The message
from The Natural Philosopher contains these words:

There are no large losses from centralised systems.

About 7-8% in the UK, IIRC.

--
Skipweasel
Pay no attention to that man behind the curtain.

The Natural Philosopher wrote:
cupra wrote:
Mary Fisher wrote:
"Roger" wrote in message
k...
Careful, your paranoia about nuclear power is showing.

There's an awful lot of paranoia about wind power in this thread :-)

A lot of it is NIMBYism, but that's opinion based - I wouldn't want
a wind farm nearby but I'm happy with Nuclear!


Me2. In fact we have one. Dungeness 'B'. OK its 40 miles way, but
whats 40 miles in a reactor meltdown?


Mine's a tad closer - we get the evacuation instructions every year


Its a tad ugly from Dunwich, but not arf so ugly as te 'sculptures'
they are proposing to drop in the sea offshore.

As long as they're out of sight, I'm not bothered and no one (within reason)
can complain about the aesthetics - but to place them where they do impact
on the contryscape (whether you like them or not) is something I don't agree
with...

"David Hansen" wrote in message
...
On Fri, 6 Oct 2006 10:44:08 +0100 someone who may be "Doki"
wrote this:-

Wind turbines on top of your house are a load of bull until they become
very
cheap and simple to produce. You'd be better off spending your £1500 on
insulating your house properly and putting in energy saving bulbs, sorting
out all your radiator valves, and getting rid of all the lamp fittings
with
3 or 4 bulbs in and replacing them with one bulb.

What I do is not in the least important to the discussion.

Were I to be asked about such things I would say that there are
other things to do first, including the things you mention. However,
having done that if someone wanted to install a wind turbine on
their house I would point out the advantages and disadvantages of
such a scheme.

I draw my own conclusions about those who loudly imply that someone
should never install a wind turbine on their house.

Put it another way. Buy a wind turbine, save a small amount of energy. Spend
the same amount of cash on insulating next door's house, and you'll save a
lot more energy. But nobody would do that...

Clive George wrote:
"The Natural Philosopher" wrote in message
...
Thats the trouble with localised power generation. Its pro rata more
expensive that centralised - in cash and CO2 generation terms both,
and its not necessarily in the best place for efficiency.

It is if one ignores the large losses from a centralised system.

There are no large losses from centralised systems.

Um, just how efficient do you think the national grid is?


About 97% IIRC.

cheers,
clive

Guy King wrote:
The message
from The Natural Philosopher contains these words:

There are no large losses from centralised systems.

About 7-8% in the UK, IIRC.


I'd have said 2 or 3%, but I won't disagree.

Now look at the losses in a typical local inverter..

More like 20%.

Now look at the cost of a small turbine per MW versus a large one.

Now look at the wind profile on a house roof compared with e.g. off the
west coast of scotland.

Now throw your house mounted generator in the bin, and plant two trees
instead.

"Doki" wrote in message
news


Put it another way. Buy a wind turbine, save a small amount of energy.
Spend the same amount of cash on insulating next door's house, and you'll
save a lot more energy. But nobody would do that...

What if your own house and next door are both fully insulated already?

Doki wrote:


Put it another way. Buy a wind turbine, save a small amount of energy. Spend
the same amount of cash on insulating next door's house, and you'll save a
lot more energy. But nobody would do that...


Which amply proves that small scale turbines are like buying
indulgences..a way to make people feel virtuous that changes nothing.

Mary Fisher wrote:
"Doki" wrote in message
news

Put it another way. Buy a wind turbine, save a small amount of energy.
Spend the same amount of cash on insulating next door's house, and you'll
save a lot more energy. But nobody would do that...

What if your own house and next door are both fully insulated already?

Insulate the cellar and live in that.

On Fri, 6 Oct 2006 23:28:05 +0100, Andy Hall wrote:

Well, they seem big. 115m high.. 30 of them.

115m !!!!! You're joking.... (No you're not).

No he's not. 2MW rated wind turbines are big, *very* big. As a guide
take a Jumbo jet stick an axle through the center point and mount it
on the top of a pole. Most land based wind farms in this country are
using turbines 1/2 to 1/3 this size.

Geez.... I hadn't realised that the offshore ones were this enormous.

And the majority of recently proposed land based turbines are this size
as well. Hub heights of the order of 80m (260') blade lenghts of 40m
(130') overall height 120m (390').

--
Cheers
Dave. pam is missing e-mail

cupra wrote:

A lot of it is NIMBYism, but that's opinion based - I wouldn't want a wind
farm nearby but I'm happy with Nuclear!

