** The Climate Change Thread **

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roubaixtuesday
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Joined: 18 Aug 2015, 7:05pm

Re: ** The Climate Change Thread **

Postby roubaixtuesday » 4 Sep 2019, 2:04pm

PDQ Mobile wrote:
roubaixtuesday wrote:
PDQ Mobile wrote:True.

And yet France has over 12 Gigawatts of installed capacity.
Twelve times more.

And it's not all in the Alps but a deal of it is river sourced.

http://www.gridwatch.templar.co.uk/france/


The Thames is, I think, the largest flowrate river in the UK. It has a quoted rate of 65m3/s

The Rhone has a flowrate of 1700m3/s

Twenty six times more.

It's simple physics, which comes from the geography.


You must allow for precipitation variables though.
Clearly the Rhone and it's tribtaries are far more favourable but only sometimes.
In deep winter for example the flow will be far under the quoted figure.

It would appear the Tay has the greastest fliw rate in the UK and is probably more favourable in terms of "geography".

It's quoted mean flow in 2008 is stated as " 208.5 CuM/Sec."
Which is not insignificant?

The other biggys are given as :- "The Tay is a convincing winner, compared with the Trent at 98 CuM/Sec the Severn at 69 CuM/Sec and the Thames at 83 CuM/Sec."

If we can't get a bit of leccy out of that lot I reckon we are not being sensible.


I'm not arguing we can't get "a bit of leccy". I'm arguing, with quantification, that
(1) it is insignificant vs overall UK energy demand, and following your earlier challenge
(2) it is far less than the potential in France, due to different geography.

The numbers you quote continue to support both of those points; the flow rates are far less than French rivers, and Scotland is far lower than the Alps.

PDQ Mobile
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Re: ** The Climate Change Thread **

Postby PDQ Mobile » 4 Sep 2019, 2:16pm

Our present installed capacity of 1GW is around a 30th of average demand.
It we doubled it to 2GW it would be a 15th!
I see no reason ( as a layman) why we couldnt acheieve 3GW, after all our pumped storage manages 2.5 GW now.
To some extent Scotland offsets its lower height differences by high rainfall.
There are maximum feasible "head" heights due to engineering considerations.
These are less of a factor in low "head" but high flow river schemes anyway.

The beauty of hydro is it's rapid response and permanence.

roubaixtuesday
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Joined: 18 Aug 2015, 7:05pm

Re: ** The Climate Change Thread **

Postby roubaixtuesday » 4 Sep 2019, 2:41pm

PDQ Mobile wrote:Our present installed capacity of 1GW is around a 30th of average demand.
It we doubled it to 2GW it would be a 15th!
I see no reason ( as a layman) why we couldnt acheieve 3GW, after all our pumped storage manages 2.5 GW now.
To some extent Scotland offsets its lower height differences by high rainfall.
There are maximum feasible "head" heights due to engineering considerations.
These are less of a factor in low "head" but high flow river schemes anyway.

The beauty of hydro is it's rapid response and permanence.


You are quoting instantaneous values for pumped storage. Pumped storage does NOT contribute to overall supply, it rather smooths it out. The 2.5GW pumped storage is irrelevant to hydro potential; Dinorwig for instance can only run for six hours before running out of water.

Then you quote 1/30th of current total demand. Couple of points:
(1) You are quoting for electricity demand, whereas I quoted for total energy consumption from all sources. In a zero carbon future, you need to substitute fossil fuels too.
(2) Even for electricity, your number seems too high, see https://en.wikipedia.org/wiki/Hydroelec ... ed_Kingdom which quotes 1.8%

Next, you say "I see no reason why" we couldn't triple hydro. I gave you a reference which puts the potential as only ~1.5x todays. You're simply making up numbers here.

However you slice and dice this, hydro, even if totally exploited to its absolute maximum extent, can only make a relatively small contribution to UK overall energy demand.

It's worth expanding for sure but it's a bit part rather a game changer.

By comparison, offshore wind has huge potential: 75GW by 2050 quoted here, for instance. Orders of magnitude more than hydro by comparison

https://www.imeche.org/news/news-articl ... -emissions

Stradageek
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Joined: 17 Jan 2011, 1:07pm

Re: ** The Climate Change Thread **

Postby Stradageek » 4 Sep 2019, 5:33pm

roubaixtuesday wrote:
Stradageek wrote:I've read lots on this topic and also recently attended a talk by Mike Berners-Lee who does seem to have his head screwed on.

