On Wed, 05 Mar 2008 10:02:51 +0000 (GMT) someone who may be "Dave
Liquorice" wrote this:-

Well it's not dark by 1700 but that is a rather sweeping statement. What
powers the compressors/pumps for you mains gas or water supply?

I was told last year that Scottish Water is the second largest
consumer of Electricity in the country. I can believe it, though
they do seem to use gravity whenever possible.

Of course they can decide to purchase some or all of the electricity
from renewable sources
http://www.scottishpower.com/PressReleases_591.htm


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

"Dave Liquorice" wrote in message
ll.net...
On Tue, 4 Mar 2008 17:07:58 -0000, Mary Fisher wrote:

Off to make dinner now, not depending on electricity of any kind.

Well it's not dark by 1700 but that is a rather sweeping statement. What
powers the compressors/pumps for you mains gas or water supply?

You're making assumptions :-)

Mary

The message
from David Hansen contains these words:

I don't think you can point me at any published
figures (you certainly haven't tried) that indicate that any of the
established wind farms can claim as much as 35%

I have come across capacity factors for wind farms up to ISTR 49%,
over a period of several years. However, that was on an island
exposed to more wind than even Northern Ireland (where the highest
capacity factors in the UK are recorded) and is not indicative of
what will be achieved elsewhere. However, Scottish Power quote
capacity factors of 35%-40% for their modern wind farms.

Do they? Seem not to on their website. And what google comes up with is
a very mixed bag. As I have said before it seems the dominant element in
load factor is wind (or lack of it). The Western Isles are a
particularly favoured location although it seems Shetland is even better
and perhaps a wind farm on Rockall or closer to home on St Kilda would
be better still. Shame it isn't an economic proposition to ship in
energy from the far flung locations.

The average capacity factor for UK onshore wind farms actually fell for
a period after 1998 and still hadn't struggled back to 1998 levels in
2004. That is partly due to the decline in mean wind speed over the
period but must also be partly do to the continued building of wind
farms in unfavourable locations.

"Conclusions
The regional onshore wind capacity factors in the UK between 1998 and
2004 ranged from 19 per cent in one of the least windy regions in a year
when the wind speed index was low, to 40 per cent in one of the most
windy regions in a year when the wind speed index was high, with the
overall UK average being 29 per cent. The quality of the data varies
over this period but with ROCs data available from 2003 the quality and
consistency of the data improved from this point. Using figures from
both NFFO and ROCs data streams increases the data coverage/capture and
means this analysis encompasses all wind farms in the UK.
The correlation between average UK wind speed and capacity factor in any
given year is good with an R2 value of 0.91."

But don't forget:

"Only aggregated figures can be released publicly under the
confidentiality requirements of ‘National Statistics’. Therefore, where
there were only 1 or 2 wind farms in operation within a particular
region, data for these regions were excluded; eg the South East is not
reported. These regional capacity factors were calculated using the
total capacity and generation within each region."

It reports other work. Nothing wrong with that. However, the flaws
in the RAE work were exposed years ago and I wouldn't put much
confidence in it. [snip]

But you haven't quoted your source

One of them is the UKERC report, section 3.3.2. That concentrates on
the RAE's assumption that dedicated backup would be needed for wind,
which is mince.

More smoke and mirrors.

Load factor is a different issue to the amount of backup required for a
variable source.

I recall another one where the authors said they had interviewed the
authors of the RAE report and they had been somewhat confused about
the different types of backup and were unable to give a convincing
answer about several aspects of their report. It was expressed in
academic language but was very cutting about the RAE's report.

and I don't take anything on trust from you.

Excellent, more personal abuse.

One only has to look at the point above that I have just responded to to
see why I don't trust you.

You are clutching at straws. The passage quoted came as close to
rubbishing the 35% as you are ever likely to see in an academic report
where there is genuine uncertainty in the wind.

People can read the report themselves and consider the veracity of
your assertion.

They can read the section I quoted for that. No need to bogged down in
the waffle.

--
Roger Chapman

In message , Matt
writes
On Sun, 02 Mar 2008 15:12:09 +0000, The Natural Philosopher
wrote:

The average load factor of windfarms is 16%.

Only until this happens

http://www.liveleak.com/view?i=8be_1203819244


Laugh, I almost built a sandcastle.


So did we, a couple of weeks ago

--
geoff

Roger wrote:
The message
from David Hansen contains these
words:

For one turbine.

They do come in groups, and wind doesn't vary significantly across
one installation however large.

The average velocity over a relatively long time period doesn't vary
significantly, though gusts can do and can be watched progressing
past farms on occasion.

However, that's beside the point. While the wind at one farm may be
less than forecast it is likely at the same time to be higher at
another farm.

Your point is beside the point, another red herring in fact. Get the
translation velocity wrong and wind speeds changes will indeed lag or
lead but forecast the wrong wind speed for one place and the
likelihood is that the errors for hundreds of miles around will all
be the same sign since they all depend on the predicted pressure
gradients in the local disturbance.

And errors in forecasting are a minor blot on the landscape compared
with the unavoidable consequence of lack of wind. The 1 hour/90%/5
years nonsense may well be completely accurate but unfortunately it is
completely irrelevant. What matters is the situation at the wind farm
sites but trying to find out any information about the extent of
low/non existent output with the current set-up is possibly
impossible.

I drove almost the whole length of Wales at the end of October last
year. Not a breath of wind the whole way (not even on the top of a few
minor hills) and I doubt very much whether there was a single wind
turbine turning either in Wales or in a sizeable chunk of adjacent
England and winds would have been light even further afield.

I'm all for wind turbines as a part of the mix, but they can only be that.
We do experience periods when anticyclonic weather affects large parts of
the UK at one time.

On Wed, 05 Mar 2008 23:31:55 GMT someone who may be "Clot"
wrote this:-

We do experience periods when anticyclonic weather affects large parts of
the UK at one time.

================================================== ==========================

Winter anticyclones

These, it is alleged, frequently becalm the whole country and cause
problems for the system operator, due to the absence of any wind
power, especially at periods of peak demand. The capacity credit, it
is argued, is therefore zero. However, the Environmental Change
Institute at the University of Oxford was quite clear when appearing
before a House of Lords Select Committee [12]:

"We have looked at that [stationary anticyclones in the middle of
winter over the British Isles] occurring in the wind data and the
wind data does not show it."