I'd put up a wind generator if i could afford it simply to p1ss off the
neighbours.

whilst they are £1500 (installed) now, the price will drop to £700 in
a couple of years. Then, they will become a much more viable
proposition.

harry

Dave Liquorice wrote:

There are enough reports of "illness"(*) increasing in the local
population when a wind farm is built that warrants further investigation.
It is even more disturbing when people suffering from "illness" move away
from the turbine site and their illness goes only to return when back
near the turbines.

there is far more evidence of illness being caused by pylons, mobile
phones and mmr. out of interest do you believe/disbelieve those
'causes'?

harry

"Mr Harry" wrote in message
ups.com...

Dave Liquorice wrote:

There are enough reports of "illness"(*) increasing in the local
population when a wind farm is built that warrants further investigation.
It is even more disturbing when people suffering from "illness" move away
from the turbine site and their illness goes only to return when back
near the turbines.

there is far more evidence of illness being caused by pylons, mobile
phones and mmr. out of interest do you believe/disbelieve those
'causes'?

I don't believe any of them.

Mary

"Owain" wrote in message
...


I have to say I am very impressed with the French electricity. It's not
only cheaper but more reliable.

Oh! That's not what a grandson said when he visited us last week. He lives
somewhere near Limoges and said it was great to be back in England even for
a short time because of the reliable power.

Perhaps it's different by area - as it seems to be here.

Someone from SP tried to tell me it was the same electricity because it
comes down the same cable, but I told him that didn't mean anything
because BBC and ITV both comes down the same aerial and they aren't the
same. Anyway, I got a new meter at the same time so that must filter out
the wrong sort of electricity.

:-) I'd like to think I could remember that!

Mary

Owain

"Mr Harry" wrote in message
oups.com...

cupra wrote:

A lot of it is NIMBYism, but that's opinion based - I wouldn't want a wind
farm nearby but I'm happy with Nuclear!

I'd put up a wind generator if i could afford it simply to p1ss off the
neighbours.

Now that's a good reason - I like it!

But come to think of it they'd just put it down to 'those crazy English!.
They did when they saw us putting a solar water panel on the roof and when
we got chickens and when we ride the scooter and ...

etc.

Mary

The message . com
from "Mr Harry" contains these words:

there is far more evidence of illness being caused by pylons, mobile
phones and mmr.

What, you mean "bugger all" is more than something else? Wow.

--
Skipweasel
Pay no attention to that man behind the curtain.

"Guy King" wrote in message
...
The message . com
from "Mr Harry" contains these words:

there is far more evidence of illness being caused by pylons, mobile
phones and mmr.

What, you mean "bugger all" is more than something else? Wow.

:-)

--
Skipweasel
Pay no attention to that man behind the curtain.

On 7 Oct 2006 09:02:28 -0700, Mr Harry wrote:

there is far more evidence of illness being caused by pylons, mobile
phones and mmr. out of interest do you believe/disbelieve those
'causes'?

Mobile phones *very* doubtful. MMR no my kids got their jabs mid hype.
Pylons, no way would I live under or within 1/4 mile of a big line (above
125kV). Direct personal experience has shown that electromagnetic fields
*do* affect the human body.

--
Cheers
Dave. pam is missing e-mail

On Fri, 06 Oct 2006 17:43:52 +0100, David Hansen wrote:

That quote is out of context

Had they wanted to do that then they are unlikely to have provided a
link to the annex.

The way you included it was out of context. If you dig deep enough on the
BWEA site you can find it in context but only if you dig. The good Dr's
personal comment is always trotted out by pro wind lobby when ever infra
sound is mentioned, presumably on the hope that people don't look to
closely.

I've yet to see any proper research into the matter. Research that
abandons the assumption that "if you can't hear it, it won't hurt you"(*)
and uses preferably a flat measuring scale or the G-weighted one.

(*)Odd that the military have infra sound weapons. If infra sound can't
hurt you what use are weapons using it?

--
Cheers
Dave. pam is missing e-mail

On Fri, 6 Oct 2006 16:56:29 +0100, Andy Hall wrote:

Quite an achievement to do this.

Leaders in the field. B-) Trouble is the Cisco APs and bridges used are
unobtainium and the increasing number of domestic WLANs on 2.4GHz are
becoming a problem. Cash flow is restricting an upgrade of kit to 5.8Ghz
with bigger bandwidths for the backbones.

The biggest real problem we have is the backhaul to the internet. Anyone
know a reliable ISP with good support that can provide a 5 to 10 Mbps
link and won't charge an arm and two legs for traffic levels of 1
Gigabyte/hour download during the day? Evening traffic levels are
probably higher...

I imagine that you don't have the easiest of terrains where you are.

It's not too bad, fairly open rolling fell with valleys but 99% of the
habitation is along the valley bottoms and lower sides. Pick your AP
sites well and you can cover large areas.

--
Cheers
Dave. pam is missing e-mail

On Fri, 06 Oct 2006 16:14:34 +0100, David Hansen wrote:

If you include a quote to support your argument

I did.

failing to standby them when queried seriously weakens your case.

