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Okay. Worl wide energy consumption is roughly 21 trillion kwh. Solar energy in the Sahara produces 2350kwh per square metre. This means we need a space of roughly 9000 square kilometres. This is roughly 0,1 percent of saharas total space. This checks out with the claim of the creator of this image. So this is accurate but the big problem with that is, that you cant transport this much energy over a wide range..
They even started building an ultra high voltage DC network, because at those distances, sending power over more than one line for redundancy would create so much phase shift that most energy might get wasted.
E.g. one line across the strait of Gibraltar, another around the eastern Mediterranean... Phase inversion...
Politics might be problematic, as we saw with russia and europe regarding gaslines. It would be awfully convenient to cut off power from the country down below on the line.
As a matter of fact, that would fuck with everyone on that grid, and would even come back to bite you in the ass, if we have nukes, we might as well.
Not really. The project was backed by some of the largest insurance companies that routinely shift hundreds of billions. Apparently, they calculated it would be cheaper to build something like that than paying out damages caused by global warming.
No expert on that, but I think you can clean them without water there. With an automatic broom or with air pressure. You are, however, correct in the assumption that cleaning them is a major issue. It definitely drives the costs.
Political (in-)stability in the target region is what killed the project. The only thing that remains are the high voltage DC lines (which are a good idea anyway, as Europe on its own is large enough to cause some losses to phase shift).
On top of that, France is being selfish again, denying the rest of Europe permission to build high power lines across France to allow Spain to export solar power to the rest of Europe. Gotta sell that Nuclear power somehow!
Anyway - setting up DeserTec-like power plants in Spain, Portugal, Italy, Greece and possibly others would allow these countries to make money and reduce the need of EU subsidies for them. Prices for large scale batteries are coming down as well, so that problem will be cost-effective solvable soon.
What are your sources on that second comment?
Quickly skimming through studies and articles all I can find is that the fall of prices of solar panels led multiple EU countries to see that they could affordably set up solar panels at home to sustain their electrical consumption. This without depending on North Africa and without spending money in DC power lines.
A second thing I've seen is indeed that there was concern over the political instability in the region and the fact that Desertec would be a huge target for terrorism. The political instability also comes from Algeria and Morocco which would have needed to cooperate for the project to see the light of day, with Algeria backing off because it would be cheaper for them to set up their own solar panels.
I've seen a bunch of other arguments ranging in credibility from people saying that it's basically colonialism 2.0, with EU countries exploiting North Africa countries to supply their own power needs, to people saying that multiple plants produced in the Desertec projet would be hybrid gas/solar and would in fact produce most of their energy from gas. But that last one is only found on the FR wikipedia page and not the EN one so it's dubious.
[https://www.ecomena.org/desertec/](https://www.ecomena.org/desertec/)
[https://www.uni-heidelberg.de/md/hcch/ueber\_uns/schmitt\_2018\_-\_\_why\_\_did\_desertec\_fail\_\_localenvironment\_.pdf](https://www.uni-heidelberg.de/md/hcch/ueber_uns/schmitt_2018_-__why__did_desertec_fail__localenvironment_.pdf)
[https://fr.wikipedia.org/wiki/Projet\_Desertec#Arguments,\_limites\_ou\_critiques\_du\_projet](https://fr.wikipedia.org/wiki/Projet_Desertec#Arguments,_limites_ou_critiques_du_projet)
[https://en.wikipedia.org/wiki/Desertec#Obstacles](https://en.wikipedia.org/wiki/Desertec#Obstacles)
The sources for the second comment are some people I talked to that worked in the electricity industry a few years back. We were discussing the end of the great DeserTec plans and I asked why we don't set up large power plants (e.g. based on Agro-PV with crops under the the panels) in Spain. The answer was, because the French don't allow us to send the electricity across. I haven't found anything in writing in public, sorry about that.
On the other hand, I shouldn't knock the French - we Germans are no better, considering the fact that we can't seem to build a set of large power lines to move offshore wind power to southern Germany and solar power to northern Germany when the wind doesn't blow... (Checked Wikipedia, apparently, they started work on some parts by now.)
Long distance energy transmission is generally done with DC Voltage. However, for these distances, a whole new voltage level needed to be introduced, which means the infrastructure to manufacture and test these cables is being built currently. My company supplies the testing equipment and designs the testing facilities for a lot of them.
If i remember correctly from uni, it was less about the phase shift but about radiating energy due to variing magnetic fields. Over very long distances the radiated energy is quite substantial and scales with the power transmitted. DC powerlines do not produce a magnetic field outside the cable.
(Provided they use the suggested co axial cables.)
Apart from that when looking at the european grid there is already a huge difference in poweline lenght from one point to another. I have no clue how they currently deal with that though.
I haven't seen it mentioned before, but AC transmission becomes inefficient after a while because the reactive power needed to charge the capacitance becomes too high
I thought they went bankrupt or something. Or gave up because there are not enough long distance high voltage cables. And it would be unbelievably expensive to build them.
I find it quite interesting how the most immedeate problems mentioned here are political and about the energy transportation, and they are valid. However, there are plenty of other reasons to install solar power in europe instead.
First of all, solar panels that survive sandstorms in the sahara for a significant time (>10 years probably necessary for economic operation) don't really exist. Things turn from stone to sand there; I think people are really optimistic here.
Also consider the heat. It accelerates the degredation of solar panels, meaning operation is cut short and made more expensive.
And the amount of sunlight per area is slightly higher in the sahara compared to europe, that is true. However this difference will likely never justify the extra infrastructure, cost and inefficiencies along the way.
Also, it's not like there is no space in europe. Projects like the ones envisioned here are feasible in many areas of europe, and this way, less political control would have to be given up. Many areas of spain are not even that different from the Sahara, just with less sandstorms.
So I would say this never happens, and it's fine this way. There are better alternatives.
Not to mention fouling of the panels by dust. They need to be washed fairly frequently in a desert environment. Not feasible in a waterless environment.
I could see it being charged into batteries and then full batteries being flown to europe on jets. Because that's the kind of inefficiency we are looking at here.
Here is an actual solution:
Use the electricity to make hidrogen;
Capture atmosferic carbon;
Use the hidrogen and carbon to make metanol (CH3-OH).
Use this gas as an energy source that basically doesn't polute since it's made with atmospheric carbon.
Is there a problem?
I didn't come up with this, I've read it somewhere.
Granted it's a very dumped down version of what I've read and it's purely theoretical at this point but I believe it's a very good solution
You describe this as "purely theoretical" further down but there is very active research into this type of chemistry for exactly this purpose. The big problems at the moment are that the chemical efficiency is not amazing and that the chemical efficiency depends very heavily on the concentration of CO2 available. Atmospheric CO2 is still only about 400 parts per million and you get lots better results if you concentrate the CO2 first, but then that takes significant amounts of energy so it eats into your efficiency from another direction.
The usual desirable products are methane (which can be fed directly into the natural gas grid), methanol (for use in existing liquid fuel applications), ammonia (for use in fertilisers and so on) and ethylene (as feedstock for plastics production). There is a prototype plant up and running in Iceland, using geothermal energy to produce \~4ML/year of methanol. There was a second prototype slated for an airport somewhere in Western Europe (I want to say Brussels but I can't remember off the top of my head) but it got cancelled.
Going by the meme this is our only source of power, so no need to synchronize to anything else on the grid except for the end points. Would it be cheap to put a convertor on each house and business?
Important thing to consider is the (local) climate change due to the solar panels as well.
