another turbine bites the dust.

[charles]

that's the Animal Health & Veterinary Laboratories Agency building (formerly known as Central Veterinary Laboratory).

[dennis]

>>>>>

If you see a factory demolished you will often find a small part left standing to get some advantage when it comes to planning later.

[Nightjar]

Historically, vertical wind turbines have proved to be less reliable than horizontal wind turbines. More recent designs, using helical blades, are said to overcome the problem of blades flexing as they rotate, which causes fatigue and can lead to catastrophic failure. They can, however, stall in gusty conditions.

On the plus side, they need less wind to work, allowing them to be placed lower, which makes servicing them simpler. Low noise levels make them more suitable for use in a residential environment. Also, as they do not slow the air in the same way as a horizontal turbine, they can be placed much closer together. Potentially, this could produce up to ten times the output for a given area of wind farm, despite a lower individual yield.

Colin Bignell

[John Williamson]

No, it *can't* have been the wind. The article says it blew down in a 50 mph gale. The design is claimed in the same artcle to be safe at up to

116 mph.

It'll have been the cold weather over the last week or so weakening the steel, you mark my words. Or the corrosion caused by the last year of continuous rain. Can I take my tongue out of my cheek, now?

[Huge]

Or has already been suggested here, the locals slackening off the bolts ...

[John Williamson]

Dogs mistaking it for a tree could have a similar effect.

[The Natural Philosopher]

I cant find a single pproposition in there that isn't total bollocks

For example if they don't slow the air, they are not producing any power, by definition.

The amount of power you can get out of an area of wind farm is down to swept area of the turbines, the wind speed, the surface area involved and the betz limit.

No cleverness of design can improve on that, and modern turbines get bloody close. Even I qs a convinced skeptic about wiundpower, admit they do teh best possible job they can. Its just that that job is utterly useless. Because wind power itself is utterly useless and no clever technology will make it any different.

If you used physics instead of sales literature to generate your posts, you might be worth paying attention to.

[The Natural Philosopher]

Or the radiation weakened steel (and now cobalt 60 as well) bolts they got from a scrap merchant who pulled them out of Dounreay.

Assuming they actually put all the bolts in..or perhaps some local genius removed them.."Oi do think they will fit moi traccer, Bruce: they wont miss half of un willee?"

[The Natural Philosopher]

Even dogs aren't that stupid.

[Nightjar]

I didn't say they don't slow the air. I said they don't slow the air in the same way. Horizontal turbines need to be spaced at around 10 times their diameter, in order to avoid interference between them. Vertical turbines can be placed much closer together without affecting each other.

Colin Bignell

[Gib Bogle]

That doesn't make sense. As TNP says, the turbine extracts energy from the air, slowing it down. The differences between the downwind wind speed distribution, for the same swept area, will be small, and I'm guessing virtually undetectable after a few diameters.

[Gib Bogle]

I believe the main problem with the vertical axis device (Darrieus rotor) is that the blades experience an oscillating load - towards the axis on the upwind side, away from the axis on the downwind side. This tends to lead to fatigue failure.

[Nightjar]

I am recalling a conversation from a couple of years ago. I assume that the problem is related to tip vortices from the blades of horizontal turbines upsetting the air flow around adjacent turbines, but I didn't go into that much detail at the time. The essential point is that you can put a lot more vertical turbines than horizontal ones into the same size wind farm.

Colin Bignell

[The Natural Philosopher]

Then they are by definition less efficient in themselves.

[The Natural Philosopher]

The point probably is that they have very small swept areas. so low power rating per unit.

Never underestimate greenwash marketing to turn the worst feature of anything into a 'positive design feature'

Like te fact that '70,000 jobs will be created by green energy' or as I would put it, 'green energy will waste 70,000 salaries that could have been doing something productive to keep a set of turbines running that

30 people could have done if it were a STEAM turbine of equivalent overall power'

[Man at B&Q]

Might not be so far from the truth...

[Tim+]

Reminds me of this old Giles cartoon from many years ago.

[Steve Firth]

was so incensed by pylons being put on his land that he pulled them over with his tractor. Back around 1967, so I'm not sure if it influenced Giles.

[Java Jive]

Yes, I was remembering that, but didn't expect to be able to find it online! I used to love Giles' cartoons, and've got a number of the original Giles annuals from many years ago.

I can remember my mother complaining about the pylons all over Scotland: "Damn things! I really don't see why they couldn't bury them!". (I've always assumed she meant just the cables, not the cables as suspended from the pylons.)

Now we see the same th>

>

[Dave Liquorice]

At least pylons are grey (apart from the pink one), are generally below the skyline and stationary.

Windmills tend to be on the skyline waving bloody great white arms at you.