Please indicate where I have failed to standby that quote?

My interpretation of "No I didn't write that."

I have just looked at tariffs for Edinburgh in uswitch.com. Pay on
receipt of bill. The cheapest was Atlantic with 16.40p (and 9.84p
per unit above 900 units per year). The most expensive, ignoring the
green ones was Npower, 21.01p (and 10.45 above 728). While there
have been large increases in prices recently it does show that the
quote was in the right ballpark.

Well TBH my gasted is flabbered. If people are paying those prices they
really are mugs. I've just looked on uswitch for here, Norweb area.
Cheapest "pay on bill" is EDF Standard 13.713 (8.316 over 900kWh).



--
Cheers
Dave. pam is missing e-mail

On Fri, 06 Oct 2006 16:14:34 +0100, David Hansen wrote:

Wrong button before I'd finished... B-)

I have just looked at tariffs for Edinburgh in uswitch.com. Pay on
receipt of bill. The cheapest was Atlantic with 16.40p (and 9.84p
per unit above 900 units per year). The most expensive, ignoring the
green ones was Npower, 21.01p (and 10.45 above 728). While there
have been large increases in prices recently it does show that the
quote was in the right ballpark.

Well to be honest my gasted is well and truely flabbered. If people are
paying those prices they really are mugs. I've just looked on uswitch for
the old Norweb area.

Based on 8400kWh/year usage the cheapest "pay on bill" was EDF Standard
13.713 (8.316 over 900kWh). Most expensive (excluding the greens
Ecotricity and Good Energy) was Southern Electric RSPB Energy at 10.36
plus £22.15/annum standing charge) but that is based on their prices from
Jan 1st 2007, current prices are lower.

If you go for a fixed monthly direct debit things change dramatically and
agin if you choose an online tarrif. I'm pleased to say that Scottish
Power Online Energy is still my best deal at 7.55 plus £47.49/annum
standing charge. The next cheapest is the same company and tarrif but
without (ha ha ha) the standing charge 12.83 (7.55 900) (12.83 - 7.55)
* 900 = £47.52.

Even so the top of the quoted range (16 - 10p) looks low by 4p and the
bottom high by 3p. The range being more like 7 to 20p, which I find quite
incredible and some what distrubing that the postcode lottery applies to
electricity prices to such and extent.

--
Cheers
Dave. pam is missing e-mail

On 2006-10-07 21:44:21 +0100, "Dave Liquorice" said:

On Fri, 6 Oct 2006 16:56:29 +0100, Andy Hall wrote:

Quite an achievement to do this.

Leaders in the field. B-) Trouble is the Cisco APs and bridges used
are unobtainium and the increasing number of domestic WLANs on 2.4GHz
are becoming a problem. Cash flow is restricting an upgrade of kit to
5.8Ghz with bigger bandwidths for the backbones.

If anything Cisco does at least keep products on the market rather
longer than the typical domestic products.

I suppose if you were going to go for a different band/technology,
Alvarion (Breezecom) would be worth a look.

The biggest real problem we have is the backhaul to the internet.
Anyone know a reliable ISP with good support that can provide a 5 to 10
Mbps link and won't charge an arm and two legs for traffic levels of 1
Gigabyte/hour download during the day? Evening traffic levels are
probably higher...

Presumably your main POP is in Alston?

Do any of the providers have LLU equipment in the exchange there?

I guess you've tried the obvious players like Easynet and Pipex?




I imagine that you don't have the easiest of terrains where you are.

It's not too bad, fairly open rolling fell with valleys but 99% of the
habitation is along the valley bottoms and lower sides. Pick your AP
sites well and you can cover large areas.

I guess that there's a limit to what people are willing to pay....

Realistically if they are in a low valley small community in the high
Pennines, they can't expect to get the same price points as someone in
Carlisle.

Since you have traffic shaping, couldn't you offer different bandwidths
and contentions and charge accordingly?

"Doki" wrote in message
news

"David Hansen" wrote in message
...
On Fri, 6 Oct 2006 10:44:08 +0100 someone who may be "Doki"
wrote this:-

Wind turbines on top of your house are a load of bull until they become
very
cheap and simple to produce. You'd be better off spending your £1500 on
insulating your house properly and putting in energy saving bulbs,
sorting
out all your radiator valves, and getting rid of all the lamp fittings
with
3 or 4 bulbs in and replacing them with one bulb.

What I do is not in the least important to the discussion.

Were I to be asked about such things I would say that there are
other things to do first, including the things you mention. However,
having done that if someone wanted to install a wind turbine on
their house I would point out the advantages and disadvantages of
such a scheme.

I draw my own conclusions about those who loudly imply that someone
should never install a wind turbine on their house.

