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Concentrating Solar Power EDM 123
16 December, 2008 - 14:29
PLEASE CIRCULATE THIS MESSAGE WIDELY
PLEASE ASK YOUR MP TO SIGN EDM 123 (It should only take a few minutes -- see below)
Dr Howard Stoate MP has very kindly posted Early Day Motion 123 08-09 in support of the DESERTEC concept ("Concentrating solar power and the creation of a high voltage direct current supergrid"). Many thanks to Dr Stoate for his support. (For full EDM, see http://edmi.parliament.uk/EDMi/EDMDetails.aspx?EDMID=37115&SESSION=899 ).
The DESERTEC concept is probably the single most effective means of cutting worldwide emissions of CO2. The worldwide potential of the DESERTEC concept is so large that, on its own, it could provide all seven of Stephen Pacala and Robert Socolow’s "stabilisation wedges" , and more.
Information about the DESERTEC concept may be found on www.trec-uk.org.uk and www.desertec.org . Endorsements of the concept by high-profile organisations and individuals may be found on www.trec-uk.org.uk/endorsements.html .
It would be good if as many people as possible would write to their MPs, asking them to sign the EDM.
To make this as painless as possible, an example letter has been provided, with a link to the free WriteToThem service, on this page: www.trec-uk.org.uk/lobby.html#EDM123 .
It should take only a few minutes to write a letter and send it off. If you are a UK citizen, do please write to your MP soon.
Many thanks,
Gerry Wolff
Coordinator of DESERTEC-UK
gerrywolff65@gmail.com, +44 (0)1248 712962, www.trec-uk.org.uk
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6 July, 2009 - 18:02
#2
Thanks Chris for a sound critique. Might I point out the slightly questionable nature of the original posting asking for messages of support to MPs from the coordinator of the company to benefit from the process.
6 July, 2009 - 22:44
#3
Desertec-a lobbying group
Actually, I think you will find, if you did your research, that Desertec, formerly known as TREC, are a lobbying group of volunteers for CSP, much as CCC is a lobbying group. They do not benefit financially.
Most of the objections raised above are dealt with in very significant depth on the Desertec website, http://www.trec-uk.org.uk/, which I suggest you investigate.
In particular, HV-DC is the only technique that will work for the transfer of large amounts of power over undersea cables. It is currently being proposed for the connection of windfarms in Scotland to England, bypassing the onshore national grid. The loss for very high voltage DC is 2% per 1000km, and HV-DC has been used to connect France and the UK for some considerable time.
CSP has been used in California for over 20 years and is currently being deployed in Egypt, Jordan, Spain, Morocco, Algeria, UAE, China, and Australia. The technology is thus tried and tested.
7 July, 2009 - 09:51
#4
CSP issues debunked.
Further to my last posting I am reposting a comment made last year on the old forum, which was not transferred over to the new forum.
-----------------------------
I asked Gerry Wolff, co-ordinator of TREC-UK, to respond to the
queries raised about CSP recently.
His answers to objections raised are:
LOCAL AND DECENTRALISED SOLUTIONS ARE BETTER
There is quite a lot that can be said on this subject. In brief:
Local generation of electricity (with PV, combined heat and power,
micro wind turbines etc) certainly has a role to play. But so do large-
scale but remote sources of renewable energy such as offshore wind
farms, wave farms, tidal stream generators—and CSP. Only time will
show what is the best balance between the two.
There is so much more solar energy available in the Sahara that it
makes good sense to generate electricity there rather than in cloudy
countries further north. Researchers at the German Aerospace Centre
have calculated that solar electricity from the Middle East and North
Africa is likely to become one of the cheapest sources of electricity
in Europe, and that includes the cost of transmitting it.
Quite apart from the transmission of "clean power from deserts", there
are several other benefits from large-scale transmission grids:
They provide access to other large-scale but remote sources of
renewable energy such as offshore wind farms, wave farms, tidal stream
generators etc.
Without the provision of a transmission grid, local decentralised
generation of electricity would be wasteful—because surplus power in
any area cannot be moved to where it may be needed.
Large-scale transmission grids help to smooth our variations in supply
and demand.
And they improve energy security because any shortfall in one area can
usually be met from one or more other areas.
Some people suggest that large-scale generation of electricity and
large-scale transmission grids simply concentrate power into the hands
of a few large energy companies. This has been true in the past and is
still true in some places but there is no need for it to be true in
the future.
The provision of a single market for electricity throughout the EU
(which is favoured by the European Commission and the British
government and is being developed now) should promote competition
between suppliers and between different sources of electricity.
There are good reasons to extend the single market for electricity to
EUMENA ( EU, Middle East and North Africa) and beyond.
There must be appropriate provision to ensure that local,
decentralised generation of electricity can develop properly alongside
other sources of electricity.
TECHNOLOGICAL FIXES WILL NOT GET US OUT OF THE MESS WE ARE IN
Some people say that we should simply learn to use less of everything
and others believe that, in addition, we should return to the simpler
ways of living of the past.
This is a complicated subject and cannot really be dealt with briefly
(see New models for economics and the environment ). Here are a few
points that may be useful.
