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Businesses Power The Almighty Buck United States

Here's Elon Musk's Plan To Power the US on Solar Energy (inverse.com) 507

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."
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Here's Elon Musk's Plan To Power the US on Solar Energy

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  • Double Checking (Score:5, Interesting)

    by rjstanford ( 69735 ) on Monday July 17, 2017 @04:07PM (#54827973) Homepage Journal

    I didn't do the maths myself beyond the back of a mental napkin, but these folks have http://blogs.ucl.ac.uk/energy/... [ucl.ac.uk] 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.

    • Re:Double Checking (Score:5, Informative)

      by SYSS Mouse ( 694626 ) on Monday July 17, 2017 @04:15PM (#54828033) Homepage

      He said the space needed. It does not have to be in the same area.

      • by gnick ( 1211984 ) on Monday July 17, 2017 @04:22PM (#54828079) Homepage

        It won't be in the same area. Not once we have our solar-powered, transparent border wall. How many square miles is that?

        • by fahrbot-bot ( 874524 ) on Monday July 17, 2017 @04:28PM (#54828125)

          It won't be in the same area. Not once we have our solar-powered, transparent border wall.

          Ya, but the Sun is overhead and walls are vertical so we'll have to tip the whole planet to get maximum efficiency. That will be a huge PITA with stuff sliding around, rolling off tables and such.

        • Re: (Score:3, Funny)

          by cayenne8 ( 626475 )

          It won't be in the same area. Not once we have our solar-powered, transparent border wall. How many square miles is that?

          It would be cool to have a solar powered ELECTRIC fence on the border....fry anyone that tries to cross illegally.

          Instant fajitas!!!

          ;)

          • by skids ( 119237 )

            I thought that was the point, given how useless it would otherwise be to put a bunch of panels out where they have no security and a really long run along a daisy chain of distribution wires. Oh hey look all the houses south of the border installed new solar panels... hey those panels look familiar... come to think of it, that used copper wire we just bought off the scrap dealer looks familiar too...

            Or maybe Trump just wants it to light up at night so it will be visible from space.

            I'm still pulling for pot

        • by rtb61 ( 674572 )

          How about you take the area of all existing roofs and make it law, that all roofing material in the future has to have solar panels incorporated in it. The total area of the burbs on their own would probably do it and fit them with larger batteries and you have an extended shared, electrical grid. That would also feed power to a larger centralised storage system. A power company could run around and offer to replace peoples roofs with solar panel roofs, supplied at a huge discount with all generated current

    • by mysidia ( 191772 )

      and no, consolidating our entire solar grid into a single spot wouldn't make much sense from a security standpoint

      So instead of having 1 10000 Mi^2 site.... have 10000 1x1 Mi^2 sites....
      or better yet 185,853,333 sites that are 1500 Square-Ft of panels each.

      Just make sure they are all well-distributed across the grid and hardened, so they are not easily damaged by weather conditions, and not easily harmed by remote electrical attacks.

      • Elon's always been a fencing scar and Persian cat from being a true Bond villain.

        Obviously he's going to use SpaceX as a means to loft a NAZI Sun Gun [wikipedia.org] to bend the world to his will.
        I mean with those resources, he'd have to be STUPID to not go the SSPS / superweapon route.


        Posting this logged in so you know why when I go missing...
    • The math for the solar array is certainly in the ballpark.

      For the battery? Who the hell knows? You probably need a pdf (No, not that kind of pdf -- a Probability Distribution Function.) for sunshine and a specification for how many days, hours, minutes, seconds a year of outage can be tolerated in order to spec out the battery. I'm skeptical that one square mile of "battery" is adequate.

      Or maybe you need a full, rarely used, backup generation facility (generating power from what?) for periods when the su

    • Actually, it doesn't completely add up, for a couple of reasons.

      First, Musk is (semi-purposely?) conflating the area required to generate the same amount of electricity that the US uses each year with the amount of energy that the US uses. Second, he's talking about the square footage of panels, not the square footage of any reasonably designed panel array (multiply that number by 4).

      The late physicist David MacKay, an adviser to the UK's Department of Energy and Climate Change and author of the great "Sust

      • Re:Double Checking (Score:4, Interesting)

        by Enigma2175 ( 179646 ) on Monday July 17, 2017 @11:57PM (#54830557) Homepage Journal

        First, we need to drop our average per capita energy usage from 250 kWh/day to 125 kWh/day.

