Slashdot Mirror
Should We Fill the Sahara With Solar Panels? (bbc.com)
An anonymous reader writes: A panel of experts at the BBC discuss the possibility of re-purposing the Sahara Desert. Instead of having over 9 million square kilometers of barren sand, we could start a massive project to gradually fill it with solar panels. The remarks are illuminating: "The technology is good. It's matured a lot in the last few years in terms of thermal storage. And the Sahara desert is so big that if there is cloudy weather, it's localized, and with thermal storage, it can provide absolutely reliable power." The difficulties turn out to be mostly political: "The biggest potential pitfall is that it's politically complicated. You're not going to develop solar energy in the Sahara unless you have a very strong state involvement, both on the side of the consumers and the project developers." And one of the panelists points out that Africa must have a large share of the benefits: "Things have changed. Africans are self-confident now, they want to participate in their development, and they want to have part of their resources, they are not just there to always give to the rest of the world and remain poor."
Solar panels don't like sand storms.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
Islamic Solar In Sahara
One of the benefits of switching to renewables is to move the energy source away from muslim controlled countries. This clearly does not have that advantage.
The Sahara has some benefits (right weather, low cost land), but probably has more costs than make it worthwhile. As the article says, there are significant political issues. They will require huge bribes, either directly to the politicians involved or to organizations that 'represent the people' (that don't really). When someone says that Africa must have a large share of the benefits, you know that means that lots of people need to be paid off.
Sadly, it makes more sense to do it someplace with a better political system, better technical infrastructure, and closer to where the power will be used. The overall cost will turn out to be lower.
The more people I meet, the better I like my dog.
It will improve but if you were to put a billion dollars into solar panels, you would see a fifth the amount of solar actually built there which changes the cost/benefit equation substantially.
Plus it becomes a massive target for attacks and blackmail over attacks. You could patrol and militarize the region but that would cost money and change the cost/benefit again.
And... some of the dunes in the sahara are 75 stories tall and they drift around and could cover your facility if left unchecked.
And finally, creating that much shade under the panels would probably change the microclimate. You might see changes under the panels- life taking a foothold in the shade. Not sure what unintended consequenes that might have.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
One big disadvantage of solar power is that it only works some of the time. The intermittent nature of both solar and wind is a serious problem. There's some amount that they help each other out, because in many locations the wind is strongest at night. Because of the intermittent nature of solar power, one cannot have large scale grids be completely solar without a lot of improvements in storage technology. Right now, battery technology is improving but it isn't where it needs to be. The best storage for most purposes right now is pumped hydroelectric https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity where one pumps water high up to a reserve when there is excess and then recovers it using a hydroelectric plant. This is more efficient than batteries. However, it requires specific geology to work well.
The other big issue with this plan is an issue is efficient transmission. If you are putting a large fraction of the entire world's power in one area, you are going to need to have massive transmission lines. Transmission is a major loss of power already. There have been small scale projects to use superconductors for transmission lines which need to be kept very cold but have very high efficiency. Holbrook Substation in Long Island for example has a 600 meter long superconducting line https://en.wikipedia.org/wiki/Holbrook_Superconductor_Project but this is literally multiple orders of magnitude smaller than the distances needed for the proposal,some of which would likely need to go underwater, and there has never been a serious superconducting line run underwater.
I do not see the word “albedo” in this article. This is worrying. A lot of ecologist militant consider solar and wind energy as free energy just there for the taking. This is mostly true, but not entirely true.
Covering a large area of land with solar panels (even assuming they are thermal panels, not too fragile and with not too much fabrication byproducts) would change the albedo of that area, i.e. the proportion of solar light that is reflected by the ground. This will in turn change the climate of the area, and if the area is large enough, change the climate of the whole planet by changing the trade winds. It is entirely possible that in this particular instance the change would be for the good, but it is very hard to predict.
The same applies to large farms of wind turbines: they capture energy from the wind, and therefore weaken prevailing winds. Any large-scale localized change to elements of the climate has very complex consequences.
To get any good out of that much electrical power, you'd need a huge market to sell it to.
Europe wouldn't be it - too far away, across the Mediterranean. The rest of Africa? Maybe once the political landscape settles down. No bets on that one, though.
Sell electricity to the locals? The poor ones? In a region where oil prices are naturally low?
Build a whole bunch of new industries to use it? You're in a chicken-and-the-egg situation there. Nobody would build the factories until the power was ready, and nobody is going to build the solar system until they know they can sell the power. Then, of course, you need to ship raw materials in, and train a whole generation of factory workers from scratch, in a relatively short period.
And, as others have mentioned, solar plants in deserts have the "sand question" to deal with. Beside the whole issue of sandblasted glass, you have to keep them clean, which means, in general, water. Which is in incredibly short supply in the Sahara.
Of course, the authors admit these issues, but handwave it with "state involvement," which means "we need to get governments to pay for this silly thing."
This a good plan; there is no other justifiable purpose for Saskatchewan
The discussion in that article is about a technology that concentrates the solar energy to melt "salt" .this molten "salt" is then used to boil water to drive steam turbines. I know a bit out this. While in theory the water is condensed and resumed, it is the sent to cooling towers. The result of this is the need for a lot of really clean makeup water.