Put it another way. Buy a wind turbine, save a small amount of energy.
Spend the same amount of cash on insulating next door's house, and you'll
save a lot more energy. But nobody would do that...


look at this web site
http://www.scoraigwind.com/citywinds/index.htm

On Fri, 6 Oct 2006 15:23:19 +0100, tony sayer
wrote:

In article , Matt
writes

The whole basis of the design of Dinorwig, designed in the late
60's/early 70's was to cater for the simultaneous failure of the two
largest single generators (not power stations) on the UK grid system
or for the failure of a double circuit 400kV line (with the conductors
available at the time) the former is 1320MW (2 x 660MW), the later
around about 1800MW.

That Dinorwig can generate pretty close to the latter figure starting
from the units "spinning in air" to full load in around 15 seconds
means it will always play a very important part in ensuring system
stability.


Well I always thought it was for the sudden demand for cuppa's during
Corrie;?, but whyda I know!...

Well that as well but I thought everyone knew that! It wasn't as far
as I recall a primary design aim though. Before Dinorwig came on
stream the electricity system coped reasonably ok. Even without any
pumped storage, and assuming the system is not fully utilised
(loaded), spinning reserve in the form of less than fully loaded
generation across the country can cope with just about any ad break
mainly because load pickup during ad breaks is much smaller now than
say 20 years ago. Football matches and dead royals make the biggest
impact on the load profile - perhaps a good reason for getting rid of
both.


--

On Fri, 6 Oct 2006 14:45:21 +0100, Roger
wrote:

The message
from David Hansen contains these words:

As I said, Sloy is an example of a hydro station that is used to lop
peaks. Hydro stations are extremely flexible and thus can be used
for several tasks. For example two of the units at Dinorwig could be
in immediate response mode to cover failures while the other four
are supplying the grid.

Direct line to every power station in the country, I don't think so. All
Dinorwig can do is supply the grid.

No "direct line" is needed. Just like all the other generation
regardless of power source Dinorwig has a governor that will instruct
the output to increase as the grid system frequency falls. Also other
means are available to automatically request Dinorwig generation with
the press of two buttons (I'll keep the precise details of that under
wraps though)

You will agree that Sizewell B is rated at 1320MW, or so and is the
largest single point failure?

No. Why should I when most modern coal fired stations are 2000MW nominal
or larger and Drax is 4000MW.

Those power stations do not represent a single point of failure,
because there are a number of boilers, turbines and transformers.

You moved the goal posts, I just moved them back to where they were, but
it doesn't take a genius to come up with a scenario where a whole power
station has to be taken off line.

No, the biggest failures that the system is designed for are

a) the simultaneous loss of the TWO largest generators on the system.
NOT POWER STATIONS

b) the simultaneous loss of TWO overhead lines

Failures that could cause the loss of more generation/transfer
capacity than this are not considered likely, but there are systems
and procedures in place to ensure the lights stay on regardless of the
availability of any specific generation and that includes Dinorwig.

When the hydrogen cooling the generator at Drax leaked out and went
bang, bearing oil caught fire and then huge holes started appeared in
the turbine hall roof from the flames, the other five units continued
generating despite a scene from Armageddon just tens of yards away.
On another occasion when a generator transformer exploded, the other
units also continued generating. So in both cases the 4000MW output
dropped by just 660MW. Spin up Dinorwig to cater for immediate
frequency support and then pull up the output by just 20 MW a piece
across the other 500/660MW units in around 10 minutes and the
frequency stops more or less bang on 50Hz. An absolute piece of ****.

When the transformers at one location decided it was bonfire night and
a number were totally destroyed by an oil fire - the whole substation
was remotely isolated, the effects other than in the immediate
vicinity were minimal. At another location when switchgear decided to
partly operate followed immediately by catastrophic explosion, the
backup capacity and reconfigurability meant the load to customers
returned within 45 minutes. Parts of the substation was reminiscent
of a B52 bomb strike, huge bits of shapnel flew hundreds of metres and
embedded themselves into walls and trees, some parts were never found.

When a mobile crane driver left his jib up and shorted out the
overhead lines at Hartlepool, exploding all his tyres, blowing a hole
30 feet across and 10 feet deep in the tarmac, the generation of
1320MW was lost, Dinorwig came online from zero output in just over a
minute - they were manually instructed from grid control on them
seeing falling grid frequency, from indication of the overhead line
circuit failing and from loss of generation. No lights went out
although the crane driver saw his life flash before him. If you were
in earshot you might have heard a bang, if you were watching telly
with the sound turned up you wouldn't have noticed a thing.