        That number seems wrong. I looked at his website (the design is Geocities, circa 1998 - nice!) and it's not immediately obvious where that number came from, but it appears to be too high. In 2015 the US generated 4,077.6 TWh of electricity so that's around 35 kWh per capita per day. That year 3.22 trillion miles were driven, if everyone magically had a Telsa Model S (which uses 340 wh/mi, smack dab in the middle in efficiency for electric cars listed by the EPA [fueleconomy.gov]) instead of their current car that would be another 9.3 KWh per day per capita.

        So that's around 45 kWh for electricity and transportation, where does the other 205 kWh come from? Heating? The electricity number already includes all the electric heating (as well as commercial and industrial use) so it would just be oil and natural gas - do those really add up to 205 kWh? We used 27.3 trillion cubic feet of natural gas, but a ton of that is already included in the electric number. According to the EIA [eia.gov] it was closer to 15 trillion for residential, commercial and industrial use. That would be another 38 kWh. We burned around 390 billion gallons of heating oil, that's another 1.5 kWh. I don't necessarily think that converting the total heat available in those substances to kWh is a valid comparison but let's ignore that for now. We are still only to 84 kWh per person per day, where is the missing 166 kWh?

        Looking further on his site I think I see what the issue is. He just makes up numbers and then adds those to his total. For example, on this page [withouthotair.com] he guesses at a number for kWh per airline passenger and then rather than using data like actual miles flown he just assumes every person makes exactly one intercontinental trip (from London to Cape Town) per year and extrapolates a 30 kWh usage for that. He does similar things throughout the site, instead of using actual consumption data he makes estimates based on broad assumptions. I'm sure he has interesting things to say but there's certainly no rigor in his numbers and it's a poor site on which to base a numbers post.

        • That's the problem with skimming the book, looking for reasons to doubt it.

          The section you linked to was part of the "technical chapters" that was explaining how to convert a "long distance" flight to standard units of energy, and then to contrast that with the amount of electrical energy that would need to be generated. He has several such chapters on various bits (cars, wind generation, etc) and will use them as examples of a potential "stack" of energy use or generation.

          But when he talks about actual usa

          • But that number is a double conversion again, they convert all energy usage in the UK to "oil equivalent units" and then he then converts that amount of oil to kWh instead of using actual electricity and oil consumption numbers. I'm not paying $500 to the UN [un.org] to view their statistics, but if their methodology for the US is also to convert all energy usage to oil I don't think it's a valid comparison.

      • Those numbers don't really make sense.
        Half the coast of Florida with offshore wind farms would be enough to cover USAs current energy needs several times over. So as "back up" you put the smae at the coast of Oregon and thats it ...

    • Re:Double Checking (Score:5, Interesting)

      by Maury Markowitz ( 452832 ) on Monday July 17, 2017 @05:49PM (#54828823) Homepage

      It is worth putting this into perspective:

      The US has about 16 million hectares of pavement.

      100 by 100 miles is about 2.6 million hectares.

      • Wikipedia: the average area of a US Walmart is about 10,000 square meters (~100,000 square feet)
        Statista: There are about 5000 Walmart stores (and affilliates) in the US.

        Total area: about 0.2% of what you need to get 100 miles by 100 miles.

        I'm pro solar, but the scale of going 100% solar is not small.

  • by the_skywise ( 189793 ) on Monday July 17, 2017 @04:07PM (#54827975)
    One square mile of batteries Is all that's needed to store the energy for the entire US?

    Color me skeptical.
    (fine print: it's a 200 story building)
    • One square mile of batteries Is all that's needed to store the energy for the entire US?

      Nah, just to store enough to cover the dips in solar production - although I'd think that lake storage would be easier. Then again I'm not an expert by any stretch of the imagination, and Musk is (although he's also biased in that he does own a pretty big battery company) :)

      • by jandrese ( 485 )
        Dips in solar production like that 8-16 hour period when the sun is below the horizon? Especially in winter when the days are short and people are heating their home with electric?

        Going all battery is probably the wrong solution. Stored hydropower and other such systems will probably need to be part of the plan.
        • Especially in winter when the days are short and people are heating their home with electric?

          Hmm...we use gas for heating and cooking here...

          Of course, it never gets that cold here, but I surely NEVER want to give up my gas range for electric....ugh, that is NO way to cook (electric).

    • That was a weird point. Anything can be 1 square mile in area as long as you are willing to go high enough.

      Is Mr. Musk talking about a building ten feet high (roughly one storey) or 1,000? In either case, they only take up one square mile.