The most telling statistic I've gleaned is that if we use renewables to power everything and ditch both fossil fuels and nuclear altogether, we will need to reduce our overall energy consumption to about 10% of what it is now. Renewables simply cannot produce more than this even with acres of solar panels and wind farms and tidal schemes etc. etc.

This will take time and most importantly, unpopular legislation. So with a world run by self serving, careerist politicians I see little hope.

Which is sad because well insulated zero carbon houses can be built (but will seriously erode property developers profits). We could cycle and walk almost everywhere - if towns were redesigned to eliminate the need for cars. We could stop buying throw away goods but again we would only really do this in meaningful numbers if they were legislated against.

Somewhat depressing.


A source for this 10% figure would be nice. I don't think it's correct.

The "purist" vision for a zero Carbon Britain is from the rather excellent Centre for Alternative Technology (you may not agree with them, but they do a proper analysis and don't pretend magical solutions exist) on a practical way to go 100% renewables reckon a 60% reduction in overall energy demand is required:

Capture.JPG

It's well worth a read, both summary and full report. https://www.cat.org.uk/info-resources/z ... he-future/

Personally, I'd keep nuclear.

The 10% figure comes from 'Sustainable energy - Without the hot air' by David JC MacKay, available free online https://www.withouthotair.com/download.html) there is a LOT to read.

I too was a fan of nuclear until I read 'Fukushima - The death knell for Nuclear Energy' by Sean McDonagh and assessed the evidence presented against what I know from a lifetime working in engineering/electronic component reliability - you just cannot make reactors safe enough, entropy is against you.

PDQ Mobile
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Re: ** The Climate Change Thread **

Postby PDQ Mobile » 4 Sep 2019, 5:56pm

Roubaix ^^.
I am well aware that pumped storage is not genuine capacity.
I had hoped that my understanding of that was clear.

Of course wind is a fantastic resource for the UK. I am and always have been a big supporter of offshore wind.
The quoted figure is however only when the wind blows, and sometimes it doesn't for days on end.
If one is a Gridwatch checker, as I am, one sees periods where generation is very small.

I still think that a Gigawatt of present installed capacity for hydro is too small given the water resource that exists in the UK.
We have now just over 10 GW of installed wind.

Given the reliability and flexibility of hydro in my personal view we rather under utilize it.
Certainly previous generations used more of it at various sites around the UK.
The Thames had at Sandford (the biggest lock fall on the Thames) a sizable factory using water power. Numerous small mills can be found nationwide, practically all of them in disuse. Tewksbury I mentioned upthread.

Given the high rainfall of much of upland Britain and those old disused structures a single Gigawatt seems pathetically small.
Choices are difficult and there are downsides as mentioned, but hydro is practically carbon neutral.
And water often continues to flow when the wind stops blowing.

roubaixtuesday
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Joined: 18 Aug 2015, 7:05pm

Re: ** The Climate Change Thread **

Postby roubaixtuesday » 4 Sep 2019, 6:03pm

PDQ Mobile wrote:Roubaix ^^.
I am well aware that pumped storage is not genuine capacity.
I had hoped that my understanding of that was clear.

Of course wind is a fantastic resource for the UK. I am and always have been a big supporter of offshore wind.
The quoted figure is however only when the wind blows, and sometimes it doesn't for days on end.
If one is a Gridwatch checker, as I am, one sees periods where generation is very small.

I still think that a Gigawatt of present installed capacity for hydro is too small given the water resource that exists in the UK.
We have now just over 10 GW of installed wind.

Given the reliability and flexibility of hydro in my personal view we rather under utilize it.
Certainly previous generations used more of it at various sites around the UK.
The Thames had at Sandford (the biggest lock fall on the Thames) a sizable factory using water power. Numerous small mills can be found nationwide, practically all of them in disuse. Tewksbury I mentioned upthread.

Given the high rainfall of much of upland Britain and those old disused structures a single Gigawatt seems pathetically small.
Choices are difficult and there are downsides as mentioned, but hydro is practically carbon neutral.
And water often continues to flow when the wind stops blowing.


Again, laudable sentiments, but no quantification beyond "seems pathetically small".

But I think we've done this to death now!

roubaixtuesday
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Joined: 18 Aug 2015, 7:05pm

Re: ** The Climate Change Thread **

Postby roubaixtuesday » 4 Sep 2019, 6:14pm

Stradageek wrote:
roubaixtuesday wrote:
Stradageek wrote:I've read lots on this topic and also recently attended a talk by Mike Berners-Lee who does seem to have his head screwed on.

