B&Q takes wind turbines off shelves Turbine range withdrawn from sale after
recent survey reveals they don't work as effectively as first thought

http://www.diyweek.net/news/news.asp?id=11999



--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

In message , The Medway
Handyman wrote
B&Q takes wind turbines off shelves Turbine range withdrawn from sale after
recent survey reveals they don't work as effectively as first thought

http://www.diyweek.net/news/news.asp?id=11999


There were many discussions about this form of eco-bollox at the time
that B&Q first started stocking the wind turbines. Studies had already
been published that concluded that in the majority of urban environments
that the energy produced to the £1k investment would be negligible.

--
Alan
news2006 {at} amac {dot} f2s {dot} com

On Thu, 12 Feb 2009 18:38:09 GMT, "The Medway Handyman"
wrote:

B&Q takes wind turbines off shelves Turbine range withdrawn from sale after
recent survey reveals they don't work as effectively as first thought

http://www.diyweek.net/news/news.asp?id=11999

Hmm - I wonder if they'll now give refunds to purchasers on the
grounds of unfitness for purpose. Or perhaps misleading advertising.

--
Frank Erskine

Frank Erskine wrote:
On Thu, 12 Feb 2009 18:38:09 GMT, "The Medway Handyman"
wrote:

B&Q takes wind turbines off shelves Turbine range withdrawn from sale after
recent survey reveals they don't work as effectively as first thought

http://www.diyweek.net/news/news.asp?id=11999

Hmm - I wonder if they'll now give refunds to purchasers on the
grounds of unfitness for purpose. Or perhaps misleading advertising.

There were some purchasers?

--
Rod

Hypothyroidism is a seriously debilitating condition with an insidious
onset.
Although common it frequently goes undiagnosed.
www.thyromind.info www.thyroiduk.org www.altsupportthyroid.org

In article ,
Frank Erskine writes:
On Thu, 12 Feb 2009 18:38:09 GMT, "The Medway Handyman"
wrote:

B&Q takes wind turbines off shelves Turbine range withdrawn from sale after
recent survey reveals they don't work as effectively as first thought

http://www.diyweek.net/news/news.asp?id=11999

Hmm - I wonder if they'll now give refunds to purchasers on the
grounds of unfitness for purpose. Or perhaps misleading advertising.

It sort of implies they will, and says they're even
proactively contacting the purchasers of them to let
them know.

I wonder if they're getting the money back from their
suppliers?

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

"The Medway Handyman" wrote in message
m...
B&Q takes wind turbines off shelves Turbine range withdrawn from sale
after recent survey reveals they don't work as effectively as first
thought

http://www.diyweek.net/news/news.asp?id=11999





This subject has been on my mind for the past 2 days.
All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face of
the blades.

If instead of blades they had the things you see on some wid speed
measurement devices
that have 3 or more cup shaped receptacles on horizontal bars fixed to a
vertical axis.
The wind can hit these assemblies at any angle it chooses with no difference
to the efficiency
of the 'machine'.

I can only conclude that the prevalance of bladed wind turbines means there
is a basic weakness
of the wind-vane method.eg transmission of energy or torque or something
like that.

Anyone got any ideas on this?

Arthur

"geoff" wrote in message
...
In message , Frank Erskine
writes
On Thu, 12 Feb 2009 18:38:09 GMT, "The Medway Handyman"
wrote:

B&Q takes wind turbines off shelves Turbine range withdrawn from sale
after
recent survey reveals they don't work as effectively as first thought

http://www.diyweek.net/news/news.asp?id=11999

Hmm - I wonder if they'll now give refunds to purchasers on the
grounds of unfitness for purpose. Or perhaps misleading advertising.

I'm waiting for them to ban dolphin showers as being unfit for porpoise

--
geoff


{Writes word 'geoff' on piece of paper and discovers has inadvertantly
carved it into laminated desk surface}

Arthur

In message , Frank Erskine
writes
On Thu, 12 Feb 2009 18:38:09 GMT, "The Medway Handyman"
wrote:

B&Q takes wind turbines off shelves Turbine range withdrawn from sale after
recent survey reveals they don't work as effectively as first thought

http://www.diyweek.net/news/news.asp?id=11999

Hmm - I wonder if they'll now give refunds to purchasers on the
grounds of unfitness for purpose. Or perhaps misleading advertising.

