On a smaller scale, putting solar panels in the Sahara Desert and run a big cable to Europe is frequently considered. Being in a desert removes most cloud cover, it's close to Europe, and the area required is miniscule even if you want to provide the entire area of Europe that way.
The only problems are that the day-night cycle still exists and storage is expensive, that it would be a massive capital investment, and that the governments of most countries in the Sahara aren't very stable.
I do not know, whether this is true, but: When I was in school, we learned in geography class, that one could power the whole EU, if we occupied some area of the Sahara desert with solar panels, at least when looking at raw energy output, disregarding day night differences and possibly hot and cold environment that a desert is.
I guess humanity is still not ready for such projects of enormous cooperation between countries, or, that there are too many things in the way, like said temperature rise at day and fall at night, the vast distance the energy would need to be transported (is that a problem?) and maintenance work somewhere in the desert. One can still hope, that some day we will be able to think globally and solve problems that way.
One of the difficult problems with extremely large solar projects is the infrastructure to move the power. In a lot of these cases, the space to build solar is large areas of land that no one uses... which means that there's not much infrastructure to build the solar power plants, and then not much infrastructure to move that power back to places where people live.
Yes, there's a lot of land that could be used for solar. Moving the enough power to power all of Spain (or all of Europe) based on solar requires some very impressive transmission lines.
I would be curious to know why no one has ever tried to put large solar power plants in the Sahara desert. Covering large parts of uninhabited land with photovoltaic arrays and transporting the electricity to Europe via power lines and submarine cables seems to me easier than launch massive solar arrays into space and beam down the power. I know that many countries in that area are politically unstable, but I guess it is possible to find at least one of them whose government is able to guarantee the security of the power plants upon payment of royalties.
>We could provide the world's total energy needs by covering a small portion of the Sahara desert with solar.
The Sahara desert is extremely sandy, and extremely windy, which makes it a pretty terrible, or at least prohibitively-expensive place to build a solar farm.
It is also extremely complicated and extremely expensive to transmit large amounts of power over long distances, particularly across national borders (everyone's on a different AC standard), particularly across many national borders.
I've lived in many places (Seattle, Edinburgh) where a solar panel is only useful about 25% of the year due to clouds, or the simple fact of being so far north. We don't all live in Southern California.
The Sahara presents an environment with lots of sunlight, little clouds, and nothing else being developed there. And it doesn't need to be solar panels- solar farms based on collectors reflecting to a central tower are what is being cited in the article. We can't do that in most developed areas, because it takes up a lot of space- deserts are mostly empty, perfect for that.
In short, it would make far more economic sense to build solar panels in the Sahara and lose 50% of the power to transmission loss piping it all to Scotland than it ever would to put the same solar infrastructure into Edinburgh (or many other cities in the world).
A high voltage DC line should have less losses than the energy gained by moving south. Furthermore, one can pretty much rely on the Sahara sky not being clouded, which is probably more important as you then can rely on having the same energy output every day. The let-down is that it would cost billions to put the necessary lines in place. Putting the solar farms into the south of Spain is likely to be more cost-effective. The nice thing about photovoltaics though is, that there is no minimum size for a plant. This means, we could do both in parallel - extend European solar plants and set up some in Africa.
That's along the lines of one of the bigger proposals I've seen - to cover large inhospitable and hot places like the Sahara. It doesn't have to be with expensive photovoltaic panels, you can take Spain's route and use the mirrors-heating-molten-salt technology instead.
In the short term I'm sure they will install a lot of Chinese solar panels. But longer term it would be cool to build one or more massive solar plants in the Sahara to supply Europe and nearby countries via high voltage cables. You might also be able to re green the land in the shade under them. Just covering half of Niger with panels could potentially power the world.
You can't just put all solar panels in Sahara because of so many more important reasons, mainly energy transportation. Power lines will never be that efficient, and battery storage would be prohibitively expensive (and I am not even sure there would be enough rare metals on earth to build that many batteries).
We worked hand in hand with middle east dictators for centuries now, to get their oil. Oil is interesting because it is cheap to transport (pipelines).
if not for the problem of mitigating sand erosion, deserts seem well-suited for solar farms. I believe the statistic is that all the necessary power to power double humanity's electric consumption could be generated from a tiny patch of the Sahara---big enough to be seen from space, but tiny in the grand scheme of things (1)
(1) This is, of course, the foolish way to go about it, since distribution costs would be enormous and that kind of centralization is dangerous for a robust system. But it's a fun thought experiment to visualize the scale of the problem and the gap between the inefficiency of the modern system and potential improvements.
There are a few things that aren't quite right here.. Primarily that Europe and the Sahara have equal sunlight availability.
The Moroccan plant is in Ouarzazate, which has an average annual irradiance of ~2,200 kWh/sq. meter.[1] Southern Spain is the sunniest part of Europe and the best locations there are closer to 1,800 kWh/sq. meter.[2] That's over 20% more solar energy in Morocco.
The other bit that's not really accurate is about Transmission losses. It's about 400 miles from Ouarzazate to Gilbatrar. Modern HVDC lines have losses of ~3.5% over 1,000km, so call it 3% for this project.[3] That's extremely reasonable for an energy project.
The sun is shining 24 hours a day ... it never stops shining. One could imagine big solar farms in space where there is no shadow or a global energy network if political issues are solved. The EU is already considering building huge solar farms in the Sahara desert, not exactly a stable region right now, but eventually just a tiny bit of desert will be enough for the whole continents energy needs.
Sorry I worded that sentence poorly. Let's assume two scenarios:
a) We create a 200 square mile solar field in the Sahara, from which cables run to Europe to supply electricity. To take this plant out, one just cuts the cables. There, you just plunged Europe into darkness.
b) We create a 20x 10 square mile solar fields in the Sahara, all dispersed over a very large area. Well, this is an engineering and construction project on the scale that dwarfs even the previous project. It is truly vast. Nevermind all the political issues again.
The only problems are that the day-night cycle still exists and storage is expensive, that it would be a massive capital investment, and that the governments of most countries in the Sahara aren't very stable.
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