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Ty Gwyn



Joined: 22 Sep 2010
Posts: 4562
Location: Lampeter
PostPosted: Fri Jan 17, 14 10:35 pm    Post subject: Reply with quote
    

There`s to much money floating on this for it not to happen,
France is going fracking,Total is coming here,Centrica has bought into it.
We`ve been fracking oil and gas here since the 60`s,in strata that is more prone to leakage than the lower shale seams below the farewell rock,and none to my knowledge of problems.

Mutton



Joined: 09 May 2009
Posts: 1508

PostPosted: Sat Jan 18, 14 9:31 am    Post subject: Reply with quote
    

@Nick - OK, we're cool.

Hairyloon wrote:
Mutton wrote:


Quote:
3. Tidal power as harvested in an estuary - Severn estuary has been comprehensively investigated and the environmental impacts are bad enough that everyone has currently given up on the idea.

Why do they seem to only ever look at doing these things on a monster scale which will obviously cause monster problems?
What is wrong with lots of small projects instead?

Quote:
But - renewable energy is NOT infinite. If you take enough energy out of the wind or the tidal stream, then you change the climate.

Wind energy is effectively infinite as it is driven by the sun.
The tide is driven by the kinetic energy stored in the orbital velocity of the moon... use enough of that and the moon's orbit will slow down, but I think we'd have to use a heck of a lot of it.


Agreed on large projects - I am deeply fed-up with the whole bigger is better attitude. As well as a lot more reduction of usage, to me it would be better to have small, localised generators for further reducing domestic call on the national grid. Industrial use is all set up to need the heavy duty three phase generation and to have it continuously and reliably - so other than some big hydropower would still need power stations.

I agree that the sun is effectively infinite on a human scale. I agree that the sun drives the wind. But because the planet is finite, so is wind. You do not get something for nothing. Each wind turbine turned by the wind takes some kinetic energy out of the wind flow. There was a theoretical study done a few years ago in Germany, reported in New Scientist, which showed that too many turbines would cause climate change by slowing the wind flow round the planet.
As I mentioned earlier, warming downwind of individual turbines, and whole wind farms has already been measured. The devil is in the detail - while renewable looks infinite, it is not.

Another useful for a while renewable is hot rocks - there is, or was, a test plant at Redruth - and work is getting going again. Eden Project is doing, or looking into it at their place (lost track of where they've reached). But from memory, after about 25 years, the rocks have cooled to the point where they no longer heat the water sufficiently for it to make steam to drive the turbines. Not sure if the rock then re-heats eventually and you can come back to the existing bore hole, or whether you have to keep drilling new ones.

Thorium reactors - they were an alternative to uranium based nuclear power but were not progressed, as they do not produce weapons grade nuclear material as well as energy. There is now development under way - far less radioactive waste. Can also be built small so rather than a national grid, you could have a transit van sized generator for each city.

And research is still ongoing onto nuclear fusion reactors but any working reactors are still a long way off.

But above all, we must live within our means on this planet - nothing except the sun is infinite - coal, nuclear material, wood, land space to build solar panels and the materials from which to manufacture them - all finite.

Hairyloon



Joined: 20 Nov 2008
Posts: 15425
Location: Today I are mostly being in Yorkshire.
PostPosted: Sat Jan 18, 14 9:59 am    Post subject: Reply with quote
    

Mutton wrote:
Industrial use is all set up to need the heavy duty three phase generation and to have it continuously and reliably - so other than some big hydropower would still need power stations.

Why not move some of the energy hungry industry out to offshore energy farms?
Then you avoid the problem of getting the energy back on shore, so there is no limit to how far offshore they can be built.

Quote:
Each wind turbine turned by the wind takes some kinetic energy out of the wind flow. There was a theoretical study done a few years ago in Germany, reported in New Scientist, which showed that too many turbines would cause climate change by slowing the wind flow round the planet.
As I mentioned earlier, warming downwind of individual turbines, and whole wind farms has already been measured.

Have you got a link to this research?
The idea is about as convincing as homeopathy: the proportion of the energy we extract from the whole is minute. Unless perhaps they are demonstrating equipment so sensitive that it can measure homeopathic changes, then I suspect it is twaddle put about by the anti wind brigade.

Mutton



Joined: 09 May 2009
Posts: 1508

PostPosted: Sat Jan 18, 14 10:39 am    Post subject: Reply with quote
    

Hairyloon wrote:
Mutton wrote:
Industrial use is all set up to need the heavy duty three phase generation and to have it continuously and reliably - so other than some big hydropower would still need power stations.