    • Re:ONE SQUARE MILE?! (Score:5, Informative)

      by Daetrin ( 576516 ) on Monday July 17, 2017 @05:13PM (#54828541)
      Okay, let's do some Fermi math.

      The US uses about 4 trillion kWh/year. https://en.wikipedia.org/wiki/... [wikipedia.org]

      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... [appspot.com]

      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?
      • 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.

        The 3,000 mAh is at 3.4v so 3.4v/120v * 3,000mah = 85 mah / phone

        45.6 Trillion mAh / 85 mAh * 620mm^2 = 128 square miles 1 phone deep. If we assume that we can build up 6 feet that would be 14 phones high. 128 square miles / 14 = 9 square miles.

        So clearly Elon Musk is assuming a lower power demand during the 9. Which I think is a safe assumption since we arguably are fast asleep for 8 of the 12 hours. If we use full power for 4 hours and no power once we're asleep (both bad assumptions) then you're

      • Your phone doesn't have a 120 volt battery, so you can't compare mAh between your hypothetical battery bank and your "1 phone" unit. Better just to keep the phone battery capacity in Wh, your 3000 mAh battery is nominally 3.7 volts so it holds 11.1 Wh. By your calculation you need 5.5 trillion Wh so you will need in the neighborhood of 495.5 billion phones instead of the 15.2 billion you calculated.

        A better comparison would be Tesla powerwalls, since that is probably what Elon used in his calculations. T

    • So a better way to put it is that it is order of one CUBIC mile. You can make the cross-section smaller by making the stack higher or vice versa. Area measures make sense for solar cells. They don't for batteries.

      They REALLY don't for batteries that are supposed to back the whole solar grid for the US. Those batteries generate heat as they operate -- charging or discharging. If you actually built a solid battery a cubic mile in volume (say) heat losses scale like the outer radiating surface, heat p

  • by CrimsonAvenger ( 580665 ) on Monday July 17, 2017 @04:17PM (#54828057)

    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.....

    • by RobinH ( 124750 ) on Monday July 17, 2017 @04:28PM (#54828123) Homepage

      So, doable? Yeah, could be done. Cheap and easy? Not hardly.....

      I think that's how I remember it... "Ask not what your country can do for you, because we only do what's cheap and easy." Must be the new American anthem.

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      Specifically, the cost part.

      A quick google and a couple minutes with a calculator comes up with ~$1.5T for the solar panels,

      more quick googling:

      Total electric company revenues from sales to ultimate customers equaled $381 billion

      so in other words it's only four years of revenue to totally replace the system

    • by b0bby ( 201198 ) on Monday July 17, 2017 @04:31PM (#54828163)

      ~$1.5T for the solar panels

      If you think of that as less than 2 years of the US military budget, for hardware which could last 20+ years, that actually doesn't sound so bad.

      I imagine the batteries would be really expensive right now though.

    • Specifically, the cost part. ... ~$1.5T for the solar panels, ... Plus the cost of the batteries, ...

      No problem. We get Chinese made parts via Amazon Prime -- or Walmart -- and use a rewards or cash-back CC.

    • Either way, after we do it, you'll be able to see Musk's bank account from orbit.
    • by pr0t0 ( 216378 )

      Only doing what's cheap and easy is for unethical lazy cowards.

      The $1.5T is no small amount, but what do you compare it to? Depending on where Google takes you, the US spends between $300-600B on energy infrastructure. We also spend $100-150B on costs associated with air pollution. That's just two cost vectors accounting for nearly 1/3 to 1/2 of your guesstimate of Mr. Musk's plan, and that's almost certainly not all of the costs associated with our current infrastructure. And those are ANNUAL costs. I bet

    • 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.

      That cheap???? The U.S. spends 1.2 Trillion dollars on electricity per year. You could make enough panels to power the whole U.S with just the money we spend on electricity in 15 months?

      Go for it!

      Plus the cost of the batteries, of course. And extra panels to cover rainy days......

      OK, slightly more.

      Seems like a bargain, though

      • 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.

        That cheap???? The U.S. spends 1.2 Trillion dollars on electricity per year.

        oops, my google-fu failed me. 1.2 Trillion is the amount we spend on all energy per year, not just electricity. Electricity is about 31 percent of that.

        Still, you're saying that four years of the money we spend on electricity would pay for the panels? Still sounds like a bargain.

    • 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.