Even with the grid system completely split north/south in the
"hurricane" of 1987, with multiple repeated double circuit line faults
AND two almost simultaneous double circuit line faults the power
system survived and kept most of the lights on. Some switchgear was
operated more times in one day than in 10 years of normal operation.
The output from Dinorwig was up and down faster than a whore's
knickers. Yes you might have had no lights or standing trees in leafy
Surrey, but the rest of the country went to work as normal.

So, no "Direct line to every power station in the country" but 20
years of operational experience says that the current operating regime
is correct.




--

On Sun, 08 Oct 2006 08:12:24 +0100, Matt
wrote:


|No "direct line" is needed. Just like all the other generation
|regardless of power source Dinorwig has a governor that will instruct
|the output to increase as the grid system frequency falls. Also other
|means are available to automatically request Dinorwig generation with
|the press of two buttons


The Grid frequency does not actually need to fall for Dinorwig or any other
power station to feed power to the grid. All that is required is to
increase the mechanical power to the generators, which will feed more
Electrical power to the grid, or in Dinowigs case absorb power to pump
water from the lower reservoir to the upper. Grid frequency is a complex
and difficult function of all the generators on line at the time and is
controlled *very* closely. The amount of power supplied by any power
station nowadays is controlled by commercial contracts.

AFAIK the generators are normally synchronised and spinning when Dinorwig
is waiting to supply power to the grid. All that is required is to open
the sluice gates, and then make sure that everything is under control.

| (I'll keep the precise details of that under
|wraps though)

The methods used are available to anyone who cares to get say a BSc in
Electrical Engineering, When I did the tour some years ago, the
explanations were very good.
--
Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst*
method of accessing usenet. GG subscribers would be well advised get a
newsreader, say Agent, and a newsserver, say news.individual.net. These
will allow them: to see only *new* posts, a killfile, and other goodies.

On 2006-10-08, Matt wrote:
On Fri, 6 Oct 2006 14:45:21 +0100, Roger
wrote:

The message
from David Hansen contains these words:

As I said, Sloy is an example of a hydro station that is used to lop
peaks. Hydro stations are extremely flexible and thus can be used
for several tasks. For example two of the units at Dinorwig could be
in immediate response mode to cover failures while the other four
are supplying the grid.

Direct line to every power station in the country, I don't think so. All
Dinorwig can do is supply the grid.

No "direct line" is needed. Just like all the other generation
regardless of power source Dinorwig has a governor that will instruct
the output to increase as the grid system frequency falls. Also other
means are available to automatically request Dinorwig generation with
the press of two buttons (I'll keep the precise details of that under
wraps though)

A friend visited Dinorwig this summer. He reported that they can meet
unexpected demand surges within 90 seconds. If they have advance warning
it can be done within 10.

--
John Phillips

On Sun, 08 Oct 2006 08:07:40 +0100, Matt
wrote:


|Well that as well but I thought everyone knew that! It wasn't as far
|as I recall a primary design aim though. Before Dinorwig came on
|stream the electricity system coped reasonably ok. Even without any
|pumped storage, and assuming the system is not fully utilised
|(loaded), spinning reserve in the form of less than fully loaded
|generation across the country can cope with just about any ad break
|mainly because load pickup during ad breaks is much smaller now than
|say 20 years ago. Football matches and dead royals make the biggest
|impact on the load profile - perhaps a good reason for getting rid of
|both.

Spinning reserve with a coal or gas fired power station running at less
than full load costs a lot of waste heat, which is of course money.
The advantage of Dinowgig is that it costs very little when not generating
it used very little power/money.
--
Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst*
method of accessing usenet. GG subscribers would be well advised get a
newsreader, say Agent, and a newsserver, say news.individual.net. These
will allow them: to see only *new* posts, a killfile, and other goodies.

The message
from Matt contains these words:

As I said, Sloy is an example of a hydro station that is used to lop
peaks. Hydro stations are extremely flexible and thus can be used
for several tasks. For example two of the units at Dinorwig could be
in immediate response mode to cover failures while the other four
are supplying the grid.

Direct line to every power station in the country, I don't think so. All
Dinorwig can do is supply the grid.

No "direct line" is needed. Just like all the other generation
regardless of power source Dinorwig has a governor that will instruct
the output to increase as the grid system frequency falls. Also other
means are available to automatically request Dinorwig generation with
the press of two buttons (I'll keep the precise details of that under
wraps though)

You misunderstood what I meant. David has it that 2 units could cover
failures while the other 4 supply the grid. I was suggesting that all
Dinorwig can do is what all other power stations connected to the grid
do - supply the grid.

You will agree that Sizewell B is rated at 1320MW, or so and is the
largest single point failure?

No. Why should I when most modern coal fired stations are 2000MW nominal
or larger and Drax is 4000MW.

Those power stations do not represent a single point of failure,
because there are a number of boilers, turbines and transformers.