Several authors, including National Wind Power, have also found that
peak demand periods actually tend to coincide with above-average
wind plant output [13]. The reason for this is that wind output will
tend to be correlated to periods of high peak demand, as one of the
key factors in determining the load on the electricity system is
wind speed. Cold, windy days will lead to increased demand for
heating.

================================================== ==========================

http://www.sd-commission.org.uk/pages/230505.html Full report,
Annex B.




--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

The message
from "Clot" contains these words:

I'm all for wind turbines as a part of the mix, but they can only be that.
We do experience periods when anticyclonic weather affects large parts of
the UK at one time.

I am not against renewable energy per se, rather the reverse in fact. It
is just that I don't think wind energy is the way to go. Unreliable,
unsightly and overly expensive for what we get. Not characteristics that
automatically elevate it to the top of the preferred option list.

Unlike TNP I am in favour of the Severn Barrage. It is claimed that this
alone could produce 10% of UK electricity demand and while that too
would be intermittent it would, within the limits of neap to spring
tides, be as absolutely dependable as any available, and, together with
a limited number of other sites spread round the coast, could satisfy
the bulk of the electricity demand 24/7.

--
Roger Chapman

Roger wrote:
The message
from "Clot" contains these words:

I'm all for wind turbines as a part of the mix, but they can only be that.
We do experience periods when anticyclonic weather affects large parts of
the UK at one time.

I am not against renewable energy per se, rather the reverse in fact. It
is just that I don't think wind energy is the way to go. Unreliable,
unsightly and overly expensive for what we get. Not characteristics that
automatically elevate it to the top of the preferred option list.

Unlike TNP I am in favour of the Severn Barrage. It is claimed that this
alone could produce 10% of UK electricity demand and while that too
would be intermittent it would, within the limits of neap to spring
tides, be as absolutely dependable as any available, and, together with
a limited number of other sites spread round the coast, could satisfy
the bulk of the electricity demand 24/7.

10% of 30% is still only 3% of the total energy consumed by this country.

That is a VERY high price to pay - the complete destruction of a unique
ecosystem - for 3%.


My position is predicated on the assumption that we have to move almost
entirely away from fossil fuels for everything, *transport included*.

The development of suitable batteries means this is a practical
proposition for the first time ever.

And that energy savings of the order of 60% or more are simply not
achievable socially, economically and politically.

The windmill lobby are still ****ing in the wind when it comes to the
real issues of secure, low carbon, national energy supply. As is Kyoto.

Nuclear technology has world wide appeal: one off projects that work
with a singular feature of one countries geography by and large do not.

Its going to be bad enough transporting effectively 3x the current level
of electricity around a supergrid..let alone damming the severn..in
terms of impact.

John Hutton's statement to the FT yesterday bears this out.
----------------

Britain on nuclear power fast-track
By Jean Eaglesham, Chief Political Correspondent
Published: March 6 2008 02:00 | Last updated: March 6 2008 02:00

The UK's reliance on nuclear power will increase "significantly" over
the next two decades, the business secretary said yesterday as he set
out an expansive vision of the country's atomic future.

John Hutton told the Financial Times he expected the new generation of
nuclear power stations the government wants to see built to supply much
more of the country's electricity than the 19 per cent the existing ones
deliver.

Mr Hutton also dropped the government's previous commitment to
maintaining a minimum 29.9 per cent stake in British Energy, the nuclear
generator.

Ministers have refused to be drawn on the scale of investment in new
nuclear reactors they hope to attract to the UK, saying it is for the
market to decide.

But Mr Hutton made it clear the government would pull out all the stops
to maximise the expansion of nuclear power.

"We need the maximum contribution from nuclear sources in the next 10 to
15 years," Mr Hutton said. Asked if the government wanted the share of
electricity generated from nuclear to increase beyond 19 per cent, he
replied: "That's the ambition we should have . . . I'd be very
disappointed if it's not significantly above the current level."

Replacing the UK's aging stock of reactors is seen as vital to achieving
the government's targets on cutting carbon emissions and reducing
dependence on imported gas.

After nearly a decade of indecision over the move to support a new
generation of nuclear reactors, the government is now determined to
fast-track the replacement of the 10 stations, all but one of which is
due to close by 2023. The first plant could be operational by 2017, a
year ahead of the target set in a white paper in January, Mr Hutton said.

"If we can accelerate the timescale, we should," he said. "We've got to
be completely serious about this . . . we should keep our foot down on
the pedal."

The government may sell its £2bn-plus stake in British Energy, Mr Hutton
suggested, with a decision "in the next few years". Ministers have
previously said they will not sell down the state's 39 per cent stake in
Britain's biggest electricity producer below 29.9 per cent.

"We have to consider for the medium term what view we should take about
holding on to these shares," Mr Hutton said. The government was "clear
that we don't want the taxpayers to be involved in new nuclear investment".

According to Mr Hutton, investors are queuing up for the multi-billion
pound construction programme, on the proviso that the government meets
its commitment to "clear the decks" of regulatory obstacles.

"We're in exactly the right place, I've been very encouraged by the
reaction [from investors]," he said. "It's completely confounded all
those people who said 'it's not going to happen' - it's going to happen
and in a shorter timescale than our critics predicted."

David Hansen wrote:
On Wed, 05 Mar 2008 23:31:55 GMT someone who may be "Clot"
wrote this:-

We do experience periods when anticyclonic weather affects large
parts of the UK at one time.

================================================== ==========================

Winter anticyclones

These, it is alleged, frequently becalm the whole country and cause
problems for the system operator, due to the absence of any wind
power, especially at periods of peak demand. The capacity credit, it
is argued, is therefore zero. However, the Environmental Change
Institute at the University of Oxford was quite clear when appearing
before a House of Lords Select Committee [12]:

"We have looked at that [stationary anticyclones in the middle of
winter over the British Isles] occurring in the wind data and the
wind data does not show it."

Several authors, including National Wind Power, have also found that
peak demand periods actually tend to coincide with above-average
wind plant output [13]. The reason for this is that wind output will
tend to be correlated to periods of high peak demand, as one of the
key factors in determining the load on the electricity system is
wind speed. Cold, windy days will lead to increased demand for
heating.

