Cycling not related to global warming

[raisethe]

On 20 May, 11:50, Tony Raven <[email protected]> wrote:
> raisethe wrote on 19/05/2007 21:08 +0100:
>
> > On 19 May, 17:55, John Kane <[email protected]> wrote:
> >> Scratch one coal miner, up pops two windmill
> >> mechanics, etc.
>
> > I very much doubt that two men working in the wind generating industry
> > will be able to create anything like as much usable energy as one coal
> > miner. Wind just isn't up to speed yet.
>
> > Tony Raven will surely have a link to prove this or otherwise.
>
> You rang sir?
>
> Probably biased given its source but:
>
> "A study by the American Wind Energy Association based on a
> comprehensive survey of wind plant operators in California showed a
> figure of 460 jobs per TWh/year for operation, support and maintenance.
> Another 88 to 146 jobs can be created in manufacture. Coal fired plants
> only generate 116 jobs per TWh (incl. mining)"
>
> Working Future? Jobs and the Environment, London: Friends of the Earth
> (1995)http://www.foe.co.uk/resource/reports/working_future_jobs.html#resource
>
> --
> Tony
>
> "The most savage controversies are those about matters as to which there
> is no good evidence either way."
> - Bertrand Russell

I thought I could trust you to come up with the goods!

This shows wot I said, that coal mining is considerably more labour
efficient than wind farms.

Over to you Mr Brooke.

 

[raisethe]

In the
> old days it used to be the blue screen of death with Windows >

I've had that twice already this morning. :l(

 

[raisethe]

On 20 May, 12:07, Andy Leighton <[email protected]> wrote:
> > > > > So how many of those huge windmills will it take to provide the
> > current electricity requirement for a city of say 500,000 people? Are
> > we talking about 1,000, 10,000 or 100,000?
>
> Less than all of those. The proposed Scottish Power windfarm(*) to the
> south of Glasgow is 140 turbines which will generate a peak of 322 megawatts
> which is easily enough for 200,000 homes.
>
>

What about when it isn't generating the peak? What percentage of time
is the wind sufficiently powerful to provide for these 200,000 homes?

 

[Tony Raven]

Andy Leighton wrote on 20/05/2007 12:07 +0100:
>
> Less than all of those. The proposed Scottish Power windfarm(*) to the
> south of Glasgow is 140 turbines which will generate a peak of 322 megawatts
> which is easily enough for 200,000 homes.
>
> The Danes figure 160MW is enough for 150,000 homes. Their big offshore
> wind farm has a capacity of nearly 400MW (about that of a nuclear power
> station).
>
> The Germans lead the way with about 20,000 MW of wind capacity. We only
> have about a tenth of that.
>
>
> (*) I don't think it has all been built yet.
>

The Danes have over 5,000 windmills producing a nominal 3.1GW - the
total UK generating capacity is ~75GW for comparison. Their big
offshore farms have 200 windmills generating 420MW nominal. But those
are big turbines and need separations of 0.5-0.75km so take up quite a
bit of area.

In the UK wave energy off Western Scotland is probably a better bet but
whichever way it goes a major problem is the infrastructure to move the
energy around the grid in the UK. There is a particular bottleneck
between Scotland and England if wind and wave power generation is
installed in Scotland where the conditions are optimised.

--
Tony

"The most savage controversies are those about matters as to which there
is no good evidence either way."
- Bertrand Russell

 

[Tim Woodall]

On Sun, 20 May 2007 11:55:55 +0100,
Tony Raven <[email protected]> wrote:
> Tim Woodall wrote on 20/05/2007 11:35 +0100:
>>
>> But no user program should be able to affect the OS. We have hundreds,
>> if not thousands of high end SUN boxes[1]. Every week we see OS crashes
>> due to hardware failure but I cannot think of a time where a running
>> program has brought down the OS. (Obviously our infrastructure is
>> designed so that these crashes should cause no more than a small blip
>> before redundant hardware takes over)
>>
>
> There's a difference between a well controlled environment and a
> domestic environment where anything goes. I'm sure we've all
> experienced a programme that when installed crashed the machine. In the
> old days it used to be the blue screen of death with Windows but these
> days its much better at giving the illusion of continuity while it
> recovers itself. YMMV.
>
I still don't agree. I write code. I run my code with ALL the bugs in
it, even the ones so stupid they never get seen by anybody except me
and I never crash the OS. At work we have anything up to 200 programmers
developing code on a machine. If a program in development had even a
small chance of crashing the OS the machine would be crashing all the
time.

