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This is The Sahara Project my grandfather made up with me:

On the western African coast and its surroundings, where the rocky Sahara desert lies, great fields of solar panels will be placed; they will generate a giant amount of energy. But instead of just providing plain electricity, the energy will be used to do this:

  • boil seawater to get water and salt

  • put iodide into the salt and sell it

  • using the electricity it will break down water to oxygen and hydrogen

  • export hydrogen as a fuel for cars, etc.

  • sell some of the oxygen to whoever wants it, and release the rest into the atmosphere

This project has many advantages:

  • efficiency: hydrogen is easy to store; electricity is not

  • logistics: hydrogen can be transported easily

  • burning hydrogen doesn't produce CO₂ or other bad things, just water

  • some of the distilled water can be distributed over Africa

  • this would create a bunch of working spaces — a few smart people would be needed, and a lot of any people (even those that can't read and write) to clean and maintain the panels and other utilities

  • this would upgrade Africa's political situation — they would have a giant source of money (mostly funded by other states)

  • no emissions

This project would have to have a giant investigation at the start, but would promote the world's economics. Water, fuel, salt and electricity prices would drop, and Russia and the Arabic states would go down. The institution would return to the countries in a couple of years.

Also, this project would make a great jump in technology. New technologies would have to be developed, like in America's moon project - when they started the project, it seemed impossible. But they did it, and some of the inventions from then are used today.

Is such a giant project achievable? I know it will never happen in reality, but that's because if the political situation, but I'm asking about the technical side of this. Is this technically possible?

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    $\begingroup$ Salt extracted from sea water will naturally contain sufficient iodine to sustain health. - Adding iodine to salt is a public health measure intended to support that large portion of the population who use deep-mined salt (popular because much cheaper than other kinds), and do not eat very much seafood (usually because they live far from the sea). $\endgroup$ – A. I. Breveleri Sep 16 '16 at 22:32
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    $\begingroup$ You do know that Water fuel salt and Electricity are all already really cheap $\endgroup$ – sdrawkcabdear Sep 16 '16 at 22:49
  • $\begingroup$ Perhaps using the energy and the available sand to extract silicium would be a more viable option, though I don't know whether it's possible to get all the required chemical ingredients from local sources. $\endgroup$ – Daniel Jour Sep 17 '16 at 5:51
  • $\begingroup$ Please don't undermine the vote system. User vote on answers using Votes - comments are ephemeral, which means comments sole purpose are to ask for clarification or discuss parts of an answer. They can be deleted at any time and should not be used for voting on answers. - If you want to accept the answer which most people like, just accept the answer with the most upvotes. Plus: You should wait at least 48 hours before accepting an answer, since they will get a lot more votes until then. $\endgroup$ – Falco Sep 17 '16 at 7:03
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    $\begingroup$ Adding to what @Falco said, you don't have to accept any answer at all. It's a nice touch to the person who wrote the answer you accept, but it isn't in any way required. If you can't pick one that you found most useful, or can but don't want to make your choice public, then don't accept any answer at all. I have a number of questions of my own here where the "best" answer isn't a single answer, but rather the combination of several or even all answers. In such a case, it makes sense to not accept an answer, and simply let community voting do its thing. $\endgroup$ – a CVn Sep 17 '16 at 7:37
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It is possible and you can start small and scale as you go.

Panels might not be best for that scale, but have the advantage of being self contained and someday might be cheap.

Hydrogen is not easy to store: it is dangerous and difficult. You might make methane instead, using atmospheric carbon as the source.

You big problem is: why isn’t it profitable now? logistics. You produce power have industry that needs power over there. How do you get materials in and products out? Focusing on ambient source materials, you still have to worry about shipping. How do you get the concentrated power out of the desert and in the hands of customers?

Where do the workers live? How do they eat and otherwise have a life?

So besides understanding the amortization of solar equipment cost against cost of power produced, you have to realize that if the panels are cheap and available then factories will install them right next to the need, and won’t need to buy from you. The shipping of any goods produced will need to be with the price.

BTW, I have a 10 kW solar array at home. I run the air conditioner in the Texas sun and still have surplus to sell.