================================================== ==========================

http://www.sd-commission.org.uk/pages/230505.html Full report,
Annex B.

I'm surprised at this. I wonder how the stats were pulled together. Thanks
for the link. When I've a bit more time I'll read that.

The message
from The Natural Philosopher contains these words:

10% of 30% is still only 3% of the total energy consumed by this country.

That is a VERY high price to pay - the complete destruction of a unique
ecosystem - for 3%.

What is unique about it and why do you think it would be completely destroyed.

I think you have been listening too much to the greenies. The only thing
likely to disappear completely is the Severn Bore and even that isn't
entirely certain.

I don't know where I got the 10% from. The most widely used figure seems
to be 5%.

Whenever I do an internet search these days Wikipedia always seems to
come close to the top. I don't know how biased their entry on the Severn
Barrage is but a look at who is backing the project and who is opposing
it may be significant.

In one corner assorted politicians plus James Lovelock. In the other
mostly the massed (but thin) ranks of the green persuasion plus Lord
Sainsbury.

--
Roger Chapman

Roger wrote:
The message
from The Natural Philosopher contains these words:

10% of 30% is still only 3% of the total energy consumed by this country.

That is a VERY high price to pay - the complete destruction of a unique
ecosystem - for 3%.

What is unique about it and why do you think it would be completely destroyed.


It is IIRC the HIGHEST tidal range estuary in the world..thats pretty
unique.

In order yo extract power you need to essentially completely alter the
tidal flow through it.

That is going to lead to a radical change in silt deposition and tidal
scouring..on a level that is probably impossible to predict.

It would also - depending on where it is - cause significant shipping
access problems.

Ther are a huge amount of unkopwns in it..enough to make me shy away
from it completely froma isiness point of view.


I think you have been listening too much to the greenies.

I seldom listen to greenies. Its a bit like watching big brother. Or
Copronation street. There is merely the sick fasciantion ofw atching the
inevitable uselessness of people being consistently wrong about
everything and making silly mistakes over and over again without
learning from them.



The only thing
likely to disappear completely is the Severn Bore and even that isn't
entirely certain.


Depebnd on how you extract the power.

I don't know where I got the 10% from. The most widely used figure seems
to be 5%.


Well thats even more pathetic. ;-)

Whenever I do an internet search these days Wikipedia always seems to
come close to the top. I don't know how biased their entry on the Severn
Barrage is but a look at who is backing the project and who is opposing
it may be significant.

In one corner assorted politicians plus James Lovelock. In the other
mostly the massed (but thin) ranks of the green persuasion plus Lord
Sainsbury.


It will fail on cost probably. Given the choice between investing a
fairly stable and predictable amount in a nuclear power station whose
impact is low and known, and whose costs and output are withing limits
very predictable, and a Severn barrage, whose planning would be
uncertain, whose costs are essentially almost completely unknown, and
whose actual operational efficiency is also a complete unknown, no one
is going to put billions into it unless its not their money.

I would NOT especially eel comfortable about investing in anything that
has to run for years ins a salt water environment..'we've had to pull up
all the turbines to cook the limpets and cockles off them sir'

yeah right..

I cannot off hand think of ONE commercially successful operating tidal
power project. Tho ISTR plenty of 'pilot ones' that never seemed to
attract large scale investment.

There is always a huge risk in doing a 'first' - look at the Chunnel.
Hardly able to pay its interest payments, let alone make any money for
its investors..

On Thu, 06 Mar 2008 13:06:04 GMT someone who may be "Clot"
wrote this:-

I'm surprised at this. I wonder how the stats were pulled together. Thanks
for the link. When I've a bit more time I'll read that.

That report is a good summary of the overall position at the time.

You can download the report on the weather data work from
http://www.eci.ox.ac.uk/publications/downloads/sinden05-dtiwindreport.pdf
In essence they looked at weather records going back to the 1970s
and then compared them the cut in and cut out speeds of wind
turbines. There has been no convincing attack which undermines the
work, though the usual suspects have tried.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

David Hansen wrote:
On Thu, 06 Mar 2008 13:06:04 GMT someone who may be "Clot"
wrote this:-

I'm surprised at this. I wonder how the stats were pulled together. Thanks
for the link. When I've a bit more time I'll read that.

That report is a good summary of the overall position at the time.

You can download the report on the weather data work from
http://www.eci.ox.ac.uk/publications/downloads/sinden05-dtiwindreport.pdf
In essence they looked at weather records going back to the 1970s
and then compared them the cut in and cut out speeds of wind
turbines. There has been no convincing attack which undermines the
work, though the usual suspects have tried.


it all works reaosanbly well when wind turbines are an insignificant
fraction of total capacity, and falls apart if they get to be
significant, when if one area of the countr is becalmed, for sure other
areas wont be, but the net flow of power from where its being produced -
e.g. Scotland - to where its being used - e.g. London would make for a
massively and unnecessarily over specified infrastructure with respect
to the alternatives.

In short the most efficient thing is to generate where you use. Moving
power around uses power. and involves a lot of materials and capital
costs. All conveniently ignored by the likes of Dynamo Hansen and his
ilk.After all if the government subsides the power you generate and the
grid is required to take it wherever you deliver it, its Not Your
Problem is it?


Sadly people who need access to power do not tend to inhabit the wild
desolate windswept reaches of our country, or indeed the North sea.;-)

Windmills are probably fine to generate up to about 10% of the
electricity at no more than 2-3 times the cost of any competing
technology. Beyond that they really have no place at all.

The message
from "Clot" contains these words:

We do experience periods when anticyclonic weather affects large
parts of the UK at one time.

================================================== ==========================

Winter anticyclones

These, it is alleged, frequently becalm the whole country and cause
problems for the system operator, due to the absence of any wind
power, especially at periods of peak demand. The capacity credit, it
is argued, is therefore zero. However, the Environmental Change
Institute at the University of Oxford was quite clear when appearing
before a House of Lords Select Committee [12]:

"We have looked at that [stationary anticyclones in the middle of
winter over the British Isles] occurring in the wind data and the
wind data does not show it."

Several authors, including National Wind Power, have also found that
peak demand periods actually tend to coincide with above-average
wind plant output [13]. The reason for this is that wind output will
tend to be correlated to periods of high peak demand, as one of the
key factors in determining the load on the electricity system is
wind speed. Cold, windy days will lead to increased demand for
heating.

