[HN Gopher] US Army deploys its first floating solar array
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       US Army deploys its first floating solar array
        
       Author : imartin2k
       Score  : 168 points
       Date   : 2022-06-15 07:29 UTC (2 days ago)
        
 (HTM) web link (www.theverge.com)
 (TXT) w3m dump (www.theverge.com)
        
       | spamizbad wrote:
       | Seems aligned with General Pershing's vision of "Infantry wins
       | battles, logistics wins wars."
       | 
       | Having a source of electricity that doesn't require diesel fuel
       | can be advantageous. It's silent, with a lower heat signature
       | too.
        
         | ryanmarsh wrote:
         | I appreciate the sentiment but this is a permanent installation
         | for a US base in North Carolina. Also there is nothing tactical
         | about a solar farm.
         | 
         | JP-8 (similar to diesel) is easy