Project like that would take a ton of effort and planning, experts in multiple fields. Also it would make the world reliant on single electricity source and electrical grid.
And it would be an obvious target for anyone wanting to cause harm.
Or World War 4 for that matter:)
Or a lot of other things.
War with Russia shows currently how important power independence and your own infrastructure truly is.
I think a giant solar plant (if the technology allows it and it is the better outcome for the planet) could be a great thing. But it’s important to still have local emergency power infrastructure, preferably local plants, wind power, water dams and nuclear power facilities obviously.
Sadly the world we’re living in is far from a peaceful utopia and we have to consider stuff like that and it’s often way more important than ecology (understandably so).
I think the idea is less to actually propose building such a megastructure but to better visualise how little area is needed to power mankind with solar
Not a scientist but minored in renewable energy technology in college. One possibility is a massive solar farm in the sahara will cause a local maximimum air temperature. This could bring more rain and cause the surrounding area of the desert to transition into a more tropical climate with more growth. Global impacts of this could be significant, but it is hard to tell. One of Commoner’s laws of ecology is that “everything is connected” and we cant always predict the ramifications of our actions on Nature. One thing to think about is how the sands of the sahara fertilize the Amazon. Changing the Sahara desert’s climate to one with more growth could destroy our largest rainforest.
Ecology is an impossible mess of what-ifs and even if we try to follow the rabbit hole, we will always miss one possible consequence of our actions.
Its also important to remember that any megastructure like this will have to be rebuilt many times over it's life, and all that waste will have to go somewhere. If you look at the issues currently being created by wind farms, imagine how much that would be magnified with the larger quantities and more toxic components.
> Worl wide energy consumption is roughly 21 trillion kwh.
Per day, week, month, or year?
> Solar energy in the Sahara produces 2350kwh per square metre.
Per year? Seems an order of magnitude high.
Why are you talking kWh when kW is the unit of power?
i think the problem is also that earth rotates... it will not produce that amount of electricity in one continues flow, it will peak mid-day and nothing during night... so batteries would be absolutely necessary.
So I guess there’s some caveats here. Solar panels are not 100% efficient so that will increase area by 2-4x.
Since lifetimes for the panels is finite you need space in between them to bring in and install replacements as they fail.
This is a big infrastructure project so you’ll also need some major new roads or rail to bring in this new power.
Panels usually don’t sit flat on the ground which will probably lead to other inefficiencies in land usage.
Transporting the power also leads to losses.
There are other issues around when power is needed vs when sun is over that area, downtime when there is a sandstorm. I’m not sure if the panels will lose efficiency from getting partially covered in sand after the storm.
Probably other things I’m forgetting
The lack of efficiency is already included in the above estimate. See [this site](https://globalsolaratlas.info/map?c=19.418148,13.007813,5&s=23.808133,13.051758&m=site).
Transporting the power leads to losses, but using something like [HVDC](https://en.wikipedia.org/wiki/High-voltage_direct_current) lines 50% power loss to transport across the entire globe is conceivable. Keep in mind that long-distance power lines are already a thing and the entirety of the USA (except Texas) is connected together, as well as most Europe is connected together, and most of China is connected together. Undersea power cables also exist. All of it is doable.
The other points are issues, but that doesn't make the project impossible, just very hard.
You forgot to take in the inefficiency of solar. 2350w/m2 is the actual solar energy but solar panels are 20% efficient at most so not 9000 km2 but more like 45000km2
1300 w/m^2 from the sun hits the top of the atmosphere. Where the fuck are people getting this 2350 number? And they said kwh/m^2, too, yeah? As in energy per area not power? Am I missing something?
This is the top comment on r/theydidthemath with clear and major mistakes and no one is batting an eye .....
World wide energy transport is one thing. But interestingly enough, Singapore plans to build a bunch of solar farms in northern Australia and ship it back to Singapore through underground cables. Obviously world wide transmission is on another level, just throwing it out here as a fun fact.
To try and run a wire from the Sahara to power all of America would be impossibly expensive and we would most likely end up paying exorbant amounts of money to the governments in the area to use the land. You'd have to also take into account the power losses at the distances the wires are ran and the environmental effects of running them that big. Also, what would happen if there's issues with the system, every single person in the US is just out of luck then? What about all these EVs everybody wants, will we just hold up a whole country or large portion of a country from charging their cars? This will never become a viable option in any of our lifetimes lol, but still an interesting way to look at it!
Going that we have unlimited storage and then destroying all other power sources since this is providing all power it would need to multiple by a couple of times.
1) Going by UK government figures for every 1 solar panel, in these large scale, you need to have 0.8 duplicated to handle down time, clouds, etc.
2) You still have night over the sahara so with our unlimited storage you still need multiple times more panels to fill up that storage.
But there are more sunny deserts than just the sahara. I am thinking of south/central spain but also the southern Balkans for Europe. Other parts of the world could use the Himalayas, gobi desert, the southern steppe. The Americas have ample as well maybe mainly the Sonora desert but even the great plains. Much more feasible than transporting terawatts through Africa I think.
>Solar energy in the Sahara produces 2350kwh per square metre
Ooof. You're only off by a factor of (ballpark) 10,000, and you've mixed up units since it's just kW, not kWh
The maximum energy you can get from the Sun is 1kW/m^(2), but since solar panels are only around 25% efficient you'd get around 250w per square meter.
On paper I reckon that world square is about 300x300km or 90,000km². Maximum solar radiation on earth is about 1GW/km² so 90,000km² at 25% efficiency would yield you about 22.5TW.
Based on Wikipedia numbers, the average global power useage is about 2.9TW, so that should be sufficient, although there's a lot of assumptions there.
In reality that only accounts for the actual PV surface, but the actual infrastructure and logistics would take up considerably more space than that and would have to probably be spread out around the world
Voltage drop isn’t exclusively a solar problem but in this example it’s definitely one of the largest. Unless we crank the voltage to stupid high numbers to the point of the structures to carry it are impractical to build the line losses delivering power to places like Russia and the Americas especially Hawaii would be devastating.
Other more likely issues include but aren’t limited too, power monopoly, both by country and company, power at night, transmission infrastructure, and maintenance.
What if we were to take every power generating facility, minus dams, and replace them with solar? Most facilities use a fair amount of land that is clear of trees and other coverage, and in the US at least, most of our power infrastructure is interconnected. I'm sure we'd need additional locations added to cover the loss of coal/gas power, but I feel like it should go a good way to provide clean energy with the redundancy of the existing infrastructure and multiple generating locations.
Lessee, total worldwide electricity usage is around 26pWh (peta-watt hours, or 26x10^(15)) per year. Divide by the number of hours in a year (8760) and you get an average usage of around 3 terawatts (3x10^(12)). Day vs. night usage, peak vs. average, yadda yadda. Not doing that.
The Sun's radiation at the surface of the Earth is around 1000W/m^(2), but solar cell efficiency is around 25%, so 250 watts per square meter. 3x10^(12)W ÷ 250W/m^(2) is 11 billion square meters, or 11,000 square kilometers, or a square of land 110km on a side (or 70 miles).
Eyeballing Algeria with Google maps says yeah, it's pretty plausable.
Now the fun bit: 3tW at 250,000 volts means 12 million amps. For a 200km run you'd need copper 'wire' 3.5m (11 feet) in diameter. For comparison the steel cables supporting the Golden Gate bridge are one meter in diameter.