================================================== ==========================

http://www.sd-commission.org.uk/pages/230505.html Full report,
Annex B.

I'm surprised at this. I wonder how the stats were pulled together.

Now who was it who said there were lies, damned lies and statistics?

Disinterested information in this area is hard to come by and may not
even exist.

Sinden has an Agenda but I can't trace the original report to see if the
inserted "[stationary anticyclones in the middle of winter over the
British Isles]" above genuinely reflects his views or is a gross
distortion of the gross distortion in the paragraph above.

Anyone who takes much notice of our weather must know we do from time to
time have high pressure centred over the British Isles and some of these
occur in winter. So how to get round acknowledging it.

"Middle of winter" - 5th Feb or whatever particular day you chose for
middle of winter might just have escaped during the year(s) covered by
the data.

"stationary anticyclones" - scope here for being ruled out either for
being only one in a year or more likely by a pedantic view of
stationary. Weather is dynamic and even blocking highs are never totally
stationary.

"occurring in the wind data" - a single years data chosen on the basis
of, exceptionally, no blocking high.

The first paragraph quoted above by Hansen is a classic, full of strawmen.

Alleged - nothing like casting a little doubt

Frequently - well if nothing else get them on numbers

Becalm the whole country - From Scilly to Shetland, Channel Isles to
Northern Ireland. I would be surprised if a windless high ever came
close to that huge area.

Capacity credit not zero - possibly not but not very much at all is
still not zero.

--
Roger Chapman

Roger wrote:
The message
from "Clot" contains these words:

We do experience periods when anticyclonic weather affects large
parts of the UK at one time.
================================================== ==========================

Winter anticyclones

These, it is alleged, frequently becalm the whole country and cause
problems for the system operator, due to the absence of any wind
power, especially at periods of peak demand. The capacity credit, it
is argued, is therefore zero. However, the Environmental Change
Institute at the University of Oxford was quite clear when appearing
before a House of Lords Select Committee [12]:

"We have looked at that [stationary anticyclones in the middle of
winter over the British Isles] occurring in the wind data and the
wind data does not show it."

Several authors, including National Wind Power, have also found that
peak demand periods actually tend to coincide with above-average
wind plant output [13]. The reason for this is that wind output will
tend to be correlated to periods of high peak demand, as one of the
key factors in determining the load on the electricity system is
wind speed. Cold, windy days will lead to increased demand for
heating.

================================================== ==========================

http://www.sd-commission.org.uk/pages/230505.html Full report,
Annex B.

I'm surprised at this. I wonder how the stats were pulled together.

Now who was it who said there were lies, damned lies and statistics?

Disinterested information in this area is hard to come by and may not
even exist.

Sinden has an Agenda but I can't trace the original report to see if the
inserted "[stationary anticyclones in the middle of winter over the
British Isles]" above genuinely reflects his views or is a gross
distortion of the gross distortion in the paragraph above.

Anyone who takes much notice of our weather must know we do from time to
time have high pressure centred over the British Isles and some of these
occur in winter. So how to get round acknowledging it.

"Middle of winter" - 5th Feb or whatever particular day you chose for
middle of winter might just have escaped during the year(s) covered by
the data.

"stationary anticyclones" - scope here for being ruled out either for
being only one in a year or more likely by a pedantic view of
stationary. Weather is dynamic and even blocking highs are never totally
stationary.

"occurring in the wind data" - a single years data chosen on the basis
of, exceptionally, no blocking high.

The first paragraph quoted above by Hansen is a classic, full of strawmen.

Alleged - nothing like casting a little doubt

Frequently - well if nothing else get them on numbers

Becalm the whole country - From Scilly to Shetland, Channel Isles to
Northern Ireland. I would be surprised if a windless high ever came
close to that huge area.

Capacity credit not zero - possibly not but not very much at all is
still not zero.


I take a lot of notice of the wind, as it directly affects one of my
hobbies. Model aircraft.


Its fairly true to say that there are only maybe a dozen days a year in
which widespread winds below 8mph are to be found. But they do happen. I
treasure them, Its flying weather or the smaller stuff.

Conversely days when teh wind is ubiquitously high, and sustained above
20mph are also very rere - at least inshore.

its also rare to see winds uniformly low across the isles..generally a
ridge or anticyclone is only a 100 miles across at its low wind core
part..so different parts of the country aare almost always experiencinng
dfferent winds.


At the moment there is a weak ridge of high pressure across the isles
between two frontal systems


Wind is westerly and between 10mph and 20mph across the broad area of
the isles. So windfarms probably would operate at around 50% of
capacity. less in the south, more in the north and offshore.

Now tomorrow/saturday its predicted that wind speeds may ouble. Suppose
we were 780% windfarms..what to do?

Do we build to peak capacity and infill with expensive gas turbines for
when the wind is less? or do we build in 6-10 times as much capacity as
we need, so that on overall low wind speed days we can still power the
whole grid?

Its not a question of the AVERAGE load factor. Its a question of the
worst case load factor without having power cuts. I.e. what to do if the
whole country is not operating at 30%, but at say 10%..the more you use
windpower the worse it gets.

And then what to do with all the excess capacity on really quite breezy
days? it cannot be stored..easily or cheaply..


To rely on them for a large proportion of the power generation would
mean transferring something like 50% of the power used in the country at
any given time between the north and the south.

This is not trivial. If we were to go over to wind power on a grand
scale,this would require extremely expensive and sophisticated power
management strategies and a much larger grid infrastructure. There are
signs that this is already and issue in Denmark, where the effective
limits of wind generation are being reached.

The FACTS would seem to be that beyond maybe 20%, hidden wind power
costs* start to escalate: It's already at least twice as expensive as
competing technologies..

The FACT is that its only 'economic'** to use windmills whilst there is
a massive subsidy on them, and they don't get to be a very large part of
the overall generating capacity.


* larger redundant infrastructure, need to build short up/down time gas
turbine plant to cope with fluctuations, or need to build in massive
overcapacity fir calm days.. need for more careful power management
strategies..