Yes, we should certainly learn to use less of the things that are
causing damage to the environment (such as fossil fuels and nuclear
power).
But demographers say that the population bomb has already been
detonated. Although fertility rates are falling around the world, the
fact that there are many people of breeding age or younger means that
there is little or nothing that can be done to prevent the world's
population growing to 9 billion or 10 billion by about 2070.
Hopefully, it will then stabilise and then start to decline.
This unprecedented situation means that, even if the world were to use
the same amount of energy as it is using now, per capital use of
energy would shrink dramatically. Unless we decide to do without
electricity altogether there will be a need for large amounts of
electricity and it will have to be clean. DESERTEC means the use of
relatively simple technologies that can meet that need.
In summary, the population explosion will force most of us to use less
of everything whether we like it or not. And, for the same reason,
returning to the ways of living of the past is probably not an option.
ISN'T THIS JUST ANOTHER RAID BY RICH COUNTRIES ON THE POOR?
A possible objection to the DESERTEC proposals is that they are just
another case where rich countries take what they need from poorer
countries leaving little for local people, except pollution.
There are good reasons to think otherwise:
Several of the benefits of CSP are purely local and cannot easily be
exported or expropriated. These include local jobs and earnings
(including earnings from exports), local availability of inexpensive,
pollution-free electricity, desalination of sea water, and the
creation of shaded areas under the solar collectors with several
potential uses including horticulture. These various benefits and
bonuses from CSP are described elsewhere.
Unlike oil, coal or mineral extraction, where there can be substantial
negative impacts on local communities, there is no pollution from the
operation of CSP plants. It is true that the early plants did tend to
use quite a lot of water but this is not really necessary and CSP
plants can be designed to operate with little or no net consumption of
water.
The TREC initiative is a collaboration amongst several different
countries, including countries in the Middle East and North Africa.
There are large potential benefits both for countries in the sunbelt
and other countries that may buy solar electricity from there.
DESERTEC can and should be a win-win collaboration that will be of
benefit to all.
HOW ABOUT LOSSES OF ENERGY DURING TRANSMISSION?
Using high-voltage direct-current (HVDC) transmission lines (a
technology that has been in use for over 50 years), transmission
losses are about 2% per 1000 km, plus AC/DC conversion losses which
are up to 1% for each end of the transmission line. This means that
there would be less than 10% loss of power over the 2000 km between
Morocco and the UK.
HOW DO CSP PLANTS COPE WITH SANDSTORMS?
It seems that sandstorms are not all that frequent but that may vary
from one desert to another. On the Sahara Wind website
(www.saharawind.com) it says "According to our measurement recordings,
sandstorms are fairly rare in occurrence. Winds blowing eastward from
the desert account for less than 5 % of the normal wind regime.
Sandstorms make only one part of this 5%."
With the parabolic trough type of system, it seems that the operators
simply turn the mirrors upside down during a sandstorm. Other CSP
systems may also protect the mirrors in a similar way. If the CSP
plant is a hybrid (with gas firing as a backup) or if it has heat
storage, then electricity generation may continue during the
sandstorm.
CSP plants have been generating electricity successfully in California
since the mid 1980s without significant damage from sandstorms.
Some of the other questions relating to CSP are discussed on pages
that may be reached from http://www.trec-uk.org.uk/csp.htm .
To which I would just add (CP) that where sandstorms are worst, i.e.
in areas of shifting sands, these would not be obvious areas for
locating CSP. There are many areas in the sahara desert classified as
rocky or gravel rather than sandy, and thus do not suffer from
sandstorms. CSP has been operating in deserts in California for over
20 years, demonstrating that sandstorms need not be problematic.
7 July, 2009 - 15:14
#5
OK, point taken. I must do my research before posting and not go just on "gut feelings". Let's look at this one first, from "CSP Today" ie Concentrated Solar Power. http://social.csptoday.com/content/saharas-solar-power-potential-underlined
"Even as the area provides enormous opportunity, the report highlighted that scaling up the technology to produce meaningful quantities of electricity means building sprawling arrays of mirrors and pipes across hundreds of miles of remote terrain — and that will be expensive. Gerry Wolff, an engineer who heads DESERTEC, an international consortium of solar-power scientists, estimates it will cost about $59 billion to begin transmitting Sahara power by 2020."
My point was that one should declare one's connections, not that the project was necessarily unsound. I've always said that desert heat/light should be harvested, it's just I'm not yet convinced about international grids although I realise we use them already to an extent.
Anyway, my research continued and the penny dropped. We're not talking photovoltaics but parabolic mirrors, a very tried and tested methodology. Yeah, they've got one such electricity generator in California but the idea goes way back in time. I was struck by one quote "The cost of collecting now is $65 for energy equivalent to one barrel of oil." Roughly equivalent price then, also. "But likely to come down to $26 in future." So last year's oil price! And we must add on transmission costs to those figures, of course.