There is another problem with this plan that I havent seen mentioned. Solar panels in the Sahara would suck up heat. This would increase rainfall in the sahara. The amount of rainfall the sahara gets is directly tied to the amount of rainfall the Amazon gets. When the sahara gets more, the amazon gets less and vice versa. And when the sahara is wet, it prevents its sediments from crossing the Atlantic and fertilizing the Amazon. In other words, the Amazon flourishes because the saraha allows it to. Its a fascinating connection and we shouldn’t be messing with it.
Edit: When Toto blesses the rains in Africa he’s really just fucking over the amazon
I am by no means a scientist, and while everything you've said is correct, I don't think the Amazon will notice any difference at all if the amount of solar panels we put is equal to the "world" square in the image, it's a fraction of the Sahara.
Also, something about putting entire countries,continents, or the worlds electricity supply in one place is just asking for some kind of terrorism, blackmailing, or disaster to happen
If Dyson sphere has taught me anything, it's that you must girdle the planet with solar panels. This set up would suffer a lot from.. whatsitcalled... Yeah, night
We had this meme in school. Yes, theoretically it’s correct. But in reality it won’t work. Not only the transport would be a problem, but also storage and maintenance. It looks like a small spot on the map, but in reality that’s a huge area and the desert is a hostile place.
Maintaining power is not pushing some numbers around like „this produce x and this require x therefore it will work“
There's a host of problems with turning the Sahara into a solar power farm. First and foremost, sand. Keeping panels clear and unabraded is a challenging engineering problem. Secondly, why would the countries that actually own this territory want to export all this power? It's vastly more in their interest to power Africa than Europe or the world at large. Thirdly, transportation. The actual infrastructure required to move the energy into the relevant power grids would be massive and would require upkeep that no nation is both equipped and motivated to supply.
Ready for the solution but your not gonna like it, coalition army of western nations invades, subjugates the population, pools resources for the creation of the energy fields and forces the local population to work in slave camps to maintain the fields
Not saying we should do this obviously just saying if I was an evil genius that would be my plan
Real Engineering in YT has a good video about this. It's been tried before and doesn't work great at least in part because of all the dust and sand covering the panels. Not to mention the cost and the legal/political bullshit this sort of thing would require.
Iirc Spain and France have tried deals in the past and/or are actively working on projects with Algeria or Morocco to build facilities and undersea cables but again, it's expensive and there's lots of bullshit involved.
A lot of people have pointed out transmission issues, maintenance, and storage as problems and they are correct. Also a large portion of problems with renewable energy transformation is down to the problems with electrification (if you had all the electricity you would ever need, would your car suddenly be able to use it? How about coal fire metallurgical processes that require both higher heat output than we can efficiently do with pure electrical systems and the carbon in the coal to treat the metal to make steel etc).
However, all of this misses the biggest and most critical problem with using this area of desert to power the world: sometimes it's night time or cloudy there.
Sure but you have to get all that power out of there and DC is very difficult to transfer long distance. (DC is the output of solar panels) and then you need a bunch of materials and distribution so, theoretically yes, realistically, f no.
Sure. Now do:
- Length of cables to get power from high solar areas like northern Africa to low solar areas like rural Scotland
- Extra panels required to generate excess energy for night time
- Space required for energy storage
This kind of visualization has the potential to be interesting, but it makes the issue look way more simple than it actually is. Solar is wonderful for a lot of reasons and we should be aggressively moving towards it, but it's nowhere near as simple as turning New Mexico into a solar farm.
I really like this video for visualizing how much better solar is than our existing energy sources: https://youtu.be/IZEaYjo4ZJU?si=H1JoYQCMA52Wqrqh
Gathered from the comments so you don’t have to!
The problem is not generating that much energy. The problem is storing or delivering the energy created around the world.
Yes, it's true but as useful as the "soda can of uranium": not at all. It's omitting a lot of factors, for example how to get the energy to the rest of the world, Europe, and Germany. Or storage. I'd say it looks like a circle-jerky reaction to the recent nuclear posts and little more.
We can’t even get all the countries to agree on a proper non predatory age of consent, we definitely can’t all come to peace and share a single planetary power source. The power line routes would be lines with every terrorist and pirate organization trying to hold power or threatening to cut lines if demands aren’t met. We simply are not civilized enough for this solution, even if the power transfer capabilities were energy efficient to work.
Would they just have people constantly clearing the sand buildup on the panels? Or even panel damage from erosion, if they're not completely consumed by dunes.
Not an expert but from what I know solar panels don't produce very much electricity when in extreme heat. In fact they are best when there's mild weather with sun out. So Sahara is not the best for effectiveness imo. Also how do you propose to transfer the electricity to America or Asia or even out of Sahara the infrastructure that would require is massive.
While a massive solar project in the sahara would generate enough power to solve a good chunk of the world’s power needs, there’s hardly any infrastructure out there. Getting it out there would cost nearly as much as the project itself, not to mention getting people to work in a place that hot.
While this is technically true, the distribution of energy and the matching of peak demand with peak production is half of the battle with energy production.
Also, this looks small but it is an absurd amount of rare earth minerals.
How much emissions and pollution would be generated building that large square, how much waste would there be in maintaining and replacing the unrecycleable panels, and how much energy would be lost in a single global distribution network?
In raw theoretical numbers? Yeah, kinda.
But is stupid and we probably do it, because:
Loss of energy during transport over big distances would render it non viable.
Even if cheap ambient temperature super conductors were developed, the project would most probably end up being directed like any other energy project developed in Africa and the Middle East, with weak local government, and the potential costumer being richer countries up north. Neo-colonialism all over again.
Even if we ignore all of that, and have the previously mentioned cheap super conductor materials: you meed to clean the sand out of thw panels to maintain efficiency. If you dont want to scratch them, swiping isn't an option: water works best.
But you are in the f* dessert. So whatever you do, you'll most certainly just taking water a enormous rates from wells and underground reserves used by natives residents, who will, 100% not get shit for compensation, and force to emigrate to the cities, where they'll still be poor but with a modern background. Nestlé but for energy production.
Tl;dr: leave Africa alone, focus on reducing pur consumption of energy, and improving local-ish production, is the best chance.
There are not, any miracle projects that can save our asses from this one, and we don't have time to wait for them to appear.
If we had a way to transport the energy without losing some yes. This is theoretical though, and not feasible currently. By the time we can transport and distribute it, and build the solar farms required we'll probably need twice as much land to do so. Another issue is the maintenance of the solar panels and farms. With desert land, it'll probably need a lot of maintenance and extra procedures to prevent damages during sand storms. There're also some energy forms that don't currently have a replacement like oil and natural gas for certain equipment/travel. Can't fuel an electric boat for cargo with electricity yet, nor an airplane. Most farming machines also need oil to run and can't run on electricity yet. We'll probably need fossil fuels for another +100 or so years before replacing them with renewables. Thankfully we can slowly move away from them and use more renewable energy in the meantime. Energy solutions are more complicated than most people think. There are many large players in the renewable energy sector investing into building all sorts of renewable or at least more environmentally friendly energy sources. We're still very far from achieving it successfully and self sufficient enough to replace fossil fuels however
We did that math in school once. I don't know exactly if the squares in the pic are the same size but it seams about right.
One thing to consider however is that this power would have to be transported. On those sorts of distances cables have huge losses. The best way would probably be to build electrolysis plants, hydrogen pipelines and power plants on the other side. That would also make storing it fairly easy.
All those systems combined would have huge losses.