** if by economic you mean 'profitable at the taxpayers expense'.

The message
from The Natural Philosopher contains these words:

snip

John Hutton's statement to the FT yesterday bears this out.
----------------

Britain on nuclear power fast-track
By Jean Eaglesham, Chief Political Correspondent
Published: March 6 2008 02:00 | Last updated: March 6 2008 02:00

The UK's reliance on nuclear power will increase "significantly" over
the next two decades, the business secretary said yesterday as he set
out an expansive vision of the country's atomic future.

snip

If the greenies get their way over the Severn barrage they will be in a
stronger position in their stance over nuclear and the greenies are now
arguing that nuclear is incompatible with wind power as it generates
electricity in large chunks which are each either off or flat out.

--
Roger Chapman

The message
from David Hansen contains these words:

You can download the report on the weather data work from
http://www.eci.ox.ac.uk/publications/downloads/sinden05-dtiwindreport.pdf
In essence they looked at weather records going back to the 1970s
and then compared them the cut in and cut out speeds of wind
turbines. There has been no convincing attack which undermines the
work, though the usual suspects have tried.

Doesn't much help if you are looking for actual figures. Scaling off the
graph appears to show that as much as 60% of the UK would have had
insufficient wind to turn a turbine for 5% of the time and nothing at
all is said about the feeble nature of the wind in the rest of the UK
when that is the case. 5% is some 18 days and if the 1 year/5 year
summe/ winter ratio holds there is still approaching 100 hours of winter
generating time when over half the country wouldn't have a single
turbine turning.

--
Roger Chapman

The message
from The Natural Philosopher contains these words:

10% of 30% is still only 3% of the total energy consumed by this country.

That is a VERY high price to pay - the complete destruction of a unique
ecosystem - for 3%.

What is unique about it and why do you think it would be completely
destroyed.


It is IIRC the HIGHEST tidal range estuary in the world..thats pretty
unique.

2nd highest I think but from the pedantic point of view pretty unique is
in the same class as slightly pregnant. It is a singular situation, not
a range, and I wouldn't have it applying to a tidal range unless there
was only the one.

In order yo extract power you need to essentially completely alter the
tidal flow through it.

The current proposal appears to envisage losing the mudflats from half
tide outwards.

That is going to lead to a radical change in silt deposition and tidal
scouring..on a level that is probably impossible to predict.

That sort of thing is carefully modelled these days, possibly even on
computers, although I would be happier if they stuck to real modelling
rather than relying on virtual modelling. Changes in silting patterns
can be advantageous in some cases.

It would also - depending on where it is - cause significant shipping
access problems.

A good many ports are served through locks. It is not the end of the
world and it does have some advantages.

Ther are a huge amount of unkopwns in it..enough to make me shy away
from it completely froma isiness point of view.

No real unknown unkowns (to quote Rumsfield).

I think you have been listening too much to the greenies.

I seldom listen to greenies. Its a bit like watching big brother. Or
Copronation street. There is merely the sick fasciantion ofw atching the
inevitable uselessness of people being consistently wrong about
everything and making silly mistakes over and over again without
learning from them.

I don't have the stomach for either of them.

The only thing
likely to disappear completely is the Severn Bore and even that isn't
entirely certain.


Depebnd on how you extract the power.

I don't know where I got the 10% from. The most widely used figure seems
to be 5%.


Well thats even more pathetic. ;-)

I might need a rethink on that. The Sinden report that Hanson quoted
compared 10% to 5.3 GW of conventional generator capacity and 13 GW of
Wind generator capacity. Wikipedia (again) gives the maximum output of
the 3 most promising lines for the Severn Barrage as 1 GW, 8 GW and 15
GW but enough information to complete the picture is not given at the
same place but a recent scheme was predicted to give 8.64 GW max, 2 GW
average and be 6% overall so 15GW probably does match the 10% I quoted
earlier.


Whenever I do an internet search these days Wikipedia always seems to
come close to the top. I don't know how biased their entry on the Severn
Barrage is but a look at who is backing the project and who is opposing
it may be significant.

In one corner assorted politicians plus James Lovelock. In the other
mostly the massed (but thin) ranks of the green persuasion plus Lord
Sainsbury.


It will fail on cost probably. Given the choice between investing a
fairly stable and predictable amount in a nuclear power station whose
impact is low and known, and whose costs and output are withing limits
very predictable, and a Severn barrage, whose planning would be
uncertain, whose costs are essentially almost completely unknown, and
whose actual operational efficiency is also a complete unknown, no one
is going to put billions into it unless its not their money.

I would NOT especially eel comfortable about investing in anything that
has to run for years ins a salt water environment..'we've had to pull up
all the turbines to cook the limpets and cockles off them sir'

yeah right..

I suspect that is more an issue with off shore wind power.

I cannot off hand think of ONE commercially successful operating tidal
power project. Tho ISTR plenty of 'pilot ones' that never seemed to
attract large scale investment.

The Frogs have been running one sucessfully for years.

There is always a huge risk in doing a 'first' - look at the Chunnel.
Hardly able to pay its interest payments, let alone make any money for
its investors..

If the ferry operators had been competing for business (and hence not
had outrageous margins) before the advent of the Chunnel the Chunnel
would had been a success at least until the tax favoured budget airlines
got in on the act.

--
Roger Chapman

Roger wrote:
The message
from David Hansen contains these words:

You can download the report on the weather data work from
http://www.eci.ox.ac.uk/publications/downloads/sinden05-dtiwindreport.pdf
In essence they looked at weather records going back to the 1970s
and then compared them the cut in and cut out speeds of wind
turbines. There has been no convincing attack which undermines the
work, though the usual suspects have tried.

Doesn't much help if you are looking for actual figures. Scaling off the
graph appears to show that as much as 60% of the UK would have had
insufficient wind to turn a turbine for 5% of the time and nothing at
all is said about the feeble nature of the wind in the rest of the UK
when that is the case. 5% is some 18 days and if the 1 year/5 year
summe/ winter ratio holds there is still approaching 100 hours of winter
generating time when over half the country wouldn't have a single
turbine turning.

Precisely.

Which makes wind energy essentially useless a a large scale part of
electricity generation without some form of carry over energy storage.

Or the ability to run the country off batteries of some sort (including
e.g.pumped storage) for several days on end.

In the limit, that's why you need 6 times as much peak capacity as your
average needs. It could be worse. Let's say that on the bad patches only
40% of your kit is working at only 30% of its rated output.and the rest
ain't working at all..a mere 12% of its 'rated output'

Which is why wind energy will NEVER be more than a small fraction of
generating capacity.

