Posted by Robert Copcutt on December 2, 2009, 7:08 pm
Wind turbines cause turbulence in the air so turbines too close to each
other cause buffeting and this shortens the life of the blades. Without
looking it up again I think David Mackay estimated a maximum of 2W/m2
for average UK wind conditions using current technology. However, these
estimates totally overlook the advantages of using kites which could
deliver a far higher density. They could also be mounted on floating
platforms out to sea thus overcoming any land area limitations. If
someone with a few hundred million to invest had the guts to develop
floating kite technology we could get all our electricity from wind
alone. The same for solar power. There is no shortage of renewable
power, only a shortage of imagination about how to do it.
misterfact@yahoo.com wrote:
> Dr. Howard Hayden (formerly Univ. of Conn.) is going around the radio,
> and lecture circuits making this statement:
>
> "Wind farms produce about 1.2 watts per sq. meter of land area."
>
> Sounds pretty low to me.
>
> There is a 950,000 watt wind-electric-generator near me in Traverse
> City, Mi. It occupies about 3 acres (15,000 sq meters)
>
> Divide 15,000 into 950,000= 63 watts/sq m
>
Firstly it will only generate 950,000 watts in ideal wind conditions.
Its capacity factor could be below 20% so that knocks you down to around
10W/m2.
Secondly, in a farm 3 acres per turbine is tight enough to cause damage
as mentioned above.
Thirdly most land is not suitable for turbines; eg. hills in the way of
the prevailing wind just for a start.
>
> Is Dr. Hayden doing a service to the wind electric industry or not?
>
>
>
> Mike
>
>
>
> Misterfact@yahoo.com
www.copcutt.me.uk
Posted by harry on December 5, 2009, 8:36 pm
wrote:
> Dr. Howard Hayden (formerly Univ. of Conn.) is going around the radio,
> and lecture circuits making this statement:
> "Wind farms produce about 1.2 watts per sq. meter of land area."
> Sounds pretty low to me.
> There is a 950,000 watt wind-electric-generator near me in Traverse
> City, Mi. It occupies about 3 acres (15,000 sq meters)
> Divide 15,000 into 950,000= 63 watts/sq m
> Is Dr. Hayden doing a service to the wind electric industry or not?
> Mike
> Misterf...@yahoo.com
I think the low sounding figure arises from the distance apart they
have to be put to avoid the turbulance from a turbine affecting the
next one down wind of it. Depending on wind direction of course.
And of course the wind not blowing all the time is going to be a major
factor too.
Posted by misterfact@yahoo.com on December 10, 2009, 3:06 pm
> wrote:
> > Dr. Howard Hayden (formerly Univ. of Conn.) is going around the radio,
> > and lecture circuits making this statement:
> > "Wind farms produce about 1.2 watts per sq. meter of land area."
> > Sounds pretty low to me.
> > There is a 950,000 watt wind-electric-generator near me in Traverse
> > City, Mi. It occupies about 3 acres (15,000 sq meters)
> > Divide 15,000 into 950,000= 63 watts/sq m
> > Is Dr. Hayden doing a service to the wind electric industry or not?
> > Mike
> > Misterf...@yahoo.com
> I think the low sounding figure arises from the distance apart they
> have to be put to avoid the turbulance from a turbine affecting the
> next one down wind of it. Depending on wind direction of course.
> And of course the wind not blowing all the time is going to be a major
> factor too.- Hide quoted text -
> - Show quoted text -
All I know is that those 2 kw Mariah (vertical wind turbines) are
advertised to put out AT LEAST 2000kwh per year average, in all
locations where they have been installed
take that figure and divide it by the 9 square meters one of them
takes up and let us know if it's more than i watt per meter. (I'de
say, with varying wind conditions, the genrator averages one fourth
the 2 kw or 500 watts.Divide that by 9 sq. meters and you get 47watts
per sq. meter)
Posted by harry on December 11, 2009, 7:19 pm
wrote:
> > wrote:
> > > Dr. Howard Hayden (formerly Univ. of Conn.) is going around the radio,
> > > and lecture circuits making this statement:
> > > "Wind farms produce about 1.2 watts per sq. meter of land area."
> > > Sounds pretty low to me.
> > > There is a 950,000 watt wind-electric-generator near me in Traverse
> > > City, Mi. It occupies about 3 acres (15,000 sq meters)
> > > Divide 15,000 into 950,000= 63 watts/sq m
> > > Is Dr. Hayden doing a service to the wind electric industry or not?
> > > Mike
> > > Misterf...@yahoo.com
> > I think the low sounding figure arises from the distance apart they
> > have to be put to avoid the turbulance from a turbine affecting the
> > next one down wind of it. Depending on wind direction of course.
> > And of course the wind not blowing all the time is going to be a major
> > factor too.- Hide quoted text -
> > - Show quoted text -
> All I know is that those 2 kw Mariah (vertical wind turbines) are
> advertised to put out AT LEAST 2000kwh per year average, in all
> locations where they have been installed
> take that figure and divide it by the 9 square meters one of them
> takes up and let us know if it's more than i watt per meter. (I'de
> say, with varying wind conditions, the genrator averages one fourth
> the 2 kw or 500 watts.Divide that by 9 sq. meters and you get 47watts
> per sq. meter)
He's talking about the area of LAND taken up, not the size of the
windmill.
This includes the space that has to be between them.
Posted by Michael B on December 11, 2009, 10:36 pm
I'm not impressed with that. Take a drag-style device, that
is not so vulnerable to irregularities of speed and shifts in
direction, and it makes the vertical-style unit the better choice
for urban use. The generator is accessible, it doesn't go faster
than the wind, just needs a generator optimized for low RPM.
So they can be a lot closer together.
> He's talking about the area of LAND taken up, not the size of the
> windmill.
> This includes the space that has to be between them.
> and lecture circuits making this statement:
>
> "Wind farms produce about 1.2 watts per sq. meter of land area."
>
> Sounds pretty low to me.
>
> There is a 950,000 watt wind-electric-generator near me in Traverse
> City, Mi. It occupies about 3 acres (15,000 sq meters)
>
> Divide 15,000 into 950,000= 63 watts/sq m
>