I'm waiting for them to ban dolphin showers as being unfit for porpoise

--
geoff

Arthur2 wrote:
"The Medway Handyman" wrote in message
m...
B&Q takes wind turbines off shelves Turbine range withdrawn from sale
after recent survey reveals they don't work as effectively as first
thought

http://www.diyweek.net/news/news.asp?id=11999





This subject has been on my mind for the past 2 days.
All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face of
the blades.

That is why these things have a big tail fin and a turbine body that is
free to rotate - they should always face the wind if there is a nice
steady flow. Needless to say in an urban environment with turbulent flow
they can't ever really face the wind since it gusts from all over the
place.

If instead of blades they had the things you see on some wid speed
measurement devices

Anemometer?


that have 3 or more cup shaped receptacles on horizontal bars fixed to a
vertical axis.
The wind can hit these assemblies at any angle it chooses with no difference
to the efficiency
of the 'machine'.

That is what the tail does really...

http://en.wikipedia.org/wiki/Anemometer



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Thu, 12 Feb 2009 21:51:03 +0000, Arthur2 wrote:
If instead of blades they had the things you see on some wid speed
measurement devices
that have 3 or more cup shaped receptacles on horizontal bars fixed to a
vertical axis.
The wind can hit these assemblies at any angle it chooses with no difference
to the efficiency
of the 'machine'.

I suspect it's a bit harder to 'feather' those sorts of designs so they
don't self-destruct during really high winds. Other than that though, not
sure...

Related note: aren't the "egg beater" vertical turbines supposed to be
more efficient than horizontal-axis ones, and will also (like the
anemometer) work happily with wind blowing from any direction?

On 12 Feb, 21:51, "Arthur2" wrote:

All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face of
the blades.

That's why they can be trimmed into the wind

Or indeed out of it, as one way to survive over-strong winds.

Vertical axis machines have much lower efficiencies in comparision.
They're getting better, and in gusty, crowded urban settings they
might even have the advantage.

"Andy Dingley" wrote in message
...
On 12 Feb, 21:51, "Arthur2" wrote:

All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face
of
the blades.

That's why they can be trimmed into the wind

Or indeed out of it, as one way to survive over-strong winds.

Vertical axis machines have much lower efficiencies in comparision.
They're getting better, and in gusty, crowded urban settings they
might even have the advantage.


Also I think the bladed turbines are more difficult to design mechanically
and maintain.
If the Anemometer had several sets of 'cups' of differing sizes with I
dunno...a sophisticated gearing
system that demesh cup sets if the wind is too strong and optimise for
starting up after a wind drop.

Arthur

wrote:
On Thu, 12 Feb 2009 21:51:03 -0000, "Arthur2"
wrote:


"The Medway Handyman" wrote in
message m...
B&Q takes wind turbines off shelves Turbine range withdrawn from
sale after recent survey reveals they don't work as effectively as
first thought

http://www.diyweek.net/news/news.asp?id=11999





This subject has been on my mind for the past 2 days.
All wind turbines seem to be blades mounted vertically on a
horizontal axle/axis.
These can only be 100% efficient if the wind blows directly onto the
face of the blades.

If instead of blades they had the things you see on some wid speed
measurement devices
that have 3 or more cup shaped receptacles on horizontal bars fixed
to a vertical axis.

I can nly conclude that the prevalance of bladed wind turbines means
there is a basic weakness
of the wind-vane method.eg transmission of energy or torque or
something like that.

Anyone got any ideas on this?

Arthur


Coincidently this design was in the news today at a town not far from
me.
http://news.bbc.co.uk/1/hi/england/dorset/7885680.stm

ISTR the store mentioned has installed them at a number of locations.

One phone in caller made a point that possibly a better way to save
energy would be to shut the store an hour earlier .

Now that is a good point. But this is about greenwash, not saving enegy.

--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

On Feb 13, 8:35*am, "Arthur2" wrote:
"Andy Dingley" wrote in message

...



On 12 Feb, 21:51, "Arthur2" wrote:

All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face
of
the blades.

That's why they can be trimmed into the wind

Or indeed out of it, as one way to survive over-strong winds.

Vertical axis machines have much lower efficiencies in comparision.
They're getting better, and in gusty, crowded urban settings they
might even have the advantage.