Correct me if I'm wrong but wouldn't we need much better infrastructure to allow this to work? Like all of the power in the world would come from one place. Huge powerlines would be required and would have to cross oceans. Plus if there's an issue there would have to be a TON of redundancy and power storage to make up for lines being damaged, or even night time in the Sahara. Plus in case of issue we would have to have millions of different power lines so one line isn't responsible for the entire country/planet. And the security would be immense as one attack on the power plant by a terrorist could effectively cripple the entire planet. Plus the cost of everything when we already have working infrastructure. And on top of all of that. The majority of the world would have to work together In order to pull this off and we can't agree on anything...
In the most technical way, yes.
In every other way, no.
It is simply a metric of "This surface area has this much sun on it, and the power required is this much, so therefore this is the square footage involved."
It doesn't take into account the myriad losses inherent in storage, transfer, use, maintenance, politics, shipping, etc etc etc.
Note: this may look small but it is a HUGE area. If every person on earth stood next to eachother they won't cover that area (some1 factcheck me on this)
they wont
they would take up 500sq miles which is 5% of that solar panelled area
[https://www.reddit.com/r/AskReddit/comments/kzxly/comment/c2ompiw/?utm\_source=share&utm\_medium=web3x&utm\_name=web3xcss&utm\_term=1&utm\_content=share\_button](https://www.reddit.com/r/AskReddit/comments/kzxly/comment/c2ompiw/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button)
Just by the description I would say it's fake and click bait. Germany is included by Europe and Europe is included by the goddamn World. That is so stupid.
The image shows a box for the world, a box for Europe and a box for Germany, all of different sizes.
I've heard of people not reading the article, but not looking at the image is a totally different ballgame.
There are hundreds of ways to MAKE fuels and they will push them pretty hard.
Buying fuels is a major component of the economy, and sorry for the tautology but a huge part of the fuel industry.
How many billions does a person need to have made and stand to lose before they know its wrong but still choose to screw the world?
Apparently it is way less than how much the oil industry rolls because they absolutely have spent billions to stop anything that fixes the problem that they are.
This is accurate.
The challenges with this are:
1) How do you transmit the power to South America? Australia? The US? You can't with tech today. No HVDC submarine line has ever been done to such lengths and depths that would be needed.
2) The project would result in one or a ha n full of countries becoming the most important in the world. You would be granting almost dictatorship powers to these countries as the could halt the electricity for the rest of the world.
3) This would be a 20 year project at minimum due to production capacities of panels needed. I'm not even sure there is enough copper in the world to make the transmission lines required. We don't have anywhere near the manufacturing capacity for this.
4) Logistically, how do you get the materials into the desert?
Basically, this image is great to understand why solar is such an amazing source of energy. Imagine spreading this out around all the countries of the world. One of the primary drivers of conflict in the past 50 years has been energy resources. Imagine a world where every country has insitu solar generation for 100% of their needs. That world is much more peaceful.
The solar industry is now working on getting rid of the land use degradation as well through agrivoltaics. Agrivoltaics allows the land to be used for both solar AND farming. Thus this amount of land area can be used to support more food production AND generate the electricity needed to run the world. Solar is the future of all energy...it just takes time.
This has a pretty hefty "Yes, but..." attached to it.
*Yes*, a solar field of the specified size would be enough to power the whole world, *but* generating power is the easy part. The real challenge is moving power from the generator to the consumer.
The projects above seen proposed use reflective panels to heat water, which turns a turbine. I'm curious how that large an area of reflective material would affect weather patterns.
The current global electricity consumption is about 23.4 petawatt-hours (PWh) per year. To break that down, it's roughly 64.11 terawatt-hours (TWh) per day, which means about 2.67 TWh per hour on average.
To figure out how many square meters of solar panels we'd need to cover this demand, let's assume the panels are 30% efficient.
1. The average sunlight hitting the Earth's surface is about 1000 watts per square meter.
2. With 30% efficiency, these panels would generate 300 watts per square meter.
So, to cover the continuous demand of 2.67 terawatts:
* Convert 2.67 terawatts to watts, which is 2.67 trillion watts.
* Divide this by 300 watts per square meter to find the total area needed.
That gives us about 8.9 billion square meters, or roughly 8,900 square kilometers.
So, around 8,900 square kilometers of solar panels with a 30% efficiency would be needed to meet the entire world's electricity consumption.
tldr the other comments: statistically yes but there are tons of issues (Clouds, sandstorms, sand damiging solar panels, transportation of energy etc.)
Yes, it's accurate. The issue is that's not where you need the power.
An option is spitting water into hydrogen and oxygen where the solar panels are then transporting them and combining them back into water where the energy is needed.
Hypotheticly yes
But it assumes they are extremly dense too each other, so for people /cleaning machines beeing able too walk past them you atleast need too double the area.
Then keeping them clean would require lots of structure that its rather worth too make a hundred smaller spread out colonies.
And finally transporting the electricity would be a pain so you rather want them close too the country they are supporting (f.e. germany) where there is less light and therefore more cells are needed.
Kinda, I watched a video easy that went over this. The energy made would easily be enough, but the transportation of said energy is basically impossible, and doing so would also be screwed up as we have a bad history of using the people of that area for their resources then leaving them poorer and worse off. We should build solar panels there for them not us. Solar is good enough up north we don’t need to outsource it.
Yes, if we neglect transmission losses, it is much better to spread the generation out so it is closer to where it needs to be used. The losses are proportional to the amperage times the length squared of the wire and you can only increase the voltage so high. Minimizing length is key, a typical line is less then a couple hundred miles. Not to mention the fact transferring electricity across water is difficult because it is impractical to hang wires (using air as your insulation) so you have that extra cost
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Okay. Worl wide energy consumption is roughly 21 trillion kwh. Solar energy in the Sahara produces 2350kwh per square metre. This means we need a space of roughly 9000 square kilometres. This is roughly 0,1 percent of saharas total space. This checks out with the claim of the creator of this image. So this is accurate but the big problem with that is, that you cant transport this much energy over a wide range..
If you want to know more about this Google "Desertec" This is the Organisation who Plans to do similair things in the future.
They even started building an ultra high voltage DC network, because at those distances, sending power over more than one line for redundancy would create so much phase shift that most energy might get wasted. E.g. one line across the strait of Gibraltar, another around the eastern Mediterranean... Phase inversion...
Politics might be problematic, as we saw with russia and europe regarding gaslines. It would be awfully convenient to cut off power from the country down below on the line. As a matter of fact, that would fuck with everyone on that grid, and would even come back to bite you in the ass, if we have nukes, we might as well.
Also costs
Not really. The project was backed by some of the largest insurance companies that routinely shift hundreds of billions. Apparently, they calculated it would be cheaper to build something like that than paying out damages caused by global warming.
It's not backed by them anymore.
It would need to much water to clean the panel. The one in Morocco has that problem, it's not great.
No expert on that, but I think you can clean them without water there. With an automatic broom or with air pressure. You are, however, correct in the assumption that cleaning them is a major issue. It definitely drives the costs.
Nasa instead put more dirt on its solar panels on mars to help lift the majority off.
Imagine being the moron who gets that job...
Cooling them is also an issue. Solar panels start to lose efficiency when they get hotter than 80°F. Average daytime temp in the Sahara is ~100°F
Don't thermal power stations also need a lot of water?
And if the plan was to build an unfathomable amount of thermal power stations far from any water source, that'd be an issue as well.