Dynamo Dave keeps spouting on about '30%-35% average load factor' So
what? in the end if your power goes out for 5% of the year, who cares
that your average performance is good.

Heck, I won't tolerate even 0.3% - one DAY of total power cuts.

That's precisely the issues the Danes are finding. The more windmills
they plug into the grid in preference to baseband reliable power, the
more expensive and inefficient gas turbines they need to back them up
when they can't actually do the job.

IF we had a cheap way to store the energy, it would be fine. We
don't..not at the sorts of scales we need. Not for days on end.


The pumped storage systems in place can supply a few percent of total -
they are very useful for smoothing out extremely short duration peaks
and troughs, but not for maintaining huge energy reservoirs.

I suppose you could make hydrogen, and then burn it in gas turbines at
30% efficiency. Not hugely useful..fuel cells at that power level have
never been attempted.

Roger wrote:


There is always a huge risk in doing a 'first' - look at the Chunnel.
Hardly able to pay its interest payments, let alone make any money for
its investors..

If the ferry operators had been competing for business (and hence not
had outrageous margins) before the advent of the Chunnel

The ferries would have been cheaper than they were and therefore...


the Chunnel
would had been a success at least until the tax favoured budget airlines
got in on the act.


??? that seems to be arse about face frankly.


The chunnel wiped out the hovercraft for sure, but the ferries continue
to be cost effective and as cheap as, or cheaper than the chunnel.

What is starting to make it work is high speed capital to capital trains..

I used to commute to Brussels..once..the ferries versus the aircraft,
used to be about an hour or so longer, given the issues of hiring a car
at Heathrow..I was working within taxi/bus distance of Zaventem..

Howver with the sorts of security issues today, I doubt there is any
difference in transit times.

And probably the train would not be a lot worse..

Its a shade over 2 hours on te eurostart..now to get to London from here
probably would take..mm. 45 minutes to the station, say an hour to
london..then an hour in cross laiondon and 'wastage. due to train times
not exactly coinciding, then 2 hours to brussells..and about 45 minutes
oiut to te airport etc.. so about 5 1/2 hours door to door.

IIRC I used to leave here around 5am to get in by 1pm...so 8 hours driving..

About 7 hours on the plane..door to door

The return fare would be around about £115 all in economy including the
car costs..mm. Not too bad with fuel being the price it is now..

Yup. I think next time I go to Brusslels, it would be Eurostar/Chunnel..

"The Natural Philosopher" wrote in message
...

Its a shade over 2 hours on te eurostart..now to get to London from here
probably would take..mm. 45 minutes to the station, say an hour to
london..then an hour in cross laiondon and 'wastage. due to train times
not exactly coinciding, then 2 hours to brussells..and about 45 minutes
oiut to te airport etc.. so about 5 1/2 hours door to door.

Hour to cross London? KX - St Pancras is about 5 minutes walk...

Clive George wrote:
"The Natural Philosopher" wrote in message
...

Its a shade over 2 hours on te eurostart..now to get to London from
here probably would take..mm. 45 minutes to the station, say an hour
to london..then an hour in cross laiondon and 'wastage. due to train
times not exactly coinciding, then 2 hours to brussells..and about 45
minutes oiut to te airport etc.. so about 5 1/2 hours door to door.

Hour to cross London? KX - St Pancras is about 5 minutes walk...

Liverpool st actually. And I said 'wastage..'

If the tubes aren't closed, if the train arrives on time (it never does)..

anyone who expects to get off a train that is targeted to arrive in
Liverpool street on the hour, and catch one that departs St Pancras ten
minutes later, hasn't done it in real life ;-)

The days of 'guaranteed connections' are long gone. One of the reasons
people prefer their cars.

On 2008-03-06 18:14:12 +0000, "Clive George" said:

"The Natural Philosopher" wrote in message
...

Its a shade over 2 hours on te eurostart..now to get to London from
here probably would take..mm. 45 minutes to the station, say an hour to
london..then an hour in cross laiondon and 'wastage. due to train times
not exactly coinciding, then 2 hours to brussells..and about 45 minutes
oiut to te airport etc.. so about 5 1/2 hours door to door.

Hour to cross London? KX - St Pancras is about 5 minutes walk...

With luggage no, and one has to allow check in times at St Pancras.

The Natural Philosopher wrote:

The development of suitable batteries means this is a practical
proposition for the first time ever.


If that were true, we could charge them off the windmills.

Andy

Roger wrote:
The message
from "Clot" contains these words:

I'm all for wind turbines as a part of the mix, but they can only be that.
We do experience periods when anticyclonic weather affects large parts of
the UK at one time.

I am not against renewable energy per se, rather the reverse in fact. It
is just that I don't think wind energy is the way to go. Unreliable,
unsightly and overly expensive for what we get. Not characteristics that
automatically elevate it to the top of the preferred option list.

Unlike TNP I am in favour of the Severn Barrage. It is claimed that this
alone could produce 10% of UK electricity demand and while that too
would be intermittent it would, within the limits of neap to spring
tides, be as absolutely dependable as any available, and, together with
a limited number of other sites spread round the coast, could satisfy
the bulk of the electricity demand 24/7.


Last time this came up, another site in the north was suggested - I
can't remember if it was the Solway, or Morecambe bay, one of those.
But when I dug it turned out the tides were a nice 6 hours away from the
Severn. Which means between them they have a steady generation rate.

The cabling to move the power around is perhaps more of an issue.

Andy

The Natural Philosopher wrote:

Yup. I think next time I go to Brusslels, it would be Eurostar/Chunnel..

I've done train and plane to Paris.

The train wins hands down.

Walk to local station, change platforms at Waterloo (oh drat, they've
broken that!) change platforms at Gare du Nord, take Métro, walk to
company I'm visiting.

Drive to LHR. Park in long-term. Get bus to terminal. Check in. Wait
a couple of hours. Fly to Charles de Gaulle. RER to Gare du Nord, then
it's the same. Terribly broken up.

The Eurostar gives you time for a meal on board as well.

Andy

The message
from Andy Champ contains these words:

Unlike TNP I am in favour of the Severn Barrage. It is claimed that this
alone could produce 10% of UK electricity demand and while that too
would be intermittent it would, within the limits of neap to spring
tides, be as absolutely dependable as any available, and, together with
a limited number of other sites spread round the coast, could satisfy
the bulk of the electricity demand 24/7.