      Fossil fuel subsidies cost the globe $5 Trillion each year [scientificamerican.com]. So by that standard your number seems downright reasonable and cost effective.

      So, doable? Yeah, could be done. Cheap and easy? Not hardly.....

      Nobody said it would be cheap but it might easily be cheaper than all of the alternatives. Certainly will be cheaper than fossil fuels and the baggage they bring.

  • by atomicalgebra ( 4566883 ) on Monday July 17, 2017 @04:23PM (#54828099)
    Solar has a very low capacity factor (~20%-30%) which means we need to find a way to store the electricity. The majority of storage is done thru pumped-hydro. Most of those locations are already tapped. Batteries won't solve it either. Tesla's gigafactory is not going to be able to produce enough batteries for grid level storage. Current storage can be counted in the minutes, but we will need several weeks of storage to make this plan viable.

    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.

    • I can't see Li+ cells being practical for an application of this magnitude. Too expensive.
      Flow battery technology on the other hand is designed to be cheaply and easily scalable, if I'm not totally mistaken. The energy density isn't anywhere near as high, true, so maybe it's a few square miles (of land nobody wants anyway, right?) instead of just one square mile, so what?

      Of course as I stated elsewhere, I'd be uncomfortable with having 'all our (energy) eggs in one basket' like this. Spread out over, sa
    • Tesla's gigafactory is not going to be able to produce enough batteries for grid level storage.

      A single factory is not intended to. But Tesla projects that 100 gigafactories would meet demand for 100% world-wide renewable energy. [futurism.com]

      Is it expensive? Yes. But so is the current power industry. If cheaper options exist for sustainable energy storage (as you suggest) then they will eventually prevail against current options. But pumped hydro is mostly played out (and hydro usually causes massive habitat destructio

    • Solar has a very low capacity factor (~20%-30%) which means we need to find a way to store the electricity.

      We have that and we're making it better fast. Batteries are already available at reasonable price points and the cost is falling steadily.

      The majority of storage is done thru pumped-hydro.

      Some is but that's going to change as solar and becomes more popular. You'll see homes and businesses with battery packs in steadily increasing numbers in the coming decades. It's already cheap enough that I can buy a battery pack to power my home for an entire day for under $10K and the price keeps falling.

      Tesla's gigafactory is not going to be able to produce enough batteries for grid level storage.

      Why do you presume it will be the only factory producing batte

    • by stomv ( 80392 ) on Monday July 17, 2017 @05:38PM (#54828745) Homepage
      ... including yours. I'm referring specifically to:

      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.

  • I definitely favour replacing all fossil and nuclear power generation with renewable energy sources including solar, wind, tidal and geothermal. However, in the case of solar energy, can anyone estimate the potential impact on the environment of fabricating a square mile of say lithium-ion batteries? how much lithium would that require? What amount of the earth's crust would we have to mine in order to get it?

    Similarly, with a solar array of Musk's proposed 10,000 square miles, what would the rate of rep
  • A 10,000 square mile solar array? Difficult to attack/sabotage/cripple, just due to sheer size.
    A 1 square mile electric energy storage farm? Easier to attack. That's what I'd be afraid of.
    • you don't have to put all one square mile of storage in one place, for example have 9 places a third of a mile on each side.....there is no problem

  • that's the size of the battery park that you need to support that. Real tiny."

    and real easy to target

    So apart from the obvious reasons for not doing this - the weather, you also have to consider resilience, counter-terrorism, not having all your wires in one basket.

    And on top, the requirement for electricity will always keep growing. So that 1 sq. mile will become 2 (especially when everyone has an electric car). And while the batteries may only take up a square mile, how much space will the industrial slag from their manufacture take up?

    • by Socguy ( 933973 )
      Musk was only pointing out how much space would be needed to help the Governors visualize that it's very doable. I don't see anyone actually suggesting that we carve out a 100X100 square of the US and actually do it. It makes far more sense to spread them across the continent, if for no other reason than you reduce the need for power transmission lines and you spread your peak generation times out according to your time zone. Throw in wind and hydro and the problem is licked.
  • by Mysticalfruit ( 533341 ) on Monday July 17, 2017 @04:41PM (#54828253) Homepage Journal
    As cool as all that is, I still think the better solution is to have every roof covered with panels and have local / neighborhood battery storage.
    • if you lived in Arizona, that would be great. Where I am, you'd get maybe a quarter to third of the power you'd normally want to use, and that might not be a bad thing at the lower prices that are coming. But what you're proposing is a more a backup or emergency strategy for over half the county.