You moved the goal posts, I just moved them back to where they were, but
it doesn't take a genius to come up with a scenario where a whole power
station has to be taken off line.

No, the biggest failures that the system is designed for are

That's as maybe but David was responding to my post which stipulated a
whole power station.

a) the simultaneous loss of the TWO largest generators on the system.
NOT POWER STATIONS

b) the simultaneous loss of TWO overhead lines

Failures that could cause the loss of more generation/transfer
capacity than this are not considered likely, but there are systems
and procedures in place to ensure the lights stay on regardless of the
availability of any specific generation and that includes Dinorwig.

When the hydrogen cooling the generator at Drax leaked out and went
bang, bearing oil caught fire and then huge holes started appeared in
the turbine hall roof from the flames, the other five units continued
generating despite a scene from Armageddon just tens of yards away.
On another occasion when a generator transformer exploded, the other
units also continued generating. So in both cases the 4000MW output
dropped by just 660MW. Spin up Dinorwig to cater for immediate
frequency support and then pull up the output by just 20 MW a piece
across the other 500/660MW units in around 10 minutes and the
frequency stops more or less bang on 50Hz. An absolute piece of ****.

When the transformers at one location decided it was bonfire night and
a number were totally destroyed by an oil fire - the whole substation
was remotely isolated, the effects other than in the immediate
vicinity were minimal. At another location when switchgear decided to
partly operate followed immediately by catastrophic explosion, the
backup capacity and reconfigurability meant the load to customers
returned within 45 minutes. Parts of the substation was reminiscent
of a B52 bomb strike, huge bits of shapnel flew hundreds of metres and
embedded themselves into walls and trees, some parts were never found.

When a mobile crane driver left his jib up and shorted out the
overhead lines at Hartlepool, exploding all his tyres, blowing a hole
30 feet across and 10 feet deep in the tarmac, the generation of
1320MW was lost, Dinorwig came online from zero output in just over a
minute - they were manually instructed from grid control on them
seeing falling grid frequency, from indication of the overhead line
circuit failing and from loss of generation. No lights went out
although the crane driver saw his life flash before him. If you were
in earshot you might have heard a bang, if you were watching telly
with the sound turned up you wouldn't have noticed a thing.

Even with the grid system completely split north/south in the
"hurricane" of 1987, with multiple repeated double circuit line faults
AND two almost simultaneous double circuit line faults the power
system survived and kept most of the lights on. Some switchgear was
operated more times in one day than in 10 years of normal operation.
The output from Dinorwig was up and down faster than a whore's
knickers. Yes you might have had no lights or standing trees in leafy
Surrey, but the rest of the country went to work as normal.

So, no "Direct line to every power station in the country" but 20
years of operational experience says that the current operating regime
is correct.

All very interesting but built on a misunderstanding of the point I was
trying to make - that as a generator Dinorwig supplies the grid, not
individual power stations. To the extent that anything is independent on
an interconnected system it will be satisfying the load closest to it
which is unlikely to be the same load that the disconnected power
station was satisfying.

--
Roger Chapman

Matt wrote:
Football matches and dead royals make the biggest
impact on the load profile - perhaps a good reason for getting rid of
both.


But dead royals have already been got rid of haven't they?

Matt wrote:
On Fri, 6 Oct 2006 14:45:21 +0100, Roger
wrote:

The message
from David Hansen contains these words:

As I said, Sloy is an example of a hydro station that is used to lop
peaks. Hydro stations are extremely flexible and thus can be used
for several tasks. For example two of the units at Dinorwig could be
in immediate response mode to cover failures while the other four
are supplying the grid.
Direct line to every power station in the country, I don't think so. All
Dinorwig can do is supply the grid.

No "direct line" is needed. Just like all the other generation
regardless of power source Dinorwig has a governor that will instruct
the output to increase as the grid system frequency falls. Also other
means are available to automatically request Dinorwig generation with
the press of two buttons (I'll keep the precise details of that under
wraps though)

You will agree that Sizewell B is rated at 1320MW, or so and is the
largest single point failure?
No. Why should I when most modern coal fired stations are 2000MW nominal
or larger and Drax is 4000MW.
Those power stations do not represent a single point of failure,
because there are a number of boilers, turbines and transformers.
You moved the goal posts, I just moved them back to where they were, but
it doesn't take a genius to come up with a scenario where a whole power
station has to be taken off line.

No, the biggest failures that the system is designed for are

a) the simultaneous loss of the TWO largest generators on the system.
NOT POWER STATIONS

b) the simultaneous loss of TWO overhead lines

Failures that could cause the loss of more generation/transfer
capacity than this are not considered likely, but there are systems
and procedures in place to ensure the lights stay on regardless of the
availability of any specific generation and that includes Dinorwig.

