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Three Silver Stars
Posted
Personally I've never been a fan of wind power - too unreliable.

However I'm even less of a fan of offshore wind farms than otherwise.

Simply put I cannot see how these structures can be made strong enough to survive some of the pretty horrendous batterings I've seen in my 18 years working in the North Sea Oil Industry.

Well sure they can make them strong enough but at what cost?
 
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One Gold Star
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Put them onshore then and plant them like daisies in the Outer Hebrides. The climatologists are becoming shrill now. I don't think we have the luxury for messing around any more.

Offshore? As for strong enough - No prob. Jacket type base structure made out of grade 50D steel. Take a 100 year storm - 30m high waves. Well 25m then.

It must be blowing somewhere in Europe or is sunny. So we just need power lines all over Europe.
 
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Three Silver Stars
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quote:
Originally posted by realprimate:
Offshore? As for strong enough - No prob. Jacket type base structure made out of grade 50D steel. Take a 100 year storm - 30m high waves. Well 25m then.


Yes sure it's possible but how much does it cost to make them strong enough? We know wind power returns can be very marginal so is worth spending millions on these things and burning mega tonnes of fossil fuel for the power only to find they never break even? isn't that the experience so far?
 
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Three Gold Stars
Picture of Lucibee
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Have any of you lot played Sim City? I think we should go for Microwave power plants - although they do have a habit of exploding unexpectedly after a few decades...



¸,ø¤°`°¤ø,¸ ¸,ø¤°`°¤ø,¸ buzz buzz buzz¸,ø¤°`°¤ø,¸ ¸,ø¤°`°¤ø,¸
 
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Two Gold Stars
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According to Ecotricity, the 85 metre beast near Reading has a max capacity of 2MW and produces 3.5 million units per year (which if my maths is right is 20% of the max capacity). The carbon footprint saved by this amount of energy is 3000 tonnes - no idea whether this is based on average cost, or coal or gas.

An off-shore turbine will produce more electricity (steadier and stronger winds). Googling "offshore wind turbine" finds a few economic cases for wind power (ie. it's perhaps twice the cost of new gas capacity). But a carbon footprint study is hard to find.

So would anybody (Mubbers) like to estimate the carbon footprint of building and siting an off-shore turbine? I had trouble finding concrete's carbon footprint - one site suggests that a tonne of cement requires a tonne of CO2 to create - so if we had a rough rule of thumb that a tonne of concrete produces about a tonne of CO2, how much concrete is required to support, say, 20 85m wind turbines in 20 metres depth of sea?
 
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Four Silver Stars
Picture of mufcdiver
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quote:
It must be blowing somewhere in Europe or is sunny. So we just need power lines all over Europe.

Spread the leukemia around eh! swap one problem for another Roll Eyes
The futures safe in your hands RP
 
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Three Silver Stars
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quote:
Originally posted by Steve_M:

So would anybody (Mubbers) like to estimate the carbon footprint of building and siting an off-shore turbine? I had trouble finding concrete's carbon footprint - one site suggests that a tonne of cement requires a tonne of CO2 to create - so if we had a rough rule of thumb that a tonne of concrete produces about a tonne of CO2, how much concrete is required to support, say, 20 85m wind turbines in 20 metres depth of sea?


I don't have the time. Not just concrete! There's also all the steel, aluminium, and other more exotic materials to factor in. Plus of course the energy expended getting it built and in place.
 
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Four Silver Stars
Posted Hide Post
quote:
Originally posted by Mubbers:
quote:
Originally posted by Steve_M:

So would anybody (Mubbers) like to estimate the carbon footprint of building and siting an off-shore turbine? I had trouble finding concrete's carbon footprint - one site suggests that a tonne of cement requires a tonne of CO2 to create - so if we had a rough rule of thumb that a tonne of concrete produces about a tonne of CO2, how much concrete is required to support, say, 20 85m wind turbines in 20 metres depth of sea?


I don't have the time. Not just concrete! There's also all the steel, aluminium, and other more exotic materials to factor in. Plus of course the energy expended getting it built and in place.


I'll try another approach to getting my view recorded
 
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Four Silver Stars
Posted Hide Post
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Mubbers:
quote:
Originally posted by Steve_M:

So would anybody (Mubbers) like to estimate the carbon footprint of building and siting an off-shore turbine? I had trouble finding concrete's carbon footprint - one site suggests that a tonne of cement requires a tonne of CO2 to create - so if we had a rough rule of thumb that a tonne of concrete produces about a tonne of CO2, how much concrete is required to support, say, 20 85m wind turbines in 20 metres depth of sea?


I don't have the time. Not just concrete! There's also all the steel, aluminium, and other more exotic materials to factor in. Plus of course the energy expended getting it built and in place.


I'll try another approach to getting my view recorded


Here goes ::
 
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Four Silver Stars
Posted Hide Post
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Mubbers:
quote:
Originally posted by Steve_M:

So would anybody (Mubbers) like to estimate the carbon footprint of building and siting an off-shore turbine? I had trouble finding concrete's carbon footprint - one site suggests that a tonne of cement requires a tonne of CO2 to create - so if we had a rough rule of thumb that a tonne of concrete produces about a tonne of CO2, how much concrete is required to support, say, 20 85m wind turbines in 20 metres depth of sea?