      • if you lived in Arizona, that would be great. Where I am, you'd get maybe a quarter to third of the power you'd normally want to use, and that might not be a bad thing at the lower prices that are coming. But what you're proposing is a more a backup or emergency strategy for over half the county.

        Not at all. Stop it with the claim that a solution has to be perfect in every respect to be worth doing. Even if rooftop solar doesn't cover 100% of your energy needs it still is a fantastic idea and certainly is more than a backup/emergency idea. I've already done the math and with current technology I could be net zero or better to the grid with my house if I had a solar covered roof and I live in a northern state not noted for intense sun. I'm hardly the only one in that situation. Roofs are nothing

  • 100 hundred years of US garbage will need a landfill 100 ft high, and 18 miles on each side.

    People lose their minds over the landfill "problem", so it seems Mr. Musk is going to have a hard time convincing them to switch to solar.

  • When all you have is a hammer, everything starts to look like a nail...
  • He is not the first one to suggest using solar powers closer to the equator to power the northern hemisphere. The problem is that once you generated that power, you need some way transport it to where it's needed. There are some more detailed concepts [wikipedia.org] based on HVDC, but that's still fairly new and unproven tech.

  • by sjbe ( 173966 ) on Monday July 17, 2017 @04:58PM (#54828425)

    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,"

    We've easily got that much space sitting mostly unused on roofs. Even better it's already right where we need most of the electricity. Obviously Musk and Co are already well aware of this fact. It just requires an investment horizon longer than the end of your nose.

  • 2 birds, 1 stone? (Score:5, Interesting)

    by Darth Twon ( 2832799 ) on Monday July 17, 2017 @05:15PM (#54828553)

    Southern US border = 1989 miles (source [wikipedia.org])
    100 miles x 100 miles = 10,000 sq miles (source [lmgtfy.com])

    Thickness of solar wall needed: 10,000sq miles / 1989 miles = 5.03 miles

  • of solar panels. Practically nothing!

  • I've never understood why people always talk about using such a big area. For years where I'm at new apartment buildings are required to have cable connectors. Because cable is considered a 'utility'. Well, so is electricity. So why not require them to have solar panels and batteries as well? Most apartments have utilities included in the rent anyway. So in the long run the owner is going to save money. The builders would probably scream, "It's a burden!" which is what they did when they were forced to ad
  • by pz ( 113803 ) on Monday July 17, 2017 @06:22PM (#54829053) Journal

    Many of these analyses are missing a basic, fundamental point and variations on that point: You don't have to do the full monty to get improvements.

    1. Even if you only have solar farms and no batteries, that reduces the dependency on fossil fuel. For certain parts of the country, the times of maximum insolation correspond really quite well with maximum usage due to cooling and business / manufacturing needs, so no batteries needed, and the existing generating capacity can be scaled back to cover nights and days with less sun.

    2. Battery capacity can be phased in (a corollary to point 1) and the system will still be useful.

    3. Just because you can't do it all immediately and POOF have a sudden switchover to full solar doesn't mean it isn't a laudable goal to work in that direction. Moreover, because it will disrupt a fair chunk of the economy to switch over to solar, doing it gradually (on the scale of decades) makes sense.

    4. Even if the goal is only to achieve 10% replacement of existing fuel-based generating capacity with solar, it's a good thing to do.

    5. Our existing nuclear power plants have a finite lifetime and replacement capacity will need to come from somewhere.

    6. Just because solar power doesn't make as much sense in certain parts of the country (primarily the more northern lattitudes) doesn't mean there is no value to deploying it where it does make sense.

    7. Tesla is a battery manufacturer (among other things); chemical batteries aren't the only way to go for storage. Lithium batteries in particular might not even be a good way to go, given their limited lifetime and potential to catch fire as a failure mechanism.

    8. Batteries alone (or some storage technology) without any solar power might be a good idea to allow scaling-back of peak generating capacity.

    So, a national effort to improve the power infrastructure just might be a good idea, even if it isn't quite the pipe dream from the summary.

  • by blindseer ( 891256 ) <blindseer.earthlink@net> on Monday July 17, 2017 @09:30PM (#54829957)

    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/... [nextbigfuture.com]

    According to the EIA nuclear is very low cost in dollars too.
    https://en.wikipedia.org/wiki/... [wikipedia.org]

    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/... [wikipedia.org]

    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 have hardly ever known a mathematician who was capable of reasoning. -- Plato

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