I added the async pppd support to the user mode speedtouch driver. This
is about as low level as you can get without actually being in the
kernel code and even when doing that I never crashed the OS.

I have my own boot/install CD to setup my machines. This was based on
Debian Sarge. Yesterday I spent most of the day migrating it to Etch.
This involved completely reworking the initrd, changing the modules
included, reworking how the CD is detected. The thing was reliably
failing to boot the way I wanted (although it's working now) but the
only kernel panics I got were either because it couldn't find the root
fs or because I was "killing" init. Neither of these can happen once the
OS is booted. But me hacking around trying to get cd drivers and network
drivers loaded never once caused a crash.

I only very recently upgraded all my machines to Etch so my uptime is
currently only 16 days. All bar one of my machines I run headless. I
even upgraded them remotely. Quite frankly I expect my machines NEVER to
crash and when they do, so far, it's invariably been hard disk problems.

I have crashed the OS working on kernel drivers. But in order to do the
stuff that causes the OS to crash I have to become root to install the
driver. I cannot crash my own machines when logged in as me.


Tim.

--
God said, "div D = rho, div B = 0, curl E = - @B/@t, curl H = J + @D/@t,"
and there was light.

http://tjw.hn.org/ http://www.locofungus.btinternet.co.uk/

 

[Tim Woodall]

On Sun, 20 May 2007 12:03:38 +0100,
Tony Raven <[email protected]> wrote:
>
> Meanwhile I can remember the forecasters forecasting a very hot summer
> (over 100C)last year and after that failed to materialise a very hard
> winter in the UK which failed to materialise either.
>
Weather forecasting is not climate prediction. Climate prediction is
that, on average, summers will be warmer than winters and that, on
average, the summers of the second half of the 21st century will be
warmer than those of the first half.

is that 100C a typo? I cannot believe any weather forecaster would
predict that for anywhere in the world. I'm not even sure the worst case
doomsday scenario for global warming will get anywhere like that. We
just aren't close enough to the sun to get a runaway greenhouse effect
like Venus.

Tim.

--
God said, "div D = rho, div B = 0, curl E = - @B/@t, curl H = J + @D/@t,"
and there was light.

http://tjw.hn.org/ http://www.locofungus.btinternet.co.uk/

 

[Tony Raven]

Tim Woodall wrote on 20/05/2007 13:08 +0100:
>
> Weather forecasting is not climate prediction. Climate prediction is
> that, on average, summers will be warmer than winters and that, on
> average, the summers of the second half of the 21st century will be
> warmer than those of the first half.

But the summer and winter did not turn out to be the extremes that were
forecast and yet the medya jump on every element of forecast and reality
as proof of global warming.

>
> is that 100C a typo?

<sheepish grin>
I meant 100F
</sheepish grin>


--
Tony

"The most savage controversies are those about matters as to which there
is no good evidence either way."
- Bertrand Russell

 

[Andy Leighton]

On Sun, 20 May 2007 12:37:35 +0100,
Tony Raven <[email protected]> wrote:
> In the UK wave energy off Western Scotland is probably a better bet but
> whichever way it goes a major problem is the infrastructure to move the
> energy around the grid in the UK. There is a particular bottleneck
> between Scotland and England if wind and wave power generation is
> installed in Scotland where the conditions are optimised.

Oh absolutely. A varied approach all involving wave, wind and hydro
is our best bet. Along with far more community based power generation
and micro-generation where it makes sense.