Last time this came up, another site in the north was suggested - I
can't remember if it was the Solway, or Morecambe bay, one of those.
But when I dug it turned out the tides were a nice 6 hours away from the
Severn. Which means between them they have a steady generation rate.

The Severn is undoubtedly the best site but more than one oppo is needed
both because it will take several other sites just to match the Severns
output and because, as at present proposed, the generators would only
work when the tide is flowing and then for only for a part of the time.

The cabling to move the power around is perhaps more of an issue.

Most of the power would be needed in England (Scotland exports power) so
going too far North would increase transmission costs but don't forget
they get tides on the East and South Coasts as well. :-)

--
Roger Chapman

On 2008-03-06 20:52:42 +0000, Andy Champ said:

The Natural Philosopher wrote:

Yup. I think next time I go to Brusslels, it would be Eurostar/Chunnel..

I've done train and plane to Paris.

The train wins hands down.

Walk to local station, change platforms at Waterloo (oh drat, they've
broken that!) change platforms at Gare du Nord, take Métro, walk to
company I'm visiting.

Drive to LHR. Park in long-term. Get bus to terminal. Check in.
Wait a couple of hours. Fly to Charles de Gaulle. RER to Gare du
Nord, then it's the same. Terribly broken up.

The Eurostar gives you time for a meal on board as well.

Andy

Yes, I agree. Far more usable time. If they had wireless working
on the train, even better.

Even with the trek from Waterloo to St Pancras, I still think that it's
interesting although they should have completed the lounge facilities
before opening it.

I'm sure that LHR T5 will be broken on opening as well, but on a far
grander scale. Plenty of opportunity there for them to abuse
customers.

I did win one battle with BAA though. Gradually the notices that tell
their customers:

"Please have your passports and boading cards ready"

are being changed to

"Please have your passport and boarding card ready"


I pointed out to them that I don't have dual nationality and neither am
I traveling on multiple flights at the same time.

Andy Champ wrote:
The Natural Philosopher wrote:

The development of suitable batteries means this is a practical
proposition for the first time ever.


If that were true, we could charge them off the windmills.


At huge expense, yes.

Oh, and it is true. Still expensive, still a bit fragile, but they are
in yer mobile phones and laptops already..



Andy

Roger wrote:
The message
from Andy Champ contains these words:

Unlike TNP I am in favour of the Severn Barrage. It is claimed that this
alone could produce 10% of UK electricity demand and while that too
would be intermittent it would, within the limits of neap to spring
tides, be as absolutely dependable as any available, and, together with
a limited number of other sites spread round the coast, could satisfy
the bulk of the electricity demand 24/7.


Last time this came up, another site in the north was suggested - I
can't remember if it was the Solway, or Morecambe bay, one of those.
But when I dug it turned out the tides were a nice 6 hours away from the
Severn. Which means between them they have a steady generation rate.

The Severn is undoubtedly the best site but more than one oppo is needed
both because it will take several other sites just to match the Severns
output and because, as at present proposed, the generators would only
work when the tide is flowing and then for only for a part of the time.

The cabling to move the power around is perhaps more of an issue.

Most of the power would be needed in England (Scotland exports power) so
going too far North would increase transmission costs but don't forget
they get tides on the East and South Coasts as well. :-)

Yeah..why not put a dam across the channel between dover and calais?

Sod the shipping..who needs it?

Hey, we could make locks and charge the whole or Europe congestion charges!

The message
from The Natural Philosopher contains these words:

Most of the power would be needed in England (Scotland exports power) so
going too far North would increase transmission costs but don't forget
they get tides on the East and South Coasts as well. :-)

Yeah..why not put a dam across the channel between dover and calais?

Sod the shipping..who needs it?

Hey, we could make locks and charge the whole or Europe congestion charges!

Do not mock.

The English Channel is one of the most crowded sea lanes in the world,
if not the most crowded, but at lower traffic densities a barrage just
might have been a valid alternative to the Chunnel. The Suez and Panama
canals function quite well for levels of shipping traffic well in excess
of that for any single port.

--
Roger Chapman

On Thu, 06 Mar 2008 14:13:18 +0000 someone who may be The Natural
Philosopher wrote this:-

it all works reaosanbly well when wind turbines are an insignificant
fraction of total capacity, and falls apart if they get to be
significant,

Then the lights would already be flickering in Scotland and
presumably when we get above 10% they will start going out.

Time will tell, but I predict that when we get to 105 and above the
lights will not go out, at least not due to problems with wind
generated electricity.



--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

Roger wrote:

Last time this came up, another site in the north was suggested - I
can't remember if it was the Solway, or Morecambe bay, one of those.
But when I dug it turned out the tides were a nice 6 hours away from the
Severn. Which means between them they have a steady generation rate.

The Severn is undoubtedly the best site but more than one oppo is needed
both because it will take several other sites just to match the Severns
output and because, as at present proposed, the generators would only
work when the tide is flowing and then for only for a part of the time.

The cabling to move the power around is perhaps more of an issue.

Most of the power would be needed in England (Scotland exports power) so
going too far North would increase transmission costs but don't forget
they get tides on the East and South Coasts as well. :-)


If you can find two similar sized sites with tides 6 hours apart each
one fills in the gaps in the other's output. I don't think there are
any, apart from the Severn, in the SE of the UK with big tides and the
right time difference.

6 hours BTW - I mean 6.5 really, you want the peak flow in one to
coincide with the peak levels in the other. 2 sine waves roughly.

Andy

The Natural Philosopher wrote:
Andy Champ wrote:
The Natural Philosopher wrote:

The development of suitable batteries means this is a practical
proposition for the first time ever.


If that were true, we could charge them off the windmills.


At huge expense, yes.

Oh, and it is true. Still expensive, still a bit fragile, but they are
in yer mobile phones and laptops already..


Those batteries are fine for little gadgets. I wouldn't want to power
London off a set though.

Andy

Andy Champ wrote:
Roger wrote:

Last time this came up, another site in the north was suggested - I
can't remember if it was the Solway, or Morecambe bay, one of those.
But when I dug it turned out the tides were a nice 6 hours away
from the Severn. Which means between them they have a steady
generation rate.

