# Surface area required to power the world with solar panels...

Discussion in 'Off Topic' started by sparky, Aug 31, 2009.

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2. ### loquinActive Member

10000 square miles. 30.976 billion square yards

25921 square km. 25.921 billion square meters

for the solar cells, at today's prices, (\$200/half a square yard) it's about 6 trillion dollars. But, you've got to throw in storage capacity. And, you have to install the solar panels. Add the infrastructure to get the power out. You're probably looking at 20 trillion or so. Give or take a few trillion.

At these volumes, though, it's more efficient to use other technology - use curved reflectors to use the sun to heat oil, or other liquid with a high heat capacity, pump the hot liquid through boilers, and then use the steam to turn turbines. The cost would be less, and you're using 'standard' technology for the power generation.

3. ### sparkyActive Member

OK... I tried my best, tho I couldn't get too much information based on cost per surface area... most places tell you cost per Watt.

Anyway, one site said that a 1 sq in. PV cell would create 45 mW of power. Multiply that by 63360 squared (in. in a mi.) * 100 squared (mi. squared we need of panels) = 1 806 520 320 000 000 mW = 1 806 520 320 000 W

OK.. so 1.806 teraWatts a day sounds pretty close to me. Another website said that \$7 per Watt would be accurate, so 1 806 520 320 000 W * \$7 = \$12.646 Trillion.

Can you believe that?!? For the amount of bailout money we wasted, the entire U.S. coulda been completely solar powered in 10 years. Which idea would you have spent money on -- energy independence or reckless banks, insurance companies, and gov't??

4. ### sparkyActive Member

Yea... I figured "real" cells would actually be cheaper than using a 1 sq in. cell. Half the cost is a huge difference.

And, of course, I forgot to take into account batteries and installation..

I wonder if hydrogen fuel cells could be used to store energy more efficiently and/or economically than batteries.

Last edited: Sep 1, 2009
5. ### machiasmortActive Member

If I was Republican, I would have chose reckless banks because I'd get Kick backs!

Seriously though, I can't see why they don't float pannels on giant rafts. That would be our biggest bennefit to end global warming. Provide the Ocean some shade!

6. ### SimpleSimonActive Member

You've also neglected the cost of buying 10,000 sq miles of land, and ignored the cost of infrastructure to install, maintain, and replace storm damaged or failed panels. You do realize that dust accumulating on their surfaces significantly degrades their performance, right? Not too mention, the electricity that would be required to produce those panels, as well as the cost of obtaining and cleaning the sand that goes into the furnaces that make the glass, etc.

"Pie in the Sky" guesstimates of total production in dreams against actual production in reality ALWAYS neglect those factors that really drive costs. Such as, labor to build all of the infrastructure and maintain it, plus the asphalt for the roads needed, the steel and aluminum and copper that go into the support structures and power conduction leads, along with everything else.

Triple your initial cost figures and you might get in the ballpark of the REAL cost upfront - then add in about 10% of that cost as an annual budget for operation.

7. ### sparkyActive Member

There's ways you could work around the 10,000 sq mi of land, tho.

Like mort said... float 'em out in the ocean. Or you could just ask if anybody wants free power for the rest of their life for sparing some of their roof space. Or you could offer a little compensation for someone sparing you some of their unused land. Or we could build some indestructible PV cells that we could drive on and put 'em on the roads. That would be too easy if we could do that.

As for costs, those are for costs today. If a project like this was undertaken... the scale of the project alone would decrease the estimated costs for the product itself. Then when business folks & mainly investors see this, they get serious about making things more efficient so that they'll possibly be able to get a Gubmint contract the next year. Competition in the solar industry would get serious... and then costs would decrease and less land would be necessary.

Sure maintenance would be a problem, but with decreasing pollution, better efficiency & growth in the solar industry, more jobs, and eventually smaller electric bills... it's a no-brainer. EVERYBODY wins from that, whereas hardly anybody wins from the bailouts.

8. ### machiasmortActive Member

Republicans are working with Harbor Freight on a volume price deal for the pannels and wire... In the mean time they ordered 100,000 feather dusters from Tiwan so the Mexicans don't ruin their shirts (doing jobs Americans don't want to do), dusting the glass.

Really tho, how about floating these things to cool the Ocean!

9. ### biketecMember

What if it was mandatory all new houses built in 2010 and beyond must have solar panels covering at least 3/4 of the roof the other 1/4 could be allocated personal or expansion??? Or we could just use the freshly burnt LA??? and then like he said 99.9% of it would still have a job washing the glass??? and the homes could be built under it????

10. ### machiasmortActive Member

Eeeh, Cockroach footprints on glass, worse than sand!

11. ### arceeguyActive Member

Sparky - to distribute electrical power efficiently, current power plants produce AC. PV panels produce DC power, which would have to be converted to AC (incurring losses and major expense) for distribution. If Edison had his way, our power distribution would be DC (he thought it was safer than AC) and power plants would be spaced only several miles apart.

