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Here's Elon Musk's Plan To Power the US on Solar Energy (inverse.com)
An anonymous reader shares an excerpt from Musk's keynote speech: Tesla CEO Elon Musk -- whose company makes electric cars and has a new solar roof panel division -- reminded more than 30 state governors at the National Governors Association meeting this weekend exactly how much real-estate is needed to make sure America can run totally on solar energy. "If you wanted to power the entire United States with solar panels, it would take a fairly small corner of Nevada or Texas or Utah; you only need about 100 miles by 100 miles of solar panels to power the entire United States," Musk said during his keynote conversation on Saturday at the event in Rhode Island. "The batteries you need to store the energy, so you have 24/7 power, is 1 mile by 1 mile. One square-mile." It's "a little square on the U.S. map, and then there's a little pixel inside there, and that's the size of the battery park that you need to support that. Real tiny."
I didn't do the maths myself beyond the back of a mental napkin, but these folks have http://blogs.ucl.ac.uk/energy/... and apparently the overall space checks out. Its far from the first time that similar scale claims have been made, and no, consolidating our entire solar grid into a single spot wouldn't make much sense from a security standpoint, but its interesting to think that we could get from here to there with no more (or less) effort for the country than, say, the Apollo program took.
You're special forces then? That's great! I just love your olympics!
Specifically, the cost part.
A quick google and a couple minutes with a calculator comes up with ~$1.5T for the solar panels, assuming sunny days all year round.
Plus the cost of the batteries, of course. And extra panels to cover rainy days.
And let's not forget the distribution system (which ranges from negligible to horrendous, depending on a lot of factors).
And the factories to build 50 billion or so solar panels.....
So, doable? Yeah, could be done. Cheap and easy? Not hardly.....
"I do not agree with what you say, but I will defend to the death your right to say it"
This plan will end up costing trillions and still will not work. It will also will cost trillions in grid improvements and probably tens of trillions in storage. I am sure Musk likes the idea of the US giving him trillions, but I think their are better and cheaper options.
Right. So you really think that if he spent all his own money, built it, and then went to the government and asked them to reimburse him...they'd say yes and foot the bill to the taxpayers?
They'd bitch. They'd moan. They'd form a few committees made out of people who don't know anything about solar, who invest in oil, or who think that the earth is going to end in the next century via divine intervention. Then they'd say they needed to observe the solar plant for a few years to verify it did what it was supposed to do. Then they'd offer to pay for 1/4 of the station on the condition that Musk builds a coal power plant for backup for the battery backup.
Yeah, can't imagine why he isn't going to "Build it first and trust in the government."
I prefer to look at production in terms of megawatt-hours-per-year-per-year. According to Wikipedia, the projected total PV output for the entire world was projected to be around 400,000 Megawatt-Hours this year
No.
The graph you link shows a production rate of 400,000 Megawatt (p) this year. Not Megawatt-hours.
Megawatt (p) = "peak Megawatt". One MW(p) of solar panels would produce 1 Megawatt under peak sun: that is, at noon, if placed normal to the noon sun. How many megawatt-hours you get from that many panels depends on how much sunlight they get (which depends on where they are, how cloudy it is, and what direction they are pointed).
Here's a map of the global insolation (short for "incident solar radiation", by the way) on a horizontal surface (which is not the optimum pointing for a solar panel): http://solargis.com/assets/gra...
Sunlight at noon is nominally 1 kW/m2, so the numbers on the top are effective hours of noon sunlight per year. Thus, if you put the panels horizontal at the "orange" regions of this map, you get about 2200 hours of sunlight. So: multiply your "Megawatts (p)" by 2200 to get Megawatt-hours.
http://www.geoffreylandis.com
Okay, let's do some Fermi math.
The US uses about 4 trillion kWh/year. https://en.wikipedia.org/wiki/...
But given a sufficient number of solar panels we only need to store enough for about 12 hours. 4 trillion / (365 * 2) = about 5.5 billion kWh, or 5.5 trillion Wh.
Watt hours to mAh is (Wh)*1000/(V) =(mAh): https://milliamps-watts.appspo...
The US generally uses 120 volts for power so that would be 45.6 trillion mAh.
I have on the desk in front of me a phone with a battery that holds about 3000 mAh and when stood on end takes up a surface area of about 618 mm^2.
45.6 trillion mAh / 3000 mAh/phone = 15.2 billion phones * 618 mm^2 = 9.4 trillion mm^2.
There are 1,000,000 mm^2 / m^2 so that would be 9.4 million m^2, and there are about 2.59 million meters per square mile, so 9.4 million / 2.59 million = 3.6 square miles.
So in order to get in down to one square mile you'd need a stack of phones four deep. This phone happens to be 129 mm high, so a stack of 4 would be 516 mm, or about 1 foot, 8 inches.
On the one hand you'd also need a lot of infrastucture to support those batteries which would also take up some area. However i'm also pretty sure that connecting over 15 billion phones in series would be far from the most efficient way to get the required battery storage.
I believe all that math works out?
This Space Intentionally Left Blank
Southern US border = 1989 miles (source)
100 miles x 100 miles = 10,000 sq miles (source)
Thickness of solar wall needed: 10,000sq miles / 1989 miles = 5.03 miles
Take this sig and smoke it.