The Severn is undoubtedly the best site but more than one oppo is
needed both because it will take several other sites just to match
the Severns output and because, as at present proposed, the
generators would only work when the tide is flowing and then for
only for a part of the time.
The cabling to move the power around is perhaps more of an issue.

Most of the power would be needed in England (Scotland exports
power) so going too far North would increase transmission costs but
don't forget they get tides on the East and South Coasts as well. :-)


If you can find two similar sized sites with tides 6 hours apart each
one fills in the gaps in the other's output. I don't think there are
any, apart from the Severn, in the SE of the UK with big tides and the
right time difference.

6 hours BTW - I mean 6.5 really, you want the peak flow in one to
coincide with the peak levels in the other. 2 sine waves roughly.


We don't need to find two with diametrically opposed times. Our demands are
irregular and tidal would only be part of the mix - i.e. we should still
have other sources such as CCGT, coal, nuclear, etc.

Personally, I'm a sailor of coastal waters who wears green wellies and don't
find tidal attractive, though I do find the windmills off N Wales ( N Hoyle)
attractive!

As, perhaps, strangely to others, I do find the turbines just N of Cardiff
set out on the hillside a pleasant sight. However, I do appreciate that we
all have different likes and dislikes.

Andy Champ wrote:
Roger wrote:

Last time this came up, another site in the north was suggested - I
can't remember if it was the Solway, or Morecambe bay, one of those.
But when I dug it turned out the tides were a nice 6 hours away from
the Severn. Which means between them they have a steady generation
rate.

The Severn is undoubtedly the best site but more than one oppo is needed
both because it will take several other sites just to match the Severns
output and because, as at present proposed, the generators would only
work when the tide is flowing and then for only for a part of the time.

The cabling to move the power around is perhaps more of an issue.

Most of the power would be needed in England (Scotland exports power) so
going too far North would increase transmission costs but don't forget
they get tides on the East and South Coasts as well. :-)


If you can find two similar sized sites with tides 6 hours apart each
one fills in the gaps in the other's output. I don't think there are
any, apart from the Severn, in the SE of the UK with big tides and the
right time difference.

6 hours BTW - I mean 6.5 really, you want the peak flow in one to
coincide with the peak levels in the other. 2 sine waves roughly.

Andy

engages brain Two highs, two lows a day (roughly) so 4 sets of peak
flow (in and out) which is every 6 hours, so you need two sites with
tides *three* hours apart...

Andy

Andy Champ wrote:
Andy Champ wrote:
Roger wrote:

Last time this came up, another site in the north was suggested - I
can't remember if it was the Solway, or Morecambe bay, one of
those. But when I dug it turned out the tides were a nice 6 hours
away from the Severn. Which means between them they have a steady
generation rate.

The Severn is undoubtedly the best site but more than one oppo is
needed both because it will take several other sites just to match
the Severns output and because, as at present proposed, the
generators would only work when the tide is flowing and then for
only for a part of the time.
The cabling to move the power around is perhaps more of an issue.

Most of the power would be needed in England (Scotland exports
power) so going too far North would increase transmission costs but
don't forget they get tides on the East and South Coasts as well.
:-)

If you can find two similar sized sites with tides 6 hours apart each
one fills in the gaps in the other's output. I don't think there are
any, apart from the Severn, in the SE of the UK with big tides and
the right time difference.

6 hours BTW - I mean 6.5 really, you want the peak flow in one to
coincide with the peak levels in the other. 2 sine waves roughly.

Andy

engages brain Two highs, two lows a day (roughly) so 4 sets of peak
flow (in and out) which is every 6 hours, so you need two sites with
tides *three* hours apart...


Am I missing something? Our demands on the system have peaks that do not
coincide with the lunar cycle of the tides. We need a mix of electricity
generation that can cope with the variations.

The message
from "Clot" contains these words:

engages brain Two highs, two lows a day (roughly) so 4 sets of peak
flow (in and out) which is every 6 hours, so you need two sites with
tides *three* hours apart...

No, ideally we want enough sites with different peaks to provide an
approximately level output 24/7.

Am I missing something? Our demands on the system have peaks that do not
coincide with the lunar cycle of the tides. We need a mix of electricity
generation that can cope with the variations.

Seems to me you are.

Within the constraints of ebb and flow there is some scope for varying
output to match demand.

With your sailors cap on you are also missing the point that there
wouldn't be a great number of these schemes, almost certainly
considerably less than the number of off shore wind farms planned and,
while I am no sailor, I would have thought that off shore wind farms
potentially imposed a far greater blight on coastal sailing than tidal
barrages as well as being a great deal more intrusive in the
land/seascape.

--
Roger Chapman

Roger wrote:
The message
from "Clot" contains these words:

engages brain Two highs, two lows a day (roughly) so 4 sets of
peak flow (in and out) which is every 6 hours, so you need two
sites with tides *three* hours apart...

No, ideally we want enough sites with different peaks to provide an
approximately level output 24/7.

But our demands are not level 24/7 hence the need for pumped storage and
facilities that can be ramped up at short notice.


Am I missing something? Our demands on the system have peaks that do
not coincide with the lunar cycle of the tides. We need a mix of
electricity generation that can cope with the variations.

Seems to me you are.

Within the constraints of ebb and flow there is some scope for varying
output to match demand.

Agreed.


With your sailors cap on you are also missing the point that there
wouldn't be a great number of these schemes, almost certainly
considerably less than the number of off shore wind farms planned and,
while I am no sailor, I would have thought that off shore wind farms
potentially imposed a far greater blight on coastal sailing than tidal
barrages as well as being a great deal more intrusive in the
land/seascape.

I agree that there would be less installations and therefore less intrusive
but impact on the environment? Sailing round offshore turbines could be fun.
We seem to have accepted pylons these days despite their intrusion.

I guess on balance, my concern is that barrages could have a far greater
impact on ecology than offshore windfarms.

The message
from "Clot" contains these words:

Sailing round offshore turbines could be fun.

Ahoy there small sailing vessel approaching down wind. This is the
anti-terrorist protection unit broadcasting on a frequency you won't be
listening to. We have you in our sights and if you don't turn round and
head up wind at least as fast as you are now travelling in this
direction we will blow you out of the water without further ado. You
have 20 seconds to comply with this message. :-)

--
Roger Chapman