I don't have the time. Not just concrete! There's also all the steel, aluminium, and other more exotic materials to factor in. Plus of course the energy expended getting it built and in place.


I'll try another approach to getting my view recorded


Here goes ::


There is a very large energy company in Germany that owns one of the UK's big two. It publishes a wind report in its annual company review. The Renewable Energy Foundation draw attention this report also. Its interesting reading from a company that ought to know what its talking about.

There should be enough there to Google.
 
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Four Silver Stars
Posted Hide Post
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Mubbers:
quote:
Originally posted by Steve_M:

So would anybody (Mubbers) like to estimate the carbon footprint of building and siting an off-shore turbine? I had trouble finding concrete's carbon footprint - one site suggests that a tonne of cement requires a tonne of CO2 to create - so if we had a rough rule of thumb that a tonne of concrete produces about a tonne of CO2, how much concrete is required to support, say, 20 85m wind turbines in 20 metres depth of sea?


I don't have the time. Not just concrete! There's also all the steel, aluminium, and other more exotic materials to factor in. Plus of course the energy expended getting it built and in place.


I'll try another approach to getting my view recorded


Here goes ::


There is a very large energy company in Germany that owns one of the UK's big two. It publishes a wind report in its annual company review. The Renewable Energy Foundation draw attention this report also. Its interesting reading from a company that ought to know what its talking about.

There should be enough there to Google.


Renewable Energy Foundation. The report is WIND REPORT
 
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Four Silver Stars
Posted Hide Post
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Seskinreay:
quote:
Originally posted by Mubbers:
quote:
Originally posted by Steve_M:

So would anybody (Mubbers) like to estimate the carbon footprint of building and siting an off-shore turbine? I had trouble finding concrete's carbon footprint - one site suggests that a tonne of cement requires a tonne of CO2 to create - so if we had a rough rule of thumb that a tonne of concrete produces about a tonne of CO2, how much concrete is required to support, say, 20 85m wind turbines in 20 metres depth of sea?


I don't have the time. Not just concrete! There's also all the steel, aluminium, and other more exotic materials to factor in. Plus of course the energy expended getting it built and in place.


I'll try another approach to getting my view recorded


Here goes ::


There is a very large energy company in Germany that owns one of the UK's big two. It publishes a wind report in its annual company review. The Renewable Energy Foundation draw attention this report also. Its interesting reading from a company that ought to know what its talking about.

There should be enough there to Google.


Renewable Energy Foundation. The report is WIND REPORT


D;ya think I could get a job with Spooks?
 
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Two Gold Stars
Posted Hide Post
quote:
There is a very large energy company in Germany that owns one of the UK's big two. It publishes a wind report in its annual company review. The Renewable Energy Foundation draw attention this report also. Its interesting reading from a company that ought to know what its talking about.


Couldn't find the report, but found some news stories. The complaint seemed to be that the cost of avoiding emitting CO2 was 41-77 euros per tonne for wind power, and that it was cheaper to insulate homes. That seems fair enough, but you can do both. There are improving standards for new build houses (not strong enough in my opinion) and central heating boiler, and there are numerous grants and tax incentives for insulating houses. It's probably hard for the government to do more in this area without the money going to waste.

Another question would be whether UK wind power could be cheaper because we have more consistent winds, and whether costs will fall as more capacity is built. Further, since the report was written, oil prices have shot up, and in 20 years time we're going to be dependent on Russia for much of our energy supply.

So even if the costs are high, you have to be sure that you could have effectively spent the money in other areas, and you have to make a judgement as to the strategic benefits of diversifying the energy supply as well as the benefits of cutting CO2 emissions (assuming you don't use more CO2 building and maintaining the things!).
 
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One Gold Star
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Seskinreay.

It's a portable file format. Google 'eon 2005' (without quotes) and I think you'll get it as the first item.

Best regards, suricat.
 
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Seskinreay.

It's oh so quiet, it's oh so still! Was that link the one that you wanted?


Steve_M.

Did you get the link?

Most curious, suricat.
 
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Mubbers.

quote:

Personally I've never been a fan of wind power - too unreliable.

Me neither. I'd prefer a water wheel. They are much more reliable for continual electrical power generation and put much less stress on a distribution network (that is if you use wind turbines only for electrical power generation).

The big problem for 'wind power' is its intermittent operation. A large power resource is available from this sector, but only if that resource can be harvested in a non-disruptive way as, and when, it becomes available. It certainly seems that adapting existing systems to accept and use wind generated electrical power is very expensive. Perhaps we should forfeit some efficiency, as it would be less expensive to convert that power into another form at the source of generation and a form of power that can be used at our leisure. Hydrogen would be one such form.
quote:

However I'm even less of a fan of offshore wind farms than otherwise.