Why not move some of the energy hungry industry out to offshore energy farms?
Then you avoid the problem of getting the energy back on shore, so there is no limit to how far offshore they can be built.



Because of the costs of taking the raw materials out there and bringing the finished product back - including the energy costs. Not to mention the capital and energy cost of building plant from scratch and having all the workforce get there.

Hairyloon wrote:
Mutton wrote:
]Each wind turbine turned by the wind takes some kinetic energy out of the wind flow. There was a theoretical study done a few years ago in Germany, reported in New Scientist, which showed that too many turbines would cause climate change by slowing the wind flow round the planet.
As I mentioned earlier, warming downwind of individual turbines, and whole wind farms has already been measured.

Have you got a link to this research?
The idea is about as convincing as homeopathy: the proportion of the energy we extract from the whole is minute. Unless perhaps they are demonstrating equipment so sensitive that it can measure homeopathic changes, then I suspect it is twaddle put about by the anti wind brigade.


It is stuff I read in the last six months, except for the New Scientist modelled article which was several years ago. Last time I looked the down wind measurements from wind farms came up readily on internet searches. I can't remember which specific sites I looked at but they convinced me. Try googling on the search terms. (Sorry in a rush and not got time to go and look for the original sites I read.)

Hairyloon



Joined: 20 Nov 2008
Posts: 15425
Location: Today I are mostly being in Yorkshire.
PostPosted: Sat Jan 18, 14 10:54 am    Post subject: Reply with quote
    

Mutton wrote:
Hairyloon wrote:

Why not move some of the energy hungry industry out to offshore energy farms?
Then you avoid the problem of getting the energy back on shore, so there is no limit to how far offshore they can be built.


Because of the costs of taking the raw materials out there and bringing the finished product back - including the energy costs.

Woodchip is not a high value commodity, yet I understand we are shipping it right across the Atlantic. Recently I was looking at bulk buying waste oil for fuel, and it seems to be cheaper to ship it over from Thailand than to buy it locally...
So the cost of shipping is not a convincing argument.
Quote:
Not to mention the capital and energy cost of building plant from scratch and having all the workforce get there.

I had assumed they would live aboard rather than commute, and a lot of plant can be dismantled and rebuilt. Much of it is already conveniently near to docks.

Quote:
Hairyloon wrote:
Mutton wrote:
]
As I mentioned earlier, warming downwind of individual turbines, and whole wind farms has already been measured.

Have you got a link to this research?...
I suspect it is twaddle put about by the anti wind brigade.

Try googling on the search terms. (Sorry in a rush and not got time to go and look for the original sites I read.)

I am happy to take it on faith that I am right.
If you want to persuade me otherwise, then, at your convenience, please dig out the links.

Mistress Rose



Joined: 21 Jul 2011
Posts: 15539

PostPosted: Sat Jan 18, 14 3:46 pm    Post subject: Reply with quote
    

There has been a hot rocks project going in Southampton since the 1960s and as far as I know it is still there; certainly was just a few years ago.

I agree smaller might be better, there is a tide mill at Eling on Southampton Water that has been grinding grain for several hundred years. The tide fills a pond behind the mill and it is let out slowly. Not super efficient, but low tech therefore low cost and seems to be a positive for wildlife. Others such as the one at Fareham creek a bit further east no longer exist, sadly.

Hairyloon



Joined: 20 Nov 2008
Posts: 15425
Location: Today I are mostly being in Yorkshire.
PostPosted: Sat Jan 18, 14 5:48 pm    Post subject: Reply with quote
    

Mistress Rose wrote:
The tide fills a pond behind the mill and it is let out slowly. Not super efficient...

If you are starting out with a free and effectively unlimited resource, does it actually matter how inefficiently you capture energy from it?

Mistress Rose



Joined: 21 Jul 2011
Posts: 15539

PostPosted: Sun Jan 19, 14 8:40 am    Post subject: Reply with quote
    

Personally I don't think so. The time will change on a daily basis, and while it is reliable, or at least predictable, as it will change between springs and neaps, it is not necessarily going to come at a convenient time for power generation. It can, however be programmed in so that other forms of energy, including unfortunately fossil fuel at present, can make up the shortfall at known times.