--
Andy Leighton => [email protected]
"The Lord is my shepherd, but we still lost the sheep dog trials"
- Robert Rankin, _They Came And Ate Us_

 

[raisethe]

On 20 May, 12:37, Tony Raven <[email protected]> wrote:
>> The Danes have over 5,000 windmills producing a nominal 3.1GW - the
> total UK generating capacity is ~75GW for comparison.
>

So we need about 120,000 of these windmills to meet the current UK
electricity requirements?

 

[Andy Leighton]

On 20 May 2007 06:34:28 -0700, raisethe <[email protected]> wrote:
> On 20 May, 12:37, Tony Raven <[email protected]> wrote:
>>> The Danes have over 5,000 windmills producing a nominal 3.1GW - the
>> total UK generating capacity is ~75GW for comparison.
>>
>
> So we need about 120,000 of these windmills to meet the current UK
> electricity requirements?

That is a red herring. No one is suggesting the entire UK generation
should be via wind power.

--
Andy Leighton => [email protected]
"The Lord is my shepherd, but we still lost the sheep dog trials"
- Robert Rankin, _They Came And Ate Us_

 

[raisethe]

On 20 May, 14:41, Andy Leighton <[email protected]> wrote:
> On 20 May 2007 06:34:28 -0700, raisethe <[email protected]> wrote:
>
> > On 20 May, 12:37, Tony Raven <[email protected]> wrote:
> >>> The Danes have over 5,000 windmills producing a nominal 3.1GW - the
> >> total UK generating capacity is ~75GW for comparison.
>
> > So we need about 120,000 of these windmills to meet the current UK
> > electricity requirements?
>
> That is a red herring. No one is suggesting the entire UK generation
> should be via wind power.
>
> --
> Andy Leighton => [email protected]

So one of these large windmills is necessary to meet the current
energy requirement of 500 people?

 

[Andy Leighton]

On 20 May 2007 06:58:54 -0700, raisethe <[email protected]> wrote:
> On 20 May, 14:41, Andy Leighton <[email protected]> wrote:
>> On 20 May 2007 06:34:28 -0700, raisethe <[email protected]> wrote:
>>
>> > On 20 May, 12:37, Tony Raven <[email protected]> wrote:
>> >>> The Danes have over 5,000 windmills producing a nominal 3.1GW - the
>> >> total UK generating capacity is ~75GW for comparison.
>>
>> > So we need about 120,000 of these windmills to meet the current UK
>> > electricity requirements?
>>
>> That is a red herring. No one is suggesting the entire UK generation
>> should be via wind power.
>
> So one of these large windmills is necessary to meet the current
> energy requirement of 500 people?

I'm not sure how you are calculating your figures. Offshore wind-farms
tend to have larger turbines than onshore ones. Modern turbines are
better than the older ones.

As an example the proposed Atlantic Array off Ilfracombe would have 370
turbines and generate 1,500 MW. Which is enough for 1.1 million homes
according to the news reports. Dividing that out you get one turbine
providing enough for nearly 3000 homes.

But then you have to take the load factor in to account (which I doubt
the reportage did). Which will reduce that number somewhat (to about
a third of the original numbers). However people do not have a
consistent energy demand. They need more in the winter. Wind turbines
work closer to the theoretical peak in winter (it is usually windier).
However there will always be days where the turbines are barely ticking
over. So a turbine isn't always going to provide energy 100% of the
time (but that is true of all power generation even coal and nuclear).

The answers to such questions that you ask are not simple. Britain
needs a multi-faceted energy plan and I believe wind can and should
play a large part of that - as should wave power.