PV panels are useful if we start to decentralize the power grid so that each home is its own little "island".

12. ### give me vtecActive Member

SS always seem a moderate voice of reason...

How do you feel about those sun towers in Spain?

13. ### SimpleSimonActive Member

Solar concentrators are not new at all. There is the (possibly apocraphyl) claim that an ancient Greek army used polished bronze shields to focus reflected sunlight upon an invading fleet, burning it before it could land. In the 1960's the French government built a "sun tower" generation station in the south of France, and there have been many much smaller implementations of the idea as well.

As installed commercially they are useful where one can reliably depend on clear skies 80% of the daylight hours or more. There are drawbacks, as with any technology, such as the relatively high labor investment required to build, install, clean and maintain the large number of heliostatic mirrors and their drivers involved. Once installed, they are of course "carbon neutral", but no analysis I've seen addresses the "carbon cost" of building them.

Mother Earth News designed and built a backyard version of this idea in the late 1970's - it used 1 foot square mirror tiles mounted on adjustable wire supports in a 10 x 10 array, giving a 100 sq ft concentrator surface. Each individual mirror was aimed at the boiler, which rose on a mast above the upper edge of the encompassing solar tracker frame - the entire array followed the sun across the sky as a unit instead of each mirror individually.

It worked, but given their research centers location in North Carolina, was not hugely effective. Tracking mechanisms, to be effective, require a two axis controlled variable angle - they not only pivot to follow the suns path on a given day, but must pivot on the perpendicular axis by a small increment to track the suns changing angle of incidence throughout the year.

eSolart's twin tower solar concentrator steam generator plant went online in Lancaster, CA last month. It's a 5 MW power plant - roughly equivalent to a single conventional nuclear reactor - but it only works an average of 1/2 of each dau, obviously. The mirror array is huge - there are 12,000 mirrors of roughly 10 sq meters each surface area in it - and once again, nothing I have found addresses the operational costs of cleaning and maintaining that mirror surface and the individual tracker mechanisms.

Do not mistake that as being critical of the idea or its implementation - it is NOT so intended. I just wish for more openness and honesty by proponents of any "technological fix".

I want somebody to build a "wind tower". Which is simplicity itself in concept, and can potentially run 24/7, generating relatively huge amounts of power from a much smaller footprint.

Last edited: Sep 3, 2009
14. ### sparkyActive Member

SimpleSimon, have you ever written a book before?? If you haven't, have you ever considered writing a book before?

I only ask, because I'd be willing to pay AT LEAST \$25 for a book of all your "technological fixes"... prolly even more. I paid 25 cents for George Carlin's When Will Jesus Bring The Pork Chops? at the thrift store (which was actually very good, btw), and I'm sure your no-BS technical knowledge is worth at least 100 times more than that. How about \$0.25 a page?!?

15. ### SimpleSimonActive Member

Yes, Sparky, I've written a book before. Several of them, actually.

None of which are publically available, nor is the curriculum guide, or the syllabus or any of the training materials I wrote. I have a book in progress right now, which is a semi-autobiographical series of stories about dogs (and other animals) I knew growing up. Had a publisher lined up, but the senior editor I was working with had a massive heart attack and had to retire - the lady who took over his slot isn't as fond of my stories as he is.

Thirty years ago I had a dozen stories published in three different magazines - none have ever been anthologized. I did all of my non-technical writing using several different pseudonyms, and those remain my business to know.

I also have two different collaborations in progress, one an SF novel with a fairly well-known author, the other a mystery with a newcomer.

My technological info is all already out there (except a bit of proprietary DNA sequencing methodology), and honestly, anyone interested can find answers to their questions such as have been raised here quite readily on the web.

So, thanks for the flattery, but honestly, the subject matter you raised is covered well by Home Power magazine and other sources.

16. ### loquinActive Member

The sun is responsible for most of the wind on the earth, so, tapping wind power is just another (indirect) means of tapping the sun...

17. ### SimpleSimonActive Member

Absolutely true.

The differences and the justifications for tapping wind power are mostly technological systems questions.

18. ### sparkyActive Member

I dunno, tho... I'd kill for a book where you acted as Dictator of America and put all your technical knowledge into action. Energy, transportation, etc... I know I've seen you mention several contraptions before that just seem so damm obvious. A book of SimpleSimon's many solutions to real problems would make for great reading, I'm sure.

19. ### machiasmortActive Member

He's really not that smart Sparky... He just copy cuts and pastes here,(from the internet).

Many people have poked fun about my saving older pennies... I know it sounds funny. Just a quick note and on topic, Copper is being consumed like crazy (making solar pannels) adding to it's value!

Easy Simon, I'm only joking! LOL! He does come up with some wild stuff!

Without getting way over my head! What's your knowledge on the way photons react in a solar pannel inorder to create current?

20. ### machiasmortActive Member

And thats why I'm 100% behind it! Gubmint don't want us independant. They want tax money and control of your house!