If used for electrical power generation I agree, but as above, if used to generate other forms of power the energy available is greater and doesn't use land resource.
quote:

Simply put I cannot see how these structures can be made strong enough to survive some of the pretty horrendous batterings I've seen in my 18 years working in the North Sea Oil Industry.

I only expect that the offshore sites are a bit shallower than the platforms that you've worked on. The waves should be a lot smaller at these depths.
quote:

Well sure they can make them strong enough but at what cost?

There is a positive benefit to industry with their manufacture which offsets cost, but as with everything else, what will be the cost of any alternatives. Oil cost is increasing and if carbon tax is levied fairly coal will soon be more expensive.

Best regards, suricat.
 
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Four Silver Stars
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suricat, wave and tidal power looks a good investment too. I like the waterwheel idea though, my town has one of the fastest flowing rivers in England running through it and it is as yet untapped!
 
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Two Gold Stars
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Found the report and scanned through it. Seems the issues are the ability to forecast winds accurately, the fact that winds can speed up and die down rather quickly (such that other capacity needs to be reactive), the fact that the more wind power you have the more backup power you need (which means more unused capacity), and the fact that the grid infrastructure needs to be updated to transfer the electricity and prevent overloads.

Not insurmountable problems, but obviously they add to the costs. Particularly, the fact that the backup capacity has to remain could be an issue because its existence will be an ongoing risk to the economics of the turbines - ie. the need for wind power can be replaced at a stroke if other energy sources become much cheaper, or if the political will to support wind power weakens. Of course, I don't think the latter will happen as the warming world will enforce the will.

Not sure whether this is relevant, but I wonder what impact off-shore wind farms (or wave farms) would have on reducing coastal erosion.
 
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mufcdiver.

Wave power has been a 'bad' investment to date, not a good one at all. The 'nodding donkey' (or was it the bobbing egg) of way back when, has amounted to nothing and it's only the hydraulic 'snake' (or whatever it's called) that looks to have any kind of future.

Constant tidal current turbines may amount to a sizeable power source, even if their maintenance may pose some technical challenges, but good sites for these in the UK are mostly around the Scottish coast, or where the current flows only in one direction. The solar/lunar tidal systems (e.g. The Proposed Severn Barrage) have the drawback of sinusoidal operation with the obligatory compromise of generation only at favourable tide heights (nearly as problematic as wind power generation). These also need heavy investment to build and are better organised by the government.

The water wheel is somewhat smaller in scale and is considered more a 'personal' power supply, but it's usually reliable. There are also some that provide an excess of electrical power that is sold into the National Grid, but they don't supply much to it. Water wheels have done this in the UK for a few years now and I'm surprised that you haven't heard of them (saying that I only know of one myself, but I'm sure there must be more).

Frankly muf, I'm amazed that more people don't generate at least some of their own electricity. It must be due to lack of systems knowledge, house rental 'permission' difficulties and 'planning' problems.

Best regards, suricat.
 
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Steve_M.

Seeing as offshore wind turbines take mechanical energy from the atmosphere I don't see that they'll make much difference to coastal erosion. They are usually 'steel piled' into sand banks, so there may be some erosion of the sand bank (during installation and from operating vibrations) which could, possibly, lead to heavier wave-fall onto the coast. This in turn may lead to some accelerated coastal erosion, but it's necessary to look at each case individually with the survey notes and turbine specs. I doubt that permissions would be given if coastal erosion was a possible hazard.

Offshore 'wave farms' are different beasts. Here, mechanical energy is taken from the pressure wave on the water (on the water because water is not very compressible). Because the device takes energy 'from' the wave, the wave is decreased in amplitude and continues with less force. I don't know of any wave farms, but a large farm placed just offshore may lead to coastal build-up. Large waves during winter would be unlikely to reach the beach for the usual over-winter 'beach-slump' that is usually seen (this only happens where the land used to be the beach many, many, years ago).

I've made no account for 'long-shore drift', or 'wind-blown sand'.

Steve, I'm not actually qualified to say these things, but my interest in alternative technologies, since I can't remember when, and my engineering background says that I'm probably correct. Hope this helps, but if you are unsure please make other checks.

Best regards, suricat.
 
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One Gold Star
Posted Hide Post
quote:
Originally posted by mufcdiver:
quote:
It must be blowing somewhere in Europe or is sunny. So we just need power lines all over Europe.

Spread the leukemia around eh! swap one problem for another Roll Eyes
The futures safe in your hands RP


There appears to be an association but:-

http://info.cancerresearchuk.org/healthyliving/cancercontroversies/powerlines/

"Even if future research shows that EMFs from power lines can cause childhood leukaemia, they are unlikely to be a major cause of this disease. Less than 1% of UK children with leukaemia come from homes with the highest EMF levels."

So a small risk and the benfits of a thermally stabilied planet outweighs the small number of cancer cases.
 
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Now your turn mufdive. Calculate the number of cancer cases from fossil fuels and nuclear power stations.
 
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quote:
Originally posted by Mubbers:
the power only to find they never break even? isn't that the experience so far?


Sounds like the canard that making solar panels uses more energy than they produce. But both of us need som