (potential energy, in physical terms.....not interested in the thermal/ chemical elements). That would mean that in the plane of the blades the wind would decelerate from 20mph to 0 mph, and that can't happen in such a distance. It would also mean that the back edge of the blades were spinning against a plane of stationary gases, without creating a vortex. That can't happen. In short, air has to move through and past the blades to make them spin, and the theoretical maximum amount the air can reduce in speed and still keep the turbines turning is 21/ 22%. Any more than that and the turbines would be slowed, making them into some sort of self-limiting device.
 
RogerS":kcumo0wk said:
.........They already do that. The larger ones have to keep turning else the bearings seize as I understand it. So on a calm day they need electricity to turn.

I can't find anything later than 2012 to substantiate any claims of electricity consumption by turbines, let alone on calm days. Do you have any authoritative evidence for this claim?
 
MikeG.":2m756514 said:
RogerS":2m756514 said:
.........They already do that. The larger ones have to keep turning else the bearings seize as I understand it. So on a calm day they need electricity to turn.

I can't find anything later than 2012 to substantiate any claims of electricity consumption by turbines, let alone on calm days. Do you have any authoritative evidence for this claim?

Sorry Mike,.probably one of those apocryphal stories. I did a quick Google and found an article from the Daily Hate of 2015 but discounted that for obvious reasons !
 
RogerS":1xi7wjp4 said:
MikeG.":1xi7wjp4 said:
RogerS":1xi7wjp4 said:
.........They already do that. The larger ones have to keep turning else the bearings seize as I understand it. So on a calm day they need electricity to turn.

I can't find anything later than 2012 to substantiate any claims of electricity consumption by turbines, let alone on calm days. Do you have any authoritative evidence for this claim?

Sorry Mike,.probably one of those apocryphal stories. I did a quick Google and found an article from the Daily Hate of 2015 but discounted that for obvious reasons !
https://oilprice.com/Alternative-Energy ... s-Use.html

Make your own minds up as to the veracity of the information...
 
Trainee neophyte":3oafqhvq said:
.......Make your own minds up as to the veracity of the information...

It's from 2010. Wind turbines back then were stone aged compared with now. They had gear boxes and stuff.
 
I know someone with a rather massive turbine up the road, it's apparently paid for itself twice over and covered any maintenance in the 10 years or so it's been up as well as powering the whole farm which has the lights on in all the sheds 24/7.
 
Trainee neophyte":1n2e327r said:
Make your own minds up as to the veracity of the information...

I have, there is none. It’s all speculation and no substance. It’s like basing the existence of alien life on a national enquirer article.

Sorry to be so negative about it.

Fitz.
 
Fitzroy":y8ume4gw said:
Trainee neophyte":y8ume4gw said:
Make your own minds up as to the veracity of the information...

I have, there is none. It’s all speculation and no substance. It’s like basing the existence of alien life on a national enquirer article.

Sorry to be so negative about it.

Fitz.

I don't have a turbine, so I have no idea what the running costs are. There will be running costs, but you would hope that these would be less than the generation income. No need to get defensive about running costs -all power generation needs inputs. Nuclear power has way more inputs than outputs, if you include build costs, fuel, and decommissioning costs. Even oil powered generators need maintenance, replacements etc. The cost of doing business. Nothing to be ashamed of. Show me a business with zero costs...
 
Agree there are of course running costs, and some energy is required for auxiliary systems. Just that article does nothing to quantity them.

F.
 
Fitzroy":ykt4ql6m said:
Agree there are of course running costs, and some energy is required for auxiliary systems. Just that article does nothing to quantity them.

F.

Absolutely. Can you find anything that does quantify it? I can tell you that solar panel costs are virtually zero most years. I'm still waiting for my inverter to blow up - it has a 10 year guarantee, which expires soon ( I don't actually know if the supplier still exists to honour the guarantee, and they all have Corona Virus, anyway...) The problem with solar power is the sun goes out, every single day, whereas wind can be almost continuous in the right areas. Wind should beat solar, and hydro should beat both. Fossil fuels beat all of them, for the moment.
 
Trainee neophyte":15n8sgnp said:
Fitzroy":15n8sgnp said:
Agree there are of course running costs, and some energy is required for auxiliary systems. Just that article does nothing to quantity them.

F.

Absolutely. Can you find anything that does quantify it? I can tell you that solar panel costs are virtually zero most years. I'm still waiting for my inverter to blow up - it has a 10 year guarantee, which expires soon ( I don't actually know if the supplier still exists to honour the guarantee, and they all have Corona Virus, anyway...) The problem with solar power is the sun goes out, every single day, whereas wind can be almost continuous in the right areas. Wind should beat solar, and hydro should beat both. Fossil fuels beat all of them, for the moment.

What you need is a Tesla powerwall or two - see: https://www.youtube.com/watch?v=gP51JjnWvLo
 
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