I suspect the lack of water resources in a desert actually makes this recnically I feasible.
At least not yet.
The cost of transmission would be significant. The cost of construction would be non-trivial (get the panels form a nearby port to the site, get enough labor locally, supply chain all of their needs, etc). The reliability risk of putting so many eggs in one basket (both at the site and the transmission across the Mediterranean). And, concentrating the solar in one place results in unnecessarily diurnal production.
Instead, put some panels in the Sahara, sure. But before that, keep putting panels in low-cost locations nearer to load. Rooftops. Sites containing waste (capped landfills, etc) or otherwise economically non-productive and ecologically not interesting. Roadsides. The installation cost per kW will be higher, because of a lack of economies of scale, higher labor cost, and additional equipment necessary. But, you get the value of saving on transmission and distribution construction costs and line losses, the smoothing and stretching of production due to geographic diversity, and both the energy security and the economic boost of doing work in your own country,
Support a few technologists in Washington.
Does the EU even have enough troops to protect something that massive in such an unstable region? Nine million square kilometers and surrounded by notoriously unstable countries with weak governments? Without a WWII-sized massive military force to protect it, every tinpot mercenary leader and dictator will be demanding perpetual extortion not to sabotage it.
SJW's don't eliminate discrimination. They just expropriate it for themselves.
To get any good out of that much electrical power, you'd need a huge market to sell it to.
Europe wouldn't be it - too far away, across the Mediterranean. The rest of Africa? Maybe once the political landscape settles down. No bets on that one, though.
All of non-Scandinavian Europe is within 1500 miles of the Sahara. About 200 million Africans live farther away from the Sahara than that.
And 1500 miles isn't that far. For one thing, we've got plenty of under sea cables spanning distances on the order of the width of the Mediteranean, be it the ~10 miles near Gibraltar or the ~100 miles from Tunisia to Sicily, or even the ~350 miles from Egypt to Turkey. For example, NorNed is a 360 mile undersea cable between Norway and the Netherlands. Of course, there will need to be some firming of transmission infrastructure in Europe if you're dropping that much power at one (or even multiple) locations, but the problem isn't one of distance.
The problems are cost, energy security, and reliability. There are still plenty of low-enough cost locations throughout Europe for Europeans to spend that much money in Northern Africa and be encumbered with the reduction in energy security and reliability. As for Africans south of the Sahara, it's really the same story. The additional production per watt of panel in the Sahara isn't enough to overcome the transmission requirements -- cost, security, and and reliability.
Support a few technologists in Washington.
And why not wind too? They aren't mutually exclusive. It would provide some power at night time. I believe the Sahara is a pretty breezy place. Am I wrong?
No, you are not - in a general sense, though. There are many places in the Sahara with wind during the night (not to speak about daytime). The problem is knowing exactly where the strongest winds blow during the night. Remember, the Sahara is a more than vast place. Note: I have traveled the Sahara extensively: Morocco, Mauritania, Chad, Egypt. Egypt - the "eastern desert", between the Nile and the Red Sea - had the weakest winds during the night, Mauritania the strongest, and, more important: the most reliably blowing night winds.
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
LOL
I gulped wine over the table upon reading this. Mod parent up !
Religous speak to God. Insane are spoken to by God. When all shut up, one can finally hear Shostakovich in peace
http://www.desertec.org/ They tried to launch an initiative to build solar power in north Africa. However, they did not succeed so far. https://en.wikipedia.org/wiki/...
If you're going to build a massive solar installation, it makes sense to start with somewhere like nevada or arizona - politically stable, infrastructure already in place and plenty of nearby demand.
http://spamdecoy.net - free throwaway anonymous email - avoid spam!
Solar panels don't like sand storms.
Sandblasting mirrors is bad too.
Actually, sand blasting is much worse for mirrors than for flat-plate photovoltaic panels. Sandblasting the surface of a photovoltaic panel had very little effect-- it roughens the surface, but roughened glass still lets light through. Roughened mirrors, however, while they still reflect light, reflect it diffusely, which is useless for concentrating sunlight.
Dust is a more of a problem, because it sticks, but there again, it's worse for concentrating systems than for flat plate panels, since much of the scattering by dust particles is forward scattering.
http://www.geoffreylandis.com
It's coarse and irritating and it gets everywhere.
If the question is "should Western governments spend massive amounts of money to put solar panels in the Sahara desert", the answer is "no".
When it becomes economically feasible to do so (taking into account political risks and transportation costs), investors will start doing so.
The only reason for Western governments to do this is because Western militaries could (and would) implicitly subsidize the necessary security arrangements. "Subsidize" here means that once our government had built massive solar farms there and we were energy depend on it, our military would do and spend whatever it takes to defend them.
Was colonialism really bad? People were safer and more wealthy under colonial rule then modern mob rule. Look at crime in South Africa for example.
I love Jesus, except for his foreign policy.
Exactly. All of these people promoting examples of socialism are examples of capitalist economies that are so rich that they are able to provide for a welfare state. If you tried a welfare state in Africa it wouldn't work because there is nothing to redistribute.
I love Jesus, except for his foreign policy.