Also I think the bladed turbines are more difficult to design mechanically
and maintain.
If the Anemometer had several sets of 'cups' of differing sizes with I
dunno...a sophisticated gearing
system that demesh cup sets if the wind is too strong and optimise for
starting up after a wind drop.

Arthur

Isn't part of the problem that the "cups" have to be driven in reverse
through the air-flow though? So when facing the wind, the cup catches
the air and is driven backwards, but the cup on the exact reverse of
the pole is actually having to go forwards through the wind?

Matt

On 13 Feb, 09:09, wrote:
On Feb 13, 8:35*am, "Arthur2" wrote:



"Andy Dingley" wrote in message

....

On 12 Feb, 21:51, "Arthur2" wrote:

All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face
of
the blades.

That's why they can be trimmed into the wind

Or indeed out of it, as one way to survive over-strong winds.

Vertical axis machines have much lower efficiencies in comparision.
They're getting better, and in gusty, crowded urban settings they
might even have the advantage.

Also I think the bladed turbines are more difficult to design mechanically
and maintain.
If the Anemometer had several sets of 'cups' of differing sizes with I
dunno...a sophisticated gearing
system that demesh cup sets if the wind is too strong and optimise for
starting up after a wind drop.

Arthur

Isn't part of the problem that the "cups" have to be driven in reverse
through the air-flow though? *So when facing the wind, the cup catches
the air and is driven backwards, but the cup on the exact reverse of
the pole is actually having to go forwards through the wind?

Matt

If the cup was a cone or bugle shape the resistance would be reduced
significantly
I would assume.

Arthur

wrote in message
...


Isn't part of the problem that the "cups" have to be driven in reverse
through the air-flow though? So when facing the wind, the cup catches
the air and is driven backwards, but the cup on the exact reverse of
the pole is actually having to go forwards through the wind?

And it has to do so faster than the one going with the wind.
Not ideal for generating power rather than counting revs.

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember geoff saying
something like:

Hmm - I wonder if they'll now give refunds to purchasers on the
grounds of unfitness for purpose. Or perhaps misleading advertising.

I'm waiting for them to ban dolphin showers as being unfit for porpoise

Is this your coat? The one with 'Tarbuck' embroidered on the breast
pocket?

This subject has been on my mind for the past 2 days.
All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face
of the blades.

Can never be 100% efficient. or else you would be left with still air behind
the blades, thus blocking the incoming. Usually significantly less the 50%
efficeincy to allow the air after the blades to have some energy left to
carry it away.

Ian_m wrote:

This subject has been on my mind for the past 2 days.
All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the
face of the blades.

Can never be 100% efficient. or else you would be left with still air
behind the blades, thus blocking the incoming. Usually significantly
less the 50% efficeincy to allow the air after the blades to have some
energy left to carry it away.

around 1-5% actually.

If you take the actual kinetic energy of teh whole wind mass up[ to the
blade tip hight over the windfarm area.

If it were 50% the windmills downwind would stop turning.

In message , Grimly
Curmudgeon writes
We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember geoff saying
something like:

Hmm - I wonder if they'll now give refunds to purchasers on the
grounds of unfitness for purpose. Or perhaps misleading advertising.

I'm waiting for them to ban dolphin showers as being unfit for porpoise

Is this your coat? The one with 'Tarbuck' embroidered on the breast
pocket?

my coat has left without me ...


--
geoff

Jules wrote:
On Thu, 12 Feb 2009 21:51:03 +0000, Arthur2 wrote:
If instead of blades they had the things you see on some wid speed
measurement devices
that have 3 or more cup shaped receptacles on horizontal bars fixed to a
vertical axis.
The wind can hit these assemblies at any angle it chooses with no difference
to the efficiency
of the 'machine'.

I suspect it's a bit harder to 'feather' those sorts of designs so they
don't self-destruct during really high winds. Other than that though, not
sure...

Related note: aren't the "egg beater" vertical turbines supposed to be
more efficient than horizontal-axis ones, and will also (like the
anemometer) work happily with wind blowing from any direction?