When the hydrogen cooling the generator at Drax leaked out and went
bang, bearing oil caught fire and then huge holes started appeared in
the turbine hall roof from the flames, the other five units continued
generating despite a scene from Armageddon just tens of yards away.
On another occasion when a generator transformer exploded, the other
units also continued generating. So in both cases the 4000MW output
dropped by just 660MW. Spin up Dinorwig to cater for immediate
frequency support and then pull up the output by just 20 MW a piece
across the other 500/660MW units in around 10 minutes and the
frequency stops more or less bang on 50Hz. An absolute piece of ****.

When the transformers at one location decided it was bonfire night and
a number were totally destroyed by an oil fire - the whole substation
was remotely isolated, the effects other than in the immediate
vicinity were minimal. At another location when switchgear decided to
partly operate followed immediately by catastrophic explosion, the
backup capacity and reconfigurability meant the load to customers
returned within 45 minutes. Parts of the substation was reminiscent
of a B52 bomb strike, huge bits of shapnel flew hundreds of metres and
embedded themselves into walls and trees, some parts were never found.

When a mobile crane driver left his jib up and shorted out the
overhead lines at Hartlepool, exploding all his tyres, blowing a hole
30 feet across and 10 feet deep in the tarmac, the generation of
1320MW was lost, Dinorwig came online from zero output in just over a
minute - they were manually instructed from grid control on them
seeing falling grid frequency, from indication of the overhead line
circuit failing and from loss of generation. No lights went out
although the crane driver saw his life flash before him. If you were
in earshot you might have heard a bang, if you were watching telly
with the sound turned up you wouldn't have noticed a thing.

Even with the grid system completely split north/south in the
"hurricane" of 1987, with multiple repeated double circuit line faults
AND two almost simultaneous double circuit line faults the power
system survived and kept most of the lights on. Some switchgear was
operated more times in one day than in 10 years of normal operation.
The output from Dinorwig was up and down faster than a whore's
knickers. Yes you might have had no lights or standing trees in leafy
Surrey, but the rest of the country went to work as normal.

So, no "Direct line to every power station in the country" but 20
years of operational experience says that the current operating regime
is correct.



Yep. One more reason why the GRID should be NATIONALISED again.

US experience is the reverse..no redundancy, no spare capacity and no
incentive to 'keep the lights on all the time' just and incentive to do
it all as cheap as possible.

NOTE: I am in prnciple a rabid advocate of privatisation, for everything
that is *not* a de facto national monopoly. Road, rail and electrical
networks are IMHO just that.

"Owain" wrote in message
...
Mary Fisher wrote:
I have to say I am very impressed with the French electricity. It's not
only cheaper but more reliable.
Oh! That's not what a grandson said when he visited us last week. He
lives somewhere near Limoges and said it was great to be back in England
even for a short time because of the reliable power.
Perhaps it's different by area - as it seems to be here.

Perhaps they export their best electricity, like their wine, leaving the
locals with the rough peasant stuff.

:-)

This same callow youth (you don't hear that oftn these days!) denied that we
got the best wine, he said that French table wines are very cheap and
"superb".

I take everything he says with a pinch of salt :-)

Lovely lad, he'll grow up.

Mary

Owain

On 06 Oct 2006 20:39:57 GMT, Adrian wrote:

Guy King ) gurgled happily, sounding much like they
were saying :


But then I thought the Allegro estate was a nice looking car.

Friend of mine styled the rear end of that...

Isn't that the car that had better aerodynamics going backwards
rather than forwards?

--
Peter Parry.
http://www.wpp.ltd.uk/

In message , Peter Parry
writes
On 06 Oct 2006 20:39:57 GMT, Adrian wrote:

Guy King ) gurgled happily, sounding much like they
were saying :


But then I thought the Allegro estate was a nice looking car.

Friend of mine styled the rear end of that...

Isn't that the car that had better aerodynamics going backwards
rather than forwards?

An academic question from what I remember

getting one to actually go in either direction was something of an
accomplishment

--
geoff

When the transformers at one location decided it was bonfire night and
a number were totally destroyed by an oil fire - the whole substation
was remotely isolated, the effects other than in the immediate
vicinity were minimal. At another location when switchgear decided to
partly operate followed immediately by catastrophic explosion, the
backup capacity and reconfigurability meant the load to customers
returned within 45 minutes. Parts of the substation was reminiscent
of a B52 bomb strike, huge bits of shapnel flew hundreds of metres and
embedded themselves into walls and trees, some parts were never found.


Ooooh!, I'm definitely not having one of them in my back yard if they
behave like that;-!...

Interesting article 'tho!....
--
Tony Sayer

The message
from raden contains these words:

getting one to actually go in either direction was something of an
accomplishment

I had my Allegro for a couple of years and apart from the occasion when
the starter motor punched its way free of the gearbox housing because
the teeth were so worn they met instead of meshed, it was very reliable.
The only tine it let me down was when I tried to remove the plastic
coolant filler plug when it was too hot and fractured it - the next day
it split on me.