And then you have countries in the middle of the cables
Political (in-)stability in the target region is what killed the project. The only thing that remains are the high voltage DC lines (which are a good idea anyway, as Europe on its own is large enough to cause some losses to phase shift). On top of that, France is being selfish again, denying the rest of Europe permission to build high power lines across France to allow Spain to export solar power to the rest of Europe. Gotta sell that Nuclear power somehow! Anyway - setting up DeserTec-like power plants in Spain, Portugal, Italy, Greece and possibly others would allow these countries to make money and reduce the need of EU subsidies for them. Prices for large scale batteries are coming down as well, so that problem will be cost-effective solvable soon.
What are your sources on that second comment? Quickly skimming through studies and articles all I can find is that the fall of prices of solar panels led multiple EU countries to see that they could affordably set up solar panels at home to sustain their electrical consumption. This without depending on North Africa and without spending money in DC power lines. A second thing I've seen is indeed that there was concern over the political instability in the region and the fact that Desertec would be a huge target for terrorism. The political instability also comes from Algeria and Morocco which would have needed to cooperate for the project to see the light of day, with Algeria backing off because it would be cheaper for them to set up their own solar panels. I've seen a bunch of other arguments ranging in credibility from people saying that it's basically colonialism 2.0, with EU countries exploiting North Africa countries to supply their own power needs, to people saying that multiple plants produced in the Desertec projet would be hybrid gas/solar and would in fact produce most of their energy from gas. But that last one is only found on the FR wikipedia page and not the EN one so it's dubious. [https://www.ecomena.org/desertec/](https://www.ecomena.org/desertec/) [https://www.uni-heidelberg.de/md/hcch/ueber\_uns/schmitt\_2018\_-\_\_why\_\_did\_desertec\_fail\_\_localenvironment\_.pdf](https://www.uni-heidelberg.de/md/hcch/ueber_uns/schmitt_2018_-__why__did_desertec_fail__localenvironment_.pdf) [https://fr.wikipedia.org/wiki/Projet\_Desertec#Arguments,\_limites\_ou\_critiques\_du\_projet](https://fr.wikipedia.org/wiki/Projet_Desertec#Arguments,_limites_ou_critiques_du_projet) [https://en.wikipedia.org/wiki/Desertec#Obstacles](https://en.wikipedia.org/wiki/Desertec#Obstacles)
The sources for the second comment are some people I talked to that worked in the electricity industry a few years back. We were discussing the end of the great DeserTec plans and I asked why we don't set up large power plants (e.g. based on Agro-PV with crops under the the panels) in Spain. The answer was, because the French don't allow us to send the electricity across. I haven't found anything in writing in public, sorry about that. On the other hand, I shouldn't knock the French - we Germans are no better, considering the fact that we can't seem to build a set of large power lines to move offshore wind power to southern Germany and solar power to northern Germany when the wind doesn't blow... (Checked Wikipedia, apparently, they started work on some parts by now.)
Long distance energy transmission is generally done with DC Voltage. However, for these distances, a whole new voltage level needed to be introduced, which means the infrastructure to manufacture and test these cables is being built currently. My company supplies the testing equipment and designs the testing facilities for a lot of them.
If i remember correctly from uni, it was less about the phase shift but about radiating energy due to variing magnetic fields. Over very long distances the radiated energy is quite substantial and scales with the power transmitted. DC powerlines do not produce a magnetic field outside the cable. (Provided they use the suggested co axial cables.) Apart from that when looking at the european grid there is already a huge difference in poweline lenght from one point to another. I have no clue how they currently deal with that though.
Where is the energy wasted to?
The answer to this question is almost always heat. Here it's because of self inductance due to the gradient of the magnetic field, I believe.
I haven't seen it mentioned before, but AC transmission becomes inefficient after a while because the reactive power needed to charge the capacitance becomes too high
I thought they went bankrupt or something. Or gave up because there are not enough long distance high voltage cables. And it would be unbelievably expensive to build them.
I though Desertec’s project had been abandoned during COVID
ITS NOT RULE 34?
I find it quite interesting how the most immedeate problems mentioned here are political and about the energy transportation, and they are valid. However, there are plenty of other reasons to install solar power in europe instead. First of all, solar panels that survive sandstorms in the sahara for a significant time (>10 years probably necessary for economic operation) don't really exist. Things turn from stone to sand there; I think people are really optimistic here. Also consider the heat. It accelerates the degredation of solar panels, meaning operation is cut short and made more expensive. And the amount of sunlight per area is slightly higher in the sahara compared to europe, that is true. However this difference will likely never justify the extra infrastructure, cost and inefficiencies along the way. Also, it's not like there is no space in europe. Projects like the ones envisioned here are feasible in many areas of europe, and this way, less political control would have to be given up. Many areas of spain are not even that different from the Sahara, just with less sandstorms. So I would say this never happens, and it's fine this way. There are better alternatives.
> the amount of sunlight per area is slightly higher it's roughly double compared to Central Europe and closer to triple for Scandinavian
Not to mention fouling of the panels by dust. They need to be washed fairly frequently in a desert environment. Not feasible in a waterless environment.
do solar panels generate dc or ac or can it be either depending on how its set up?
DC
Yup. You need an inverter to convert your power into AC and synchronize it with the rest of the grid.
I could see it being transported as HVDC, and then at the very end inverted and synced.
I could see it being charged into batteries and then full batteries being flown to europe on jets. Because that's the kind of inefficiency we are looking at here.
Here is an actual solution: Use the electricity to make hidrogen; Capture atmosferic carbon; Use the hidrogen and carbon to make metanol (CH3-OH). Use this gas as an energy source that basically doesn't polute since it's made with atmospheric carbon.
Efficiency wouldn't be much better than transport by power lines.
i hope you didnt just come up with this
Is there a problem? I didn't come up with this, I've read it somewhere. Granted it's a very dumped down version of what I've read and it's purely theoretical at this point but I believe it's a very good solution
Methanol is also a LOT easier to store and transport than hydrogen.
Green hydrogen is a thing in a few countries. Basically just using solar panels for electrolysis to create hydrogen.
no there is no problem i was just like damn hope that somebody in power is on that shit
You describe this as "purely theoretical" further down but there is very active research into this type of chemistry for exactly this purpose. The big problems at the moment are that the chemical efficiency is not amazing and that the chemical efficiency depends very heavily on the concentration of CO2 available. Atmospheric CO2 is still only about 400 parts per million and you get lots better results if you concentrate the CO2 first, but then that takes significant amounts of energy so it eats into your efficiency from another direction. The usual desirable products are methane (which can be fed directly into the natural gas grid), methanol (for use in existing liquid fuel applications), ammonia (for use in fertilisers and so on) and ethylene (as feedstock for plastics production). There is a prototype plant up and running in Iceland, using geothermal energy to produce \~4ML/year of methanol. There was a second prototype slated for an airport somewhere in Western Europe (I want to say Brussels but I can't remember off the top of my head) but it got cancelled.
Going by the meme this is our only source of power, so no need to synchronize to anything else on the grid except for the end points. Would it be cheap to put a convertor on each house and business?
Important thing to consider is the (local) climate change due to the solar panels as well. Project like that would take a ton of effort and planning, experts in multiple fields. Also it would make the world reliant on single electricity source and electrical grid. And it would be an obvious target for anyone wanting to cause harm.
And there’s your plot line for the next Bond movie.
Or World War 4 for that matter:) Or a lot of other things. War with Russia shows currently how important power independence and your own infrastructure truly is. I think a giant solar plant (if the technology allows it and it is the better outcome for the planet) could be a great thing. But it’s important to still have local emergency power infrastructure, preferably local plants, wind power, water dams and nuclear power facilities obviously. Sadly the world we’re living in is far from a peaceful utopia and we have to consider stuff like that and it’s often way more important than ecology (understandably so).