It has to be said also that the bulk of the membership of DESERTEC are indeed based in North Africa and the Middle East. [Oil connections I've not checked out]Only two in the UK, in fact, but rather more in Germany and other mainland European countries. My feeling is that the $59 billion investment required to get the show on the road is a tricky one (to work out who should pay it), but the constancy of future supply would be even trickier. We'd need some mighty powerful contracts. Just look at how Russia is controlling oil supply.
When they've run out of oil, or they just cant sell it any more (and how likely is that?) then those with the solar power will use it and if they can sell us the power, they will. In the meantime perhaps we should look far more enthusiastically at the vast array of free energy we have at our doorstep. Then maybe we'll be able to export some ourselves and we won't have to wait for expensive manna from the desert.
7 July, 2009 - 16:07
#6
I've participated to one of their presentation here at the Lse, and all the questions seen posted in the forum reflect the doubts that most of us have raised up at that time.
The point, as someone has already argued, is that every country has already got a lot of potential in terms of renewal energy sources to be realised, therefore I see these other important and incredible "innovations" as an addition to more independent and free countries. More, what I'd love to see more and more in every country it is the liberty and the affordability of each household to produce its own clean energy by solar panels, wind turbines and etc... That would be a great advance in geopolitical, monetary and democratic terms for all the humanity.
Thanks to everyone for the very interesting comments.
7 July, 2009 - 22:42
#7
I see the advantage of HVDC with 500,000 volts a 1000 GW would take 2 million amp so a single undersea cable would be quite big to carry that current with a copper loss of 2% per 1000KM. I suppose the problem has its solution but it would take a huge amount of copper that would need to be armoured to survive the undersea environment. By the way the loss to get from the sahara to britain (about 10,000 Km) would be 1.02^10 = 1.21 or 21 % so you would loose 210 GW on route meaning you would need 1210 GW in the first place (calculation approximate and wrong but not far out).
As far as I understand it the wind in the African desert is always very dusty so the mirrors and collectors would be under continual bombardment with particulate matter travelling with the air and the mirror would become unuseable in a few months. Notice the headgear the tribes who live there wear to reduce the impact of the dust. California is different as the dust is precipitated by the water in the air making it clump. So although the air is fairely dry there is has a lower fine dust count.
You need water for horticulture not shade. The shaded region would not grow anything.
In addition to the mirrors and the plants themselves you would need an infra structure of roads living acommodation with schools, shopping centres, airports, railway and imported water to supply local farms. This would probably take most of the generated electricity and the arabs and local aftricans would relish the opportunity of developing their desert to increase the wealth of the local population. This is a solution for North Africa not Europe.
We need a different solution. But while I think such a scheme looks attractive it may not be practical. Besides it is hilly and mountainous there in places but there are vast dune fields there and they would have to be fixed. It is like being on a hot version of Mars.
I think the beduin would be laughing at us "White man's madness" again!
5 August, 2009 - 08:22
#8
spam
Like mid-eastern oil it could be used by arab states to hold the West to ransom and is also vulnerable and liable to terrorist attack. There are also the transmission losses to take into account and the difficult DC technology (why are they going back to DC?).
As far as I understand it each solar collecter is relatively small compared to the total area needed for collection of the solar energy and uses steam turbines so a large number of these units would have to be built in the remote desert regions causing major supply and transportation costs and maintenance costs would be high too. The mirrors would be rapidly degraded by sandblasting by fine particles carried by the wind making it neccessary to replace them very often. This would increase the cost of the electricity. The sheer numbers of generating plants needed to supply the needed electricity that is projected makes the scheme very difficult to implement and like all state funded projects the cost would escalate during construction making completion unlikely. It would soon become a dinosuar and become obsolete before useful power would be delivered.
There would be major problems maintaining the high tension lines across the thousands of kilometers involved involving huge costs.
Solar energy sounds good but the power is spread out and so large areas of collection are needed for each megawatt of power generated. Lets see, solar energy comes in at about 500 watt heat per square meter so for a megawatt power station 2000 square meters of collector are required that is a 44 meter by 44 meter square if a 500 megawatt station was built a 1 million square meter collector is needed that is 1 Km by 1 Km square. To supply Britain at about 1000 GW we would need 2000 such power stations occupying a square of desert 50 Km by 50 Km. That is about 32 miles x 32 miles. Now the arabian and sahara deserts are not flat so we would have mountains and valleys as well as shifting sands and maintaining the mirrors subjected to sandblasting and buffeting by the wind would be a continuous operation involving thousands of skilled staff and the mirror coating factories and mirror companies. The number of mirrors involved is huge too with each mirror being about 10 meters by 10 meters (100 square meters each) - and that is pushing the technology - we would need 21 million mirrors.
Photocells present similar difficulties but with greater numbers owing to their low efficiency. Steam turbines are more efficient but I would have thought a 10% effeciency at conversion at the generator is realistic making the need for 210 million mirrors occupying 160 Km by 160 Km of desert.
There are of course people who live there and the logistics of supplying water and food, towns and shops and schools for the thousands and thousands of people and their families to staff the project during is construction and operation would be huge....
I think we should dream again....
Mind you as a way of supplying an arab population in a reclaimed desert it sounds more feasable.
Chris of South London