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    $\begingroup$ How is hydrogen dangerous and difficult? Gasoline is way more dangerous to handle. Obviously one must take normal precautions when dealing with pressurized gasses, but hydrogen doesn't stand out particularly. People have lots of experience with that kind of thing. $\endgroup$ – Seeds Sep 16 '16 at 21:22
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    $\begingroup$ At petroleum processing plants, the hydrogen is definitely considered more dangerous than gasoline. For one thing, hydrogen is a gas -- much harder to contain than a liquid. Both have the same auto ignition point (~500 deg F). But because hydrogen is so eager to react, it has to be kept much more isolated. $\endgroup$ – SRM Sep 16 '16 at 22:28
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    $\begingroup$ Hydrogen is stored under pressure (otherwise it takes up to much space), most things cool when they expand, hydrogen is one of the few that heats up. So if you puncture a canister of hydrogen gas it will rush out heat up and self ignite, at least gasoline needs someone else to light it. $\endgroup$ – sdrawkcabdear Sep 16 '16 at 22:31
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    $\begingroup$ en.wikipedia.org/wiki/Hydrogen_safety “highest rating… storage poses unique challenges, etc.” $\endgroup$ – JDługosz Sep 16 '16 at 22:34
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    $\begingroup$ Hydrogen can move right through the pores in metal, and tends to embrittle most metals it comes in contact with. It is not energy dense at all like hydrocarbons, and to be useful needs to be compressed to over 250 atm or cryogenically cooled and stored as a liquid, both choices fraught with difficulty. $\endgroup$ – Thucydides Sep 17 '16 at 4:37
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Go through a few items on your list...but this isn't as feasible as you are hoping.

One item that you've badly missed is weather and maintenance. Desert winds bring sand which has the tendancy to get into every nook and cranny you could imagine (even into your cranny's nook?). Maintaining these solar panels and keeping the dust and sand off them is a rather large ongoing expense you will need to consider.

effectivity: hydrogen is easy to store; electricity is not

Very not true. Hydrogen will need to be compressed if you want to store much (liquid?) and tends to be explosive. There is much danger here.

logistics: hydrogen can be transported easily

Electricity transports pretty readily, hydrogen transport now requires moving physical hydrogen (which can be explosive). Seems better to move the electricity to where it's needed, then use it to create the hydrogen there.

this would upgrade Africa's political situation — they would have a giant source of money (mostly funded by other states)

If history repeats...you'd have warring factions trying to control the new source of money and it'd likely be destroyed in the process.

no emissions

Solar panels are composed of some pretty toxic substances and have limited lifespans. This is what I like to call emission deferral...it's only no emissions because you defer the toxic impact to some future date.

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    $\begingroup$ @RudolfL.Jelínek you should consider that votes for answer itself usually implies agreement with answer and desire to see it accepted $\endgroup$ – Revolver_Ocelot Sep 17 '16 at 7:47
  • $\begingroup$ Hydrogen is not explosive. It burns, so does natural gas. Solar cells can be recycled very well, and efficiently if you have such a huge amount of them. The problem are solely politics. $\endgroup$ – Karl Sep 17 '16 at 8:04
  • $\begingroup$ The actual PV silicon cells have never been known to wear out. Finished panels have protective layers, frames, and electronics. $\endgroup$ – JDługosz Sep 17 '16 at 8:23
  • $\begingroup$ @Rudolf Generally, you accept the answer which you like most. $\endgroup$ – Nic Hartley Sep 17 '16 at 9:35
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    $\begingroup$ @Karl - Highly flammable and quick to ignite = explosive. 2007 hydrogen explosion. Muskingum explosion: en.wikipedia.org/wiki/Muskingum_River_Power_Plant On January 8, 2007, a hydrogen supply truck was making its routine weekly delivery of H2 gas to the station's hydrogen system, when an explosion occurred at 9:20 a.m. The truck driver was killed in the accident, and ten other people were injured. Premature failure of the pressure-relief device's rupture disc was blamed.[4] Seems like explosive there $\endgroup$ – Twelfth Sep 19 '16 at 18:37
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Your economic problems

Most of your exports are hard to export and not very valuable,

  • Water is dirt cheep, the main cost is moving it
  • Salt very cheap fairly heavy
  • Hydrogen is somewhat valuable but dangerous to move (see JDlugosz
    answer)
  • Oxygen is also a bit tricky to move, its a corrosive corrosive flammable gas.
  • Electricity requires you to have electric lines that connect you to a major users, or a ludicrously expensive set of batteries.

You are deliberately putting your self in the Sahara a long way from anyone who is would buy any significant quantities of any of these things.

At first you would have to build hundreds of miles of powerlines to reach cities large enough to use your power. It is very difficult to maintain power lines over long distances in politically unstable counties (the copper wires are stolen) so even if you built the hundreds of miles of power lines there are a number of African Counties that you would not be able to maintain them in, though some you could.

Your shipping costs will probably vastly outweigh the value of your products.

Yes this would employ tons of people but then it would probably collapse due to lack of profit.

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The idea is not new. One of these days something might come from such proposals.

Regarding your specific idea, why separate the purification and electrolysis steps? It might reduce the maintenance of your electrolysis systems, but the power is used less efficiently.

Why not use the (purified) sea water for agriculture and sell the electric power?

Depending to the size of the project, it might make sense to go to southern Europe instead, like this one. There was some political upheaval in recent years, but not nearly as bad as that in Africa.

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There are other things you can do in the Sahara. If you focus on using local materials and keeping costs down then you should... Build solar furnaces to melt the sand into low grade glass. (smelt out oars as well?) build enormous greenhouses that are watered with simple evaporation based systems. Sell dried fruit and veg.

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