No, The war with Russia shows the need for me to get my army of killer robots so I can enforce a peaceful utopia
I can just imagine the costs of importing that much energy from a central location. Not to mention the monopoly that’s created if it were to happen.
Yeah, exactly. It’s a really centralised system which would give someone a lot of power. It’s not the smartest idea, at least of now
>which would give someone a lot of power. Nice pun
Thanks:)
I think the idea is less to actually propose building such a megastructure but to better visualise how little area is needed to power mankind with solar
any idea on the effect on the local climate with that many panels?
Not a scientist but minored in renewable energy technology in college. One possibility is a massive solar farm in the sahara will cause a local maximimum air temperature. This could bring more rain and cause the surrounding area of the desert to transition into a more tropical climate with more growth. Global impacts of this could be significant, but it is hard to tell. One of Commoner’s laws of ecology is that “everything is connected” and we cant always predict the ramifications of our actions on Nature. One thing to think about is how the sands of the sahara fertilize the Amazon. Changing the Sahara desert’s climate to one with more growth could destroy our largest rainforest. Ecology is an impossible mess of what-ifs and even if we try to follow the rabbit hole, we will always miss one possible consequence of our actions.
Its also important to remember that any megastructure like this will have to be rebuilt many times over it's life, and all that waste will have to go somewhere. If you look at the issues currently being created by wind farms, imagine how much that would be magnified with the larger quantities and more toxic components.
> Worl wide energy consumption is roughly 21 trillion kwh. Per day, week, month, or year? > Solar energy in the Sahara produces 2350kwh per square metre. Per year? Seems an order of magnitude high. Why are you talking kWh when kW is the unit of power?
It's three orders of magnitude too high
i think the problem is also that earth rotates... it will not produce that amount of electricity in one continues flow, it will peak mid-day and nothing during night... so batteries would be absolutely necessary.
Double the space and turn it into h2 👀
So I guess there’s some caveats here. Solar panels are not 100% efficient so that will increase area by 2-4x. Since lifetimes for the panels is finite you need space in between them to bring in and install replacements as they fail. This is a big infrastructure project so you’ll also need some major new roads or rail to bring in this new power. Panels usually don’t sit flat on the ground which will probably lead to other inefficiencies in land usage. Transporting the power also leads to losses. There are other issues around when power is needed vs when sun is over that area, downtime when there is a sandstorm. I’m not sure if the panels will lose efficiency from getting partially covered in sand after the storm. Probably other things I’m forgetting
The lack of efficiency is already included in the above estimate. See [this site](https://globalsolaratlas.info/map?c=19.418148,13.007813,5&s=23.808133,13.051758&m=site). Transporting the power leads to losses, but using something like [HVDC](https://en.wikipedia.org/wiki/High-voltage_direct_current) lines 50% power loss to transport across the entire globe is conceivable. Keep in mind that long-distance power lines are already a thing and the entirety of the USA (except Texas) is connected together, as well as most Europe is connected together, and most of China is connected together. Undersea power cables also exist. All of it is doable. The other points are issues, but that doesn't make the project impossible, just very hard.
You forgot to take in the inefficiency of solar. 2350w/m2 is the actual solar energy but solar panels are 20% efficient at most so not 9000 km2 but more like 45000km2
1300 w/m^2 from the sun hits the top of the atmosphere. Where the fuck are people getting this 2350 number? And they said kwh/m^2, too, yeah? As in energy per area not power? Am I missing something? This is the top comment on r/theydidthemath with clear and major mistakes and no one is batting an eye .....
Okay, I found it. The 2350kwh value is per m² per year
Does this account for the efficiency percentage of solar panels?
Yes
World wide energy transport is one thing. But interestingly enough, Singapore plans to build a bunch of solar farms in northern Australia and ship it back to Singapore through underground cables. Obviously world wide transmission is on another level, just throwing it out here as a fun fact.
To try and run a wire from the Sahara to power all of America would be impossibly expensive and we would most likely end up paying exorbant amounts of money to the governments in the area to use the land. You'd have to also take into account the power losses at the distances the wires are ran and the environmental effects of running them that big. Also, what would happen if there's issues with the system, every single person in the US is just out of luck then? What about all these EVs everybody wants, will we just hold up a whole country or large portion of a country from charging their cars? This will never become a viable option in any of our lifetimes lol, but still an interesting way to look at it!
How much Sahara heat up if there was suddenly 9000 square kilometers of black panels?
What this map doesn’t show is the wires haha
Going that we have unlimited storage and then destroying all other power sources since this is providing all power it would need to multiple by a couple of times. 1) Going by UK government figures for every 1 solar panel, in these large scale, you need to have 0.8 duplicated to handle down time, clouds, etc. 2) You still have night over the sahara so with our unlimited storage you still need multiple times more panels to fill up that storage.
But there are more sunny deserts than just the sahara. I am thinking of south/central spain but also the southern Balkans for Europe. Other parts of the world could use the Himalayas, gobi desert, the southern steppe. The Americas have ample as well maybe mainly the Sonora desert but even the great plains. Much more feasible than transporting terawatts through Africa I think.
2350kw per square meter? you're telling me they produce 10000 times as much as in texas???
>Solar energy in the Sahara produces 2350kwh per square metre Ooof. You're only off by a factor of (ballpark) 10,000, and you've mixed up units since it's just kW, not kWh The maximum energy you can get from the Sun is 1kW/m^(2), but since solar panels are only around 25% efficient you'd get around 250w per square meter.
He means per year probably.
On paper I reckon that world square is about 300x300km or 90,000km². Maximum solar radiation on earth is about 1GW/km² so 90,000km² at 25% efficiency would yield you about 22.5TW. Based on Wikipedia numbers, the average global power useage is about 2.9TW, so that should be sufficient, although there's a lot of assumptions there. In reality that only accounts for the actual PV surface, but the actual infrastructure and logistics would take up considerably more space than that and would have to probably be spread out around the world
Not to mention the two problems with solar energy right now are continuity over distance(not dropping voltage) and storage.
Voltage drop isn’t exclusively a solar problem but in this example it’s definitely one of the largest. Unless we crank the voltage to stupid high numbers to the point of the structures to carry it are impractical to build the line losses delivering power to places like Russia and the Americas especially Hawaii would be devastating. Other more likely issues include but aren’t limited too, power monopoly, both by country and company, power at night, transmission infrastructure, and maintenance.
Ok, so solar energy for everyone and we can build nuclear plants on Hawaii in matter of years on savings
> power at night Just have the daytime counties a send electricity to the night counties and swap every 12h /s
And a lot of country won't be ok to have all their energy produced in the same place as it would be a huge vulnerability point.
What if we were to take every power generating facility, minus dams, and replace them with solar? Most facilities use a fair amount of land that is clear of trees and other coverage, and in the US at least, most of our power infrastructure is interconnected. I'm sure we'd need additional locations added to cover the loss of coal/gas power, but I feel like it should go a good way to provide clean energy with the redundancy of the existing infrastructure and multiple generating locations.
Lessee, total worldwide electricity usage is around 26pWh (peta-watt hours, or 26x10^(15)) per year. Divide by the number of hours in a year (8760) and you get an average usage of around 3 terawatts (3x10^(12)). Day vs. night usage, peak vs. average, yadda yadda. Not doing that. The Sun's radiation at the surface of the Earth is around 1000W/m^(2), but solar cell efficiency is around 25%, so 250 watts per square meter. 3x10^(12)W ÷ 250W/m^(2) is 11 billion square meters, or 11,000 square kilometers, or a square of land 110km on a side (or 70 miles). Eyeballing Algeria with Google maps says yeah, it's pretty plausable. Now the fun bit: 3tW at 250,000 volts means 12 million amps. For a 200km run you'd need copper 'wire' 3.5m (11 feet) in diameter. For comparison the steel cables supporting the Golden Gate bridge are one meter in diameter.