I don't believe the Darius rotor is more efficient, but the
multi-directionality is an advantage. Another attraction is that in
principle it could be cheaper to build. Numerous attempts have been
made to design a practical Darius rotor, but none has taken off (so to
speak). One major problem with the design is that the blades experience
oscillating loads as they rotate - on half the cycle to force is towards
the axis, on the other half it is away from it. This tends to cause
fatigue failures in the blades. (I speak with feeling: I am still a
shareholder in a more-or-less defunct company that was started with the
aim of developing a commercially viable Darius rotor.)

Arthur2 wrote:
"The Medway Handyman" wrote in message
m...
B&Q takes wind turbines off shelves Turbine range withdrawn from sale
after recent survey reveals they don't work as effectively as first
thought

http://www.diyweek.net/news/news.asp?id=11999





This subject has been on my mind for the past 2 days.
All wind turbines seem to be blades mounted vertically on a horizontal
axle/axis.
These can only be 100% efficient if the wind blows directly onto the face of
the blades.

If instead of blades they had the things you see on some wid speed
measurement devices
that have 3 or more cup shaped receptacles on horizontal bars fixed to a
vertical axis.
The wind can hit these assemblies at any angle it chooses with no difference
to the efficiency
of the 'machine'.

I can only conclude that the prevalance of bladed wind turbines means there
is a basic weakness
of the wind-vane method.eg transmission of energy or torque or something
like that.

Anyone got any ideas on this?

Arthur



Hopeless efficiency. Extracting energy from the wind requires use of
airfoils and very careful attention to aerodynamics.

On Fri, 13 Feb 2009 08:44:12 GMT, The Medway Handyman wrote:

One phone in caller made a point that possibly a better way to save
energy would be to shut the store an hour earlier .

Now that is a good point. But this is about greenwash, not saving
enegy.

Or even energy. B-)

I doubt 6kW (which is no doubt the maximum rated output) would be enough
to keep half the lights on in a Tesco. They'd save *far* *Far* more energy
by not having the so called 24hrs shopping. I say "so called" 'cause the
one time I did want to shop late at night I went to one of these 24hr
Tescos and it was shut...

--
Cheers
Dave.

Dave Liquorice wrote:
On Fri, 13 Feb 2009 08:44:12 GMT, The Medway Handyman wrote:

One phone in caller made a point that possibly a better way to save
energy would be to shut the store an hour earlier .
Now that is a good point. But this is about greenwash, not saving
enegy.

Or even energy. B-)

I doubt 6kW (which is no doubt the maximum rated output) would be enough
to keep half the lights on in a Tesco. They'd save *far* *Far* more energy
by not having the so called 24hrs shopping. I say "so called" 'cause the
one time I did want to shop late at night I went to one of these 24hr
Tescos and it was shut...

They would still have the lights on for the shelf stackers though...

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Sat, 14 Feb 2009 22:18:10 +0000, John Rumm wrote:

They would still have the lights on for the shelf stackers though...

I doubt it takes all night to restack the shelves, it appears to be a
non-stop process when the store is open. Shelf stackers don't need the
lighting level that is there for the customers either, say 75% would still
be ample. I can't imagine that any of these 24hr stores get many customers
past midnight to say 0600, probably depends on location though but that
comes down to opening when there are customers about, like early or late
to fit with shift changes at a large local employer or nearby market.

--
Cheers
Dave.

Dave Liquorice wrote:
I can't imagine that any of these 24hr stores get many customers
past midnight to say 0600

I used to not infrequently end up in Tescos in Canley about the middle
of that time bracket. Granted, its not going to be as busy as 11 o'clock
on a Saturday morning, but I certainly wasn't shopping alone.

The Tescos near my parents was originally 24-hours when it opened, but
went to "normal" opening hours after a while due to lack of late-night
custom (which doesn't surprise me where my parents live). So they don't
keep them open on some sort of principle - those that open 24-hours do
so because it's economically worth it.

Pete

On Mon, 16 Feb 2009 00:51:30 +0000, Pete Verdon wrote:

Dave Liquorice wrote:
I can't imagine that any of these 24hr stores get many customers past
midnight to say 0600

I used to not infrequently end up in Tescos in Canley about the middle
of that time bracket. Granted, its not going to be as busy as 11 o'clock
on a Saturday morning, but I certainly wasn't shopping alone.



Some 24 hour supermarkets in Germany (I think?) had 'singles nights'
where you could shop for food and friends at the same time...