--
Andy Leighton => [email protected]
"The Lord is my shepherd, but we still lost the sheep dog trials"
- Robert Rankin, _They Came And Ate Us_

 

[Tony Raven]

Andy Leighton wrote on 20/05/2007 16:47 +0100:
> On 20 May 2007 06:58:54 -0700, raisethe <[email protected]> wrote:
>> On 20 May, 14:41, Andy Leighton <[email protected]> wrote:
>>> On 20 May 2007 06:34:28 -0700, raisethe <[email protected]> wrote:
>>>
>>>> On 20 May, 12:37, Tony Raven <[email protected]> wrote:
>>>>>> The Danes have over 5,000 windmills producing a nominal 3.1GW - the
>>>>> total UK generating capacity is ~75GW for comparison.
>>>> So we need about 120,000 of these windmills to meet the current UK
>>>> electricity requirements?
>>> That is a red herring. No one is suggesting the entire UK generation
>>> should be via wind power.
>> So one of these large windmills is necessary to meet the current
>> energy requirement of 500 people?
>
> I'm not sure how you are calculating your figures. Offshore wind-farms
> tend to have larger turbines than onshore ones. Modern turbines are
> better than the older ones.
>
> As an example the proposed Atlantic Array off Ilfracombe would have 370
> turbines and generate 1,500 MW. Which is enough for 1.1 million homes
> according to the news reports. Dividing that out you get one turbine
> providing enough for nearly 3000 homes.
>

Depends how you calculate it and what wind turbine you use. The
Ilfracombe array will be using the big 4MW turbines with rotors some
100+m diameter. If it powers 1.1m homes they had better have some fancy
load management for when everyone switches on their kettle in the TV
break. Our house runs on a base load of about 500W in the day and more
in the evening (central heating pumps, freezer, fridge etc). As soon as
anything else switches on it climbs rapidly so 1400W each is going to be
marginal and that assumes the wind is blowing reasonably.

Tony



--
Tony

"The most savage controversies are those about matters as to which there
is no good evidence either way."
- Bertrand Russell

 

[Simon Brooke]

in message <[email protected]>, raisethe
('[email protected]') wrote:

> What is an IT shop? Do you mean any organisation which creates
> software (microsoft, oracle etc)?

I meant specifically the IT departments of major corporates.

> Whilst I am on this steep learning curve, can you explain why
> computers are so unreliable (to IT illiterates at least).

We haven't had a server go down here for anything other than power failure
in five years. Even with power failure they don't go down hard, we have a
semi-automated shutdown, and can run for twenty minutes without mains
power. That's six servers, so that's thirty years of uptime. Five years
ago we had a processor fan failure which took a server down. That seems
pretty reliable to me. And our servers aren't special - they're just
no-name PC boxes, one of them ten years old (it serves mail and names and
runs the backup tapes; and if it ain't broke don't fix it).

Hang on, quick check, yes. This machine: http://www.earlytech.com/ is also
a ten year old 186MHz Cyrix 686 box, costing about £500 new. It belongs to
a customer of mine, runs his application, and has done so continuously
since 1997 without any shutdowns except for maintenance.

Ordinary cheap computers are very, very reliable.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/
;; If Python is executable pseudocode,
;; then Perl is executable line noise
-- seen on Slashdot.

 

[Simon Brooke]

in message <[email protected]>, Tim Woodall
('[email protected]') wrote:

> I only very recently upgraded all my machines to Etch so my uptime is
> currently only 16 days. All bar one of my machines I run headless. I
> even upgraded them remotely. Quite frankly I expect my machines NEVER to
> crash and when they do, so far, it's invariably been hard disk problems.

Etch is looking very good on our servers:

simon@cullen:~$ more /etc/issue
Debian GNU/Linux 4.0 \n \l

simon@cullen:~$ uptime
17:32:26 up 64 days, 23:54, 1 user, load average: 0.03, 0.03, 0.03

On the other hand the server which runs my personal stuff - i.e. not paying
customers - is on lenny, and seems just as stable:

simon@parkeri:~$ more /etc/issue
Debian GNU/Linux lenny/sid \n \l

simon@parkeri:~$ uptime
17:41:00 up 64 days, 23:53, 1 user, load average: 0.00, 0.00, 0.00

(No, the clocks aren't wrong - I just got interrupted in the middle of
composing this post)

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

'there are no solutions, only precipitates'

 

[Mark Thompson]

> Are there any techniques you can use when buying hardware and software
> which will minimise the hassle?

Keep the OS patched and up to date, don't look at dodgy websites, don't use
IE, don't read/open spam, install as few programs as possible, have a
firewall, have antivirus, keep back ups of files you wish to keep.