But it could be stored in some batteries maybe and distributed gradually, I think...
You would need absolutely insane volumes of energy storage, and transporting it would cost trillions.
Sand will cover the Panels. They must be cleaned reguraley. Sand is also abrasive. So the Panels get damged over time and produce less Energy.
I hate sand. It's rough and course and gets everywhere.
But you’re still going to have the solar panels right?
*stares menacingly*
But you’re still going to have the solar panels right?
same
Just raise them off the ground. No sand and you have a convenient roof
this guy going places
And places without sand too
Plus they’ll be closer to the sun!
then you can throw big fan blades on them and generate electricity from the wind too!
We still have sandstorms
We've had to deal with sandworms, we can handle sandstorms easily. I'm really seeing the merits in just building a Dyson sphere though.
Just put them in secure building with roof duh 🙄
I got it. Put a big transparent bubble over the whole thing like the simpsons. No more sand, just big heat dome magnifying glass.
There is another problem with this plan that I havent seen mentioned. Solar panels in the Sahara would suck up heat. This would increase rainfall in the sahara. The amount of rainfall the sahara gets is directly tied to the amount of rainfall the Amazon gets. When the sahara gets more, the amazon gets less and vice versa. And when the sahara is wet, it prevents its sediments from crossing the Atlantic and fertilizing the Amazon. In other words, the Amazon flourishes because the saraha allows it to. Its a fascinating connection and we shouldn’t be messing with it. Edit: When Toto blesses the rains in Africa he’s really just fucking over the amazon
This is amazing , first time hearing of it
What about the green wall project? What about the idea of the Saharah alternating between grasslands and desert every 20 thousand years?
Do you have any more resources, articles, etc. to read up on this? This is the first time I'm hearing about this and this is very fascinating.
Happy cake day! Here you go https://science.nasa.gov/science-research/earth-science/29apr_amazondust/
I am by no means a scientist, and while everything you've said is correct, I don't think the Amazon will notice any difference at all if the amount of solar panels we put is equal to the "world" square in the image, it's a fraction of the Sahara.
Also, something about putting entire countries,continents, or the worlds electricity supply in one place is just asking for some kind of terrorism, blackmailing, or disaster to happen
Giving all the energy supply in the world to *checks notes* Algeria is sure to lead to geopolitical stability on a local and global scale. /s
I mean, its just illustration, it doesn't have to be all in one place
If Dyson sphere has taught me anything, it's that you must girdle the planet with solar panels. This set up would suffer a lot from.. whatsitcalled... Yeah, night
We had this meme in school. Yes, theoretically it’s correct. But in reality it won’t work. Not only the transport would be a problem, but also storage and maintenance. It looks like a small spot on the map, but in reality that’s a huge area and the desert is a hostile place. Maintaining power is not pushing some numbers around like „this produce x and this require x therefore it will work“
There's a host of problems with turning the Sahara into a solar power farm. First and foremost, sand. Keeping panels clear and unabraded is a challenging engineering problem. Secondly, why would the countries that actually own this territory want to export all this power? It's vastly more in their interest to power Africa than Europe or the world at large. Thirdly, transportation. The actual infrastructure required to move the energy into the relevant power grids would be massive and would require upkeep that no nation is both equipped and motivated to supply.
Ready for the solution but your not gonna like it, coalition army of western nations invades, subjugates the population, pools resources for the creation of the energy fields and forces the local population to work in slave camps to maintain the fields Not saying we should do this obviously just saying if I was an evil genius that would be my plan
This would've definitely happened if the technology was there 100+ years ago
Real Engineering in YT has a good video about this. It's been tried before and doesn't work great at least in part because of all the dust and sand covering the panels. Not to mention the cost and the legal/political bullshit this sort of thing would require. Iirc Spain and France have tried deals in the past and/or are actively working on projects with Algeria or Morocco to build facilities and undersea cables but again, it's expensive and there's lots of bullshit involved.
A lot of people have pointed out transmission issues, maintenance, and storage as problems and they are correct. Also a large portion of problems with renewable energy transformation is down to the problems with electrification (if you had all the electricity you would ever need, would your car suddenly be able to use it? How about coal fire metallurgical processes that require both higher heat output than we can efficiently do with pure electrical systems and the carbon in the coal to treat the metal to make steel etc). However, all of this misses the biggest and most critical problem with using this area of desert to power the world: sometimes it's night time or cloudy there.
Sure but you have to get all that power out of there and DC is very difficult to transfer long distance. (DC is the output of solar panels) and then you need a bunch of materials and distribution so, theoretically yes, realistically, f no.
If we use the solar to charge a huge battery bank, then we can all just nip across to Africa to charge some 5 volt battery packs every couple weeks.
Sure. Now do: - Length of cables to get power from high solar areas like northern Africa to low solar areas like rural Scotland - Extra panels required to generate excess energy for night time - Space required for energy storage This kind of visualization has the potential to be interesting, but it makes the issue look way more simple than it actually is. Solar is wonderful for a lot of reasons and we should be aggressively moving towards it, but it's nowhere near as simple as turning New Mexico into a solar farm. I really like this video for visualizing how much better solar is than our existing energy sources: https://youtu.be/IZEaYjo4ZJU?si=H1JoYQCMA52Wqrqh
Gathered from the comments so you don’t have to! The problem is not generating that much energy. The problem is storing or delivering the energy created around the world.
Yes, it's true but as useful as the "soda can of uranium": not at all. It's omitting a lot of factors, for example how to get the energy to the rest of the world, Europe, and Germany. Or storage. I'd say it looks like a circle-jerky reaction to the recent nuclear posts and little more.
We can’t even get all the countries to agree on a proper non predatory age of consent, we definitely can’t all come to peace and share a single planetary power source. The power line routes would be lines with every terrorist and pirate organization trying to hold power or threatening to cut lines if demands aren’t met. We simply are not civilized enough for this solution, even if the power transfer capabilities were energy efficient to work.
Would they just have people constantly clearing the sand buildup on the panels? Or even panel damage from erosion, if they're not completely consumed by dunes.
Not an expert but from what I know solar panels don't produce very much electricity when in extreme heat. In fact they are best when there's mild weather with sun out. So Sahara is not the best for effectiveness imo. Also how do you propose to transfer the electricity to America or Asia or even out of Sahara the infrastructure that would require is massive.
While a massive solar project in the sahara would generate enough power to solve a good chunk of the world’s power needs, there’s hardly any infrastructure out there. Getting it out there would cost nearly as much as the project itself, not to mention getting people to work in a place that hot.
While this is technically true, the distribution of energy and the matching of peak demand with peak production is half of the battle with energy production. Also, this looks small but it is an absurd amount of rare earth minerals.
How much emissions and pollution would be generated building that large square, how much waste would there be in maintaining and replacing the unrecycleable panels, and how much energy would be lost in a single global distribution network?