--
Skipweasel
Pay no attention to that man behind the curtain.

"Guy King" wrote in message
...
The message
from raden contains these words:

getting one to actually go in either direction was something of an
accomplishment

I had my Allegro for a couple of years and apart from the occasion when
the starter motor punched its way free of the gearbox housing because
the teeth were so worn they met instead of meshed, it was very reliable.
The only tine it let me down was when I tried to remove the plastic
coolant filler plug when it was too hot and fractured it - the next day
it split on me.

I passed my test in an Allegro but not the estate. I didn't like it then nor
did I when Spouse bought a friend's for £100. It did everything we asked of
it but there was something ... could never put my finger on it. I was glad
when it died and Spouse took notice of me (for once) and agreed not to
repair it.

Perhaps it was the name ...

Mary

--
Skipweasel
Pay no attention to that man behind the curtain.

The message t
from "Mary Fisher" contains these words:

It did everything we asked of
it but there was something ... could never put my finger on it.

I really liked mine. If I could find a good condition 1500 or 1750
estate again I'd have one.

--
Skipweasel
Pay no attention to that man behind the curtain.

On Sat, 7 Oct 2006 22:35:09 +0100, Andy Hall wrote:

If anything Cisco does at least keep products on the market rather
longer than the typical domestic products.

Yeabut this kit is now approaching 5 years old and it wasn't state of the
art, cutting edge, stuff then. B-)

I suppose if you were going to go for a different band/technology,
Alvarion (Breezecom) would be worth a look.

FX: Google WiMAX... not convinced that WiMAX will live up to the hype
there is some WiMAX in the network it works but not up to expectations.
I'll pass it on though. We have one bit of Proxim kit that has basically
been fit and forget, unlike the Cisco stuff that has a (weird) mind of
it's own.

Do any of the providers have LLU equipment in the exchange there?

I guess you've tried the obvious players like Easynet and Pipex?

CLEO are about to have their own DSLAM but when approached about using
ADSL for the backhaul instead of their wireless network the price was the
same! Bar stewards. I doubt very much that there are any other providers
with kit in the exchnage, it only has, at most, 2,000 numbers.

Since you have traffic shaping, couldn't you offer different bandwidths
and contentions and charge accordingly?

We do from £7.99 @ 128kbps to £29.99 @ 512kbps with backup. Unfortunately
we have most customers paying £7.99 not every one is a speed freak or
gamer. Provided that mail arrives and the web isn't too slow people are
happy and £8/month for an always on, full duplex, 128kbps connection is a
real bargin. There are a rather high proportion of low income households
and the company has a social remit...

--
Cheers
Dave. pam is missing e-mail

On 2006-10-08 22:42:26 +0100, "Dave Liquorice" said:

On Sat, 7 Oct 2006 22:35:09 +0100, Andy Hall wrote:

If anything Cisco does at least keep products on the market rather
longer than the typical domestic products.

Yeabut this kit is now approaching 5 years old and it wasn't state of
th e art, cutting edge, stuff then. B-)

Oh well.


I suppose if you were going to go for a different band/technology,
Alvarion (Breezecom) would be worth a look.

FX: Google WiMAX... not convinced that WiMAX will live up to the hype
there is some WiMAX in the network it works but not up to expectations.
I'll pass it on though. We have one bit of Proxim kit that has
basically been fit and forget, unlike the Cisco stuff that has a
(weird) mind of it's own.

Mmm.... not clear where that's going.




Do any of the providers have LLU equipment in the exchange there?

I guess you've tried the obvious players like Easynet and Pipex?

CLEO are about to have their own DSLAM but when approached about using
ADSL for the backhaul instead of their wireless network the price was
th e same! Bar stewards. I doubt very much that there are any other
providers with kit in the exchnage, it only has, at most, 2,000
numbers.

... and of course I guess the next major towns where there might be
something are Carlisle and Newcastle which rules out a few options
because of the connection that would be needed to those.

Is CLEO the present provider?



Since you have traffic shaping, couldn't you offer different bandwidth
s
and contentions and charge accordingly?

We do from £7.99 @ 128kbps to £29.99 @ 512kbps with backup. Unfortun
ately we have most customers paying £7.99 not every one is a speed
freak or
gamer. Provided that mail arrives and the web isn't too slow people are
happy and £8/month for an always on, full duplex, 128kbps connection i
s a real bargin. There are a rather high proportion of low income
households and the company has a social remit...

I was going to say that £8 is way too cheap, but if the available
market and other constraints determine it, it limits the options.
Would covering a larger area help at all, or is the return on
investment likely to make that impractical?