Most of those [pumped-hydro] locations are already tapped.
For context, there's about 21 GW of pumped hydro capacity in the United States, which is about 1/5th of the capacity of all operating nuclear power plants in the US. But are most of those locations tapped?
No. I'll give you two general counterexamples.
1. One counterexample is the "west coast" of the lower peninsula of Michigan. There is one pumped hydro facility there, called Ludington. It's roughly 2 GW in capacity (with roughly 18 GWh in storage), and about 1000 acres in surface coverage. The lower reservoir is Lake Michigan; the upper reservoir is a man-made pond. But the geological features aren't unique to Ludington, MI -- it's prevalent on much of the lower peninsula's Lake Michigan coast, the result of dunes formed over millennia as debris blew west to east across Lake Michigan. Bottom line: there's no physical reason why one couldn't build a dozen facilities the scale of Luddington, also using Lake Michigan as a lower reservoir.
2. A second counterexample can be found at Taum Sauk mountain. The Taum Sauk Hydroelectric Power Station is a pumped hydro facility with 450 MW of capacity and 3,600 MWh of storage. The lower reservoir wasn't a pool of water at all until the facility was built; it was merely a fork of the Black River. The upper reservoir is an above ground swimming pool, built on top of the mountain. It's entirely man made. The geographic feature needed -- an elevation delta of a few hundred feet (860 in this case), with a slope common for forested mountainside, near a river -- isn't unique by a long shot.
That's two counterexamples off of the top of my head -- the Michigan coast of Lake Michigan and anywhere you've got a mountainous region with a river nearby. Plenty of technical potential.
The reason we don't have more pumped hydro is because the energy market price differential (LMP or system lambda, depending on region) between 3 am and 3 pm simply isn't large enough. It doesn't make economic sense to build more pumped hydro so long as we continue to burn coal and gas unabated, because the gap between the daily highs and lows aren't adequate. However, if we continue to retire coal and gas (and nuclear as it ages) and we continue to build solar PV, we'll see a flip where the peak price of energy drifts from early afternoon to 9 pm -- and storage will be economic, buying energy at 11am and selling it after sundown. Michigan could be the evening power center for the entire Midwest, and scattered new pumped hydro facilities on select Appalachian and Rocky terrain could easily store significant amounts of solar and wind output nearer the coasts.
Support a few technologists in Washington.
That's exactly the problem. Fossil fuels are not paying for the damage they do to health and the environment. They get to spew pollution and everybody else has to subsidize the damage.
Fossil fuels shouldn't be allowed to free ride on everyone else.
I don't read your sig. Why are you reading mine?
LOL.. That's from Tesla Power's PR campaign.
In case you haven't noticed, they haven't turned much of a profit yet and they are desperate to keep the stock price up to PE ratios that will make your nose bleed. They are just trying to forestall the inevitable stampede of sellers should it become apparent this whole idea isn't working out from the profit and loss perspective....Therefore, they and Tesla are hyping the stock (pump and dump kind of thing), which is what Musk is up to here. He's just trying to keep his fortune in Tesla Stock (that he couldn't sell if he wanted too) as high as he can, hoping beyond hope that eventually it turns a profit worthy of the stock price.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Every time I hear people speak of a carbon free future they will mention wind, solar, hydro, and geothermal but add the caveat of something like "with a little bit of nuclear" as if to try to please the entirety of the crowd.
Musk is doing the same in his talks, he'll say that solar would work to meet our energy needs. Of course he'd say that, he's a salesman trying to sell his products. I ask, how much would it cost? Not just in dollars but in lives.
According to this study the safest energy source we have is nuclear power.
https://www.nextbigfuture.com/...
According to the EIA nuclear is very low cost in dollars too.
https://en.wikipedia.org/wiki/...
I've had people dispute the numbers on nuclear power safety by claiming those numbers did not include large scale accidents like Chernobyl. As far as I can tell the numbers not only include Chernobyl but also expected reduced lifespan from the survivors. Chernobyl is also largely irrelevant, no one builds nuclear power like that any more and no one would be foolish enough to do so in the future.
People then tend to dispute the solar death numbers by claiming that trip and fall deaths "don't count" for some reason. These are still people dead from the construction and maintenance of solar power, even if it's because people failed to follow the safety rules and paid with their lives for it. By this metric we could say Chernobyl deaths "don't count" because they failed to adhere to proper safety protocols and many died as a result. Dead is dead, and if we are honest about the deaths then nuclear is much safer than even solar.
Then there is the carbon footprint, the whole reason we are having this discussion.
https://en.wikipedia.org/wiki/...
Nuclear power has nearly half the carbon output per energy produced than solar photovoltaic power. Concentrated solar thermal power has a lower carbon footprint than nuclear but that is not what Musk is selling, likely because those cannot be put on the roof of your house and because at current estimates it would cost double what PV does.
I look at the math and I found that Musk has it backwards. The future isn't solar "with a little bit of nuclear", it's nuclear with a little bit of solar.
I am armed because I am free. I am free because I am armed.