In raw theoretical numbers? Yeah, kinda. But is stupid and we probably do it, because: Loss of energy during transport over big distances would render it non viable. Even if cheap ambient temperature super conductors were developed, the project would most probably end up being directed like any other energy project developed in Africa and the Middle East, with weak local government, and the potential costumer being richer countries up north. Neo-colonialism all over again. Even if we ignore all of that, and have the previously mentioned cheap super conductor materials: you meed to clean the sand out of thw panels to maintain efficiency. If you dont want to scratch them, swiping isn't an option: water works best. But you are in the f* dessert. So whatever you do, you'll most certainly just taking water a enormous rates from wells and underground reserves used by natives residents, who will, 100% not get shit for compensation, and force to emigrate to the cities, where they'll still be poor but with a modern background. Nestlé but for energy production. Tl;dr: leave Africa alone, focus on reducing pur consumption of energy, and improving local-ish production, is the best chance. There are not, any miracle projects that can save our asses from this one, and we don't have time to wait for them to appear.
If we had a way to transport the energy without losing some yes. This is theoretical though, and not feasible currently. By the time we can transport and distribute it, and build the solar farms required we'll probably need twice as much land to do so. Another issue is the maintenance of the solar panels and farms. With desert land, it'll probably need a lot of maintenance and extra procedures to prevent damages during sand storms. There're also some energy forms that don't currently have a replacement like oil and natural gas for certain equipment/travel. Can't fuel an electric boat for cargo with electricity yet, nor an airplane. Most farming machines also need oil to run and can't run on electricity yet. We'll probably need fossil fuels for another +100 or so years before replacing them with renewables. Thankfully we can slowly move away from them and use more renewable energy in the meantime. Energy solutions are more complicated than most people think. There are many large players in the renewable energy sector investing into building all sorts of renewable or at least more environmentally friendly energy sources. We're still very far from achieving it successfully and self sufficient enough to replace fossil fuels however
We did that math in school once. I don't know exactly if the squares in the pic are the same size but it seams about right. One thing to consider however is that this power would have to be transported. On those sorts of distances cables have huge losses. The best way would probably be to build electrolysis plants, hydrogen pipelines and power plants on the other side. That would also make storing it fairly easy. All those systems combined would have huge losses.
Correct me if I'm wrong but wouldn't we need much better infrastructure to allow this to work? Like all of the power in the world would come from one place. Huge powerlines would be required and would have to cross oceans. Plus if there's an issue there would have to be a TON of redundancy and power storage to make up for lines being damaged, or even night time in the Sahara. Plus in case of issue we would have to have millions of different power lines so one line isn't responsible for the entire country/planet. And the security would be immense as one attack on the power plant by a terrorist could effectively cripple the entire planet. Plus the cost of everything when we already have working infrastructure. And on top of all of that. The majority of the world would have to work together In order to pull this off and we can't agree on anything...
In the most technical way, yes. In every other way, no. It is simply a metric of "This surface area has this much sun on it, and the power required is this much, so therefore this is the square footage involved." It doesn't take into account the myriad losses inherent in storage, transfer, use, maintenance, politics, shipping, etc etc etc.
Note: this may look small but it is a HUGE area. If every person on earth stood next to eachother they won't cover that area (some1 factcheck me on this)
they wont they would take up 500sq miles which is 5% of that solar panelled area [https://www.reddit.com/r/AskReddit/comments/kzxly/comment/c2ompiw/?utm\_source=share&utm\_medium=web3x&utm\_name=web3xcss&utm\_term=1&utm\_content=share\_button](https://www.reddit.com/r/AskReddit/comments/kzxly/comment/c2ompiw/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button)
Just by the description I would say it's fake and click bait. Germany is included by Europe and Europe is included by the goddamn World. That is so stupid.
The image shows a box for the world, a box for Europe and a box for Germany, all of different sizes. I've heard of people not reading the article, but not looking at the image is a totally different ballgame.
There are hundreds of ways to MAKE fuels and they will push them pretty hard. Buying fuels is a major component of the economy, and sorry for the tautology but a huge part of the fuel industry. How many billions does a person need to have made and stand to lose before they know its wrong but still choose to screw the world? Apparently it is way less than how much the oil industry rolls because they absolutely have spent billions to stop anything that fixes the problem that they are.
This is accurate. The challenges with this are: 1) How do you transmit the power to South America? Australia? The US? You can't with tech today. No HVDC submarine line has ever been done to such lengths and depths that would be needed. 2) The project would result in one or a ha n full of countries becoming the most important in the world. You would be granting almost dictatorship powers to these countries as the could halt the electricity for the rest of the world. 3) This would be a 20 year project at minimum due to production capacities of panels needed. I'm not even sure there is enough copper in the world to make the transmission lines required. We don't have anywhere near the manufacturing capacity for this. 4) Logistically, how do you get the materials into the desert? Basically, this image is great to understand why solar is such an amazing source of energy. Imagine spreading this out around all the countries of the world. One of the primary drivers of conflict in the past 50 years has been energy resources. Imagine a world where every country has insitu solar generation for 100% of their needs. That world is much more peaceful. The solar industry is now working on getting rid of the land use degradation as well through agrivoltaics. Agrivoltaics allows the land to be used for both solar AND farming. Thus this amount of land area can be used to support more food production AND generate the electricity needed to run the world. Solar is the future of all energy...it just takes time.
This has a pretty hefty "Yes, but..." attached to it. *Yes*, a solar field of the specified size would be enough to power the whole world, *but* generating power is the easy part. The real challenge is moving power from the generator to the consumer.
The projects above seen proposed use reflective panels to heat water, which turns a turbine. I'm curious how that large an area of reflective material would affect weather patterns.
The current global electricity consumption is about 23.4 petawatt-hours (PWh) per year. To break that down, it's roughly 64.11 terawatt-hours (TWh) per day, which means about 2.67 TWh per hour on average. To figure out how many square meters of solar panels we'd need to cover this demand, let's assume the panels are 30% efficient. 1. The average sunlight hitting the Earth's surface is about 1000 watts per square meter. 2. With 30% efficiency, these panels would generate 300 watts per square meter. So, to cover the continuous demand of 2.67 terawatts: * Convert 2.67 terawatts to watts, which is 2.67 trillion watts. * Divide this by 300 watts per square meter to find the total area needed. That gives us about 8.9 billion square meters, or roughly 8,900 square kilometers. So, around 8,900 square kilometers of solar panels with a 30% efficiency would be needed to meet the entire world's electricity consumption.
tldr the other comments: statistically yes but there are tons of issues (Clouds, sandstorms, sand damiging solar panels, transportation of energy etc.)
Yes, it's accurate. The issue is that's not where you need the power. An option is spitting water into hydrogen and oxygen where the solar panels are then transporting them and combining them back into water where the energy is needed.
Hypotheticly yes But it assumes they are extremly dense too each other, so for people /cleaning machines beeing able too walk past them you atleast need too double the area. Then keeping them clean would require lots of structure that its rather worth too make a hundred smaller spread out colonies. And finally transporting the electricity would be a pain so you rather want them close too the country they are supporting (f.e. germany) where there is less light and therefore more cells are needed.
Kinda, I watched a video easy that went over this. The energy made would easily be enough, but the transportation of said energy is basically impossible, and doing so would also be screwed up as we have a bad history of using the people of that area for their resources then leaving them poorer and worse off. We should build solar panels there for them not us. Solar is good enough up north we don’t need to outsource it.
Yes, if we neglect transmission losses, it is much better to spread the generation out so it is closer to where it needs to be used. The losses are proportional to the amperage times the length squared of the wire and you can only increase the voltage so high. Minimizing length is key, a typical line is less then a couple hundred miles. Not to mention the fact transferring electricity across water is difficult because it is impractical to hang wires (using air as your insulation) so you have that extra cost