 

[Don Whybrow]

Simon Brooke wrote:
>
> (No, the clocks aren't wrong - I just got interrupted in the middle of
> composing this post)

However Simon, I have noticed that your posts consistently appear after
other posts with a later time. Either they are taking the scenic route,
or your clocks are a little slow.

--
Don Whybrow

Sequi Bonum Non Time

"No man's life, liberty, or property is safe while the
legislature is in session." (Judge Gideon J. Tucker, 1866.)

 

[Jeremy Parker]

"raisethe" <[email protected]> wrote

[snip]
>
> What about when it isn't generating the peak? What percentage of
> time
> is the wind sufficiently powerful to provide for these 200,000
> homes?
>
I understood that the laws about getting power out of windmills are
about the same as for riding a bike into a headwind: power goes up
as the cube of the airspeed.

That means the power would be very spiky

Wind power seems fine for some task that's not time critical, such as
grinding the neighbourhood corn, but a bit sub optimal for a grid
that must operate 24/7 and has essentially no storage capacity.

Who pays for all the hardware involved in the connection? The
windmill owner, or the grid owner?

Jeremy Parker

 

[raisethe]

On 20 May, 20:02, Mark Thompson
<pleasegivegenerously@warmmail*_turn_up_the_heat_to_reply*.com> wrote:
> > Are there any techniques you can use when buying hardware and software
> > which will minimise the hassle?
>
> Keep the OS patched and up to date, don't look at dodgy websites, don't use
> IE, don't read/open spam, install as few programs as possible, have a
> firewall, have antivirus, keep back ups of files you wish to keep.

Yes, I do all that, and periodically defrag and use a couple of
registry cleaners, yet still I get the freeze ups - it took me four
attempts to boot up today. I can't open 3 windows on the internet
without the computer seizing, windows media player doesn't work, my
newish external hard drive doesn't work, the original cdwriter has
long since failed, as has the original monitor, printer and modem.
When I upload pictures from my camera it is hit or miss whether it
works or I lose them forever. I can only play one CD before it seizes
the computer and even then it closes excel for some reason. The rest
of my music is on the broken hard drive so is inaccessible.

So I don't lose much work, but have significant downtime and a lot of
hassle. I think this is not particularly untypical, in fact my
experience is probably quite normal for anyone who does not wish to
change his complete system every year or two and is not an IT guru.

 

[Tony Raven]

raisethe wrote on 20/05/2007 22:06 +0100:
> On 20 May, 20:02, Mark Thompson
> <pleasegivegenerously@warmmail*_turn_up_the_heat_to_reply*.com> wrote:
>>> Are there any techniques you can use when buying hardware and software
>>> which will minimise the hassle?
>> Keep the OS patched and up to date, don't look at dodgy websites, don't use
>> IE, don't read/open spam, install as few programs as possible, have a
>> firewall, have antivirus, keep back ups of files you wish to keep.
>
> Yes, I do all that, and periodically defrag and use a couple of
> registry cleaners, yet still I get the freeze ups - it took me four
> attempts to boot up today. I can't open 3 windows on the internet
> without the computer seizing, windows media player doesn't work, my
> newish external hard drive doesn't work, the original cdwriter has
> long since failed, as has the original monitor, printer and modem.
> When I upload pictures from my camera it is hit or miss whether it
> works or I lose them forever. I can only play one CD before it seizes
> the computer and even then it closes excel for some reason. The rest
> of my music is on the broken hard drive so is inaccessible.
>
> So I don't lose much work, but have significant downtime and a lot of
> hassle. I think this is not particularly untypical, in fact my
> experience is probably quite normal for anyone who does not wish to
> change his complete system every year or two and is not an IT guru.
>

What processor speed and how much memory do you have? Insufficient
memory can really slow things down as the computer has to keep swapping
stuff between memory and a hard disk cache.

--
Tony

"The most savage controversies are those about matters as to which there
is no good evidence either way."
- Bertrand Russell