The most telling statistic I've gleaned is that if we use renewables to power everything and ditch both fossil fuels and nuclear altogether, we will need to reduce our overall energy consumption to about 10% of what it is now. Renewables simply cannot produce more than this even with acres of solar panels and wind farms and tidal schemes etc. etc.

This will take time and most importantly, unpopular legislation. So with a world run by self serving, careerist politicians I see little hope.

Which is sad because well insulated zero carbon houses can be built (but will seriously erode property developers profits). We could cycle and walk almost everywhere - if towns were redesigned to eliminate the need for cars. We could stop buying throw away goods but again we would only really do this in meaningful numbers if they were legislated against.

Somewhat depressing.


A source for this 10% figure would be nice. I don't think it's correct.

The "purist" vision for a zero Carbon Britain is from the rather excellent Centre for Alternative Technology (you may not agree with them, but they do a proper analysis and don't pretend magical solutions exist) on a practical way to go 100% renewables reckon a 60% reduction in overall energy demand is required:

Capture.JPG

It's well worth a read, both summary and full report. https://www.cat.org.uk/info-resources/z ... he-future/

Personally, I'd keep nuclear.

The 10% figure comes from 'Sustainable energy - Without the hot air' by David JC MacKay, available free online https://www.withouthotair.com/download.html) there is a LOT to read.

I too was a fan of nuclear until I read 'Fukushima - The death knell for Nuclear Energy' by Sean McDonagh and assessed the evidence presented against what I know from a lifetime working in engineering/electronic component reliability - you just cannot make reactors safe enough, entropy is against you.


I'm very familiar with "without hot air" and indeed have the hard copy in front of me right now. I don't see the 10% figure, can you be a bit more specific about where it comes from?

PDQ Mobile
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Joined: 2 Aug 2015, 4:40pm

Re: ** The Climate Change Thread **

Postby PDQ Mobile » 4 Sep 2019, 7:23pm

Roubaix.
Done to death I agree.
Time to finish.
But don't forget there were factories on and driven by the Thames before cheap fossil fuels made them unviable.

Psamathe
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Joined: 10 Jan 2014, 8:56pm

Re: ** The Climate Change Thread **

Postby Psamathe » 12 Oct 2019, 10:05am

Just listening to a podcast (BBC) and an amazing fact:
Consumption of internet porn is equivalent to the carbon emissions of Belgium
(http://open.live.bbc.co.uk/mediaselector/6/redir/version/2.0/mediaset/audio-nondrm-download/proto/http/vpid/p07p63rg.mp3 @4:00)

Ian

Oldjohnw
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Joined: 16 Oct 2018, 4:23am
Location: Northumberland

Re: ** The Climate Change Thread **

Postby Oldjohnw » 12 Oct 2019, 3:49pm

Psamathe wrote:Just listening to a podcast (BBC) and an amazing fact:
Consumption of internet porn is equivalent to the carbon emissions of Belgium
(http://open.live.bbc.co.uk/mediaselector/6/redir/version/2.0/mediaset/audio-nondrm-download/proto/http/vpid/p07p63rg.mp3 @4:00)

Ian



Poor Belgium. What a way to be known.
John

Cycling and recycling

Psamathe
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Joined: 10 Jan 2014, 8:56pm

Re: ** The Climate Change Thread **

Postby Psamathe » 6 Nov 2019, 11:59am

Interesting idea and one I'm surprised has not come up before now. It never occurred to me but the report makes me think it really should (given how other aspects of issues facing society have rightly become part of the educational syllabus).
https://www.independent.co.uk/news/world/europe/italy-climate-change-lessons-school-environment-global-warming-children-a9187216.html wrote:Italy becomes first country to make climate change lessons compulsory for all children
...
Education minister Lorenzo Fioramonti has announced all state schools will dedicate almost one hour per week to climate change issues from the start of the next academic year in September.

Traditional subjects, such as geography, mathematics and physics, will also be studied from the perspective of sustainable development, said the former university economics professor.

Ian

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al_yrpal
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Re: ** The Climate Change Thread **

Postby al_yrpal » 6 Nov 2019, 12:31pm

Thats a great idea. What should you personally do in your home country and what should be done in other countries? The latter being the thing thats so often forgotten or ignored. The Delhi smog and the destruction of the SE Asian rainforest cause huge problems and multiple deaths on a massive scale. This raises political dillemas which everyone should be made aware of.

Al
Touring on a bicycle is a great way to explore and appreciate the countryside and towns you pass through. What do you do to make a difference?