Mutton



Joined: 09 May 2009
Posts: 1508

PostPosted: Sun Jan 19, 14 9:42 am    Post subject: Reply with quote
    

@Hairyloon - I was not just talking about money cost, I was also talking energy cost - as in usage. I think it is insane to be importing wood chips and offsets a lot of the point of using renewables. We should be growing locally and using locally.
And I'd better not get started on importing plastic tatt from around the world and how we in the west are exporting energy usage and pollution to China and other such places by buying so much from there.
At present the world is driven by accountancy - a while ago I saw a documentary talking about how a big chain store was having its underwear cut in this country, all the bits transported to Portugal where it was sewn together by cheaper labour and it was all transported back.

So you think about the energy cost of transporting say bauxite to an offshore location for aluminium smelting - that being one of the heavy industrial users of electricity I was referring to earlier. (Further thought - you then have to deal with all the waste products as well.)

And if you have workers living off shore you have to have all their food taken out too.

All of these are energy costs. They may, or may not, be economically viable given it is done with oil rigs, but they are not sustainable or sensible in terms of energy usage.

Hairyloon



Joined: 20 Nov 2008
Posts: 15425
Location: Today I are mostly being in Yorkshire.
PostPosted: Sun Jan 19, 14 11:18 am    Post subject: Reply with quote
    

Mutton wrote:
@Hairyloon - I was not just talking about money cost, I was also talking energy cost...

I know, but energy costs money, so the point still stands.
Quote:
So you think about the energy cost of transporting say bauxite to an offshore location for aluminium smelting...

Pretty much insignificant compared to the cost of the smelting. Or if it is not, then it is high time we started making more use of sailing ships.
Quote:
(Further thought - you then have to deal with all the waste products as well.)

Meh. Dump them at sea, create an artificial reef. Where's the harm?
Quote:
And if you have workers living off shore you have to have all their food taken out too.

Choose workers that like fish... and put a polytunnel on the roof.

Mutton



Joined: 09 May 2009
Posts: 1508

PostPosted: Sun Jan 19, 14 2:40 pm    Post subject: Reply with quote
    

Hairyloon wrote:
Mutton wrote:
@Hairyloon - I was not just talking about money cost, I was also talking energy cost...

I know, but energy costs money, so the point still stands.
Quote:
So you think about the energy cost of transporting say bauxite to an offshore location for aluminium smelting...

Pretty much insignificant compared to the cost of the smelting. Or if it is not, then it is high time we started making more use of sailing ships.
Quote:
(Further thought - you then have to deal with all the waste products as well.)

Meh. Dump them at sea, create an artificial reef. Where's the harm?
Quote:
And if you have workers living off shore you have to have all their food taken out too.

Choose workers that like fish... and put a polytunnel on the roof.


I don't agree about energy costs money so the point still stands - we HAVE to use less energy - we are using far too much at present and must work towards ways of using less. It is all about joined up thinking and I think our discussion has shown the pitfalls and complexities involved in effective reduction of energy usage - everything needs to be calculated. As I said - we are in an accountancy minded world at present - and I think your answer shows that.

In general, I agree about more use of sailing ships - well in theory - but again you'd have to look at the technical details to see if they are really as good as they look. (One of the things about modern society that deeply bugs me - we are FLYING in fresh fruit and FLOWERS from all around the world. The flowers in particular deeply saddens me - how wasteful of the finite resources of this planet is that.)

I'm going to assume that the rest of your answers were not intended to be taken seriously.

Hairyloon



Joined: 20 Nov 2008
Posts: 15425
Location: Today I are mostly being in Yorkshire.
PostPosted: Sun Jan 19, 14 6:20 pm    Post subject: Reply with quote
    

Mutton wrote:
I'm going to assume that the rest of your answers were not intended to be taken seriously.

Reasonably seriously.
The one that was a question does depend very much upon the answer.

Nick



Joined: 02 Nov 2004
Posts: 34535
Location: Hereford
PostPosted: Mon Jan 20, 14 12:41 pm    Post subject: Reply with quote
    

Nick wrote:
Mutton wrote:
You need to distinguish


I don't. I'm not involved at that level.


See, I say that, but then I inspire Oxford BOFFINS. Sea link.

crofter



Joined: 11 Feb 2007
Posts: 2252

PostPosted: Mon Jan 20, 14 1:08 pm    Post subject: Reply with quote
    

Theoretically, you and the boffins are correct. There is a lot of energy there. But as the article admits

Quote:
the harsh environment makes harnessing it a difficult challenge

Nick



Joined: 02 Nov 2004
Posts: 34535
Location: Hereford
PostPosted: Mon Jan 20, 14 1:16 pm    Post subject: Reply with quote
    

Turning liquified dinosaurs into something which makes metal tubes fly around the world is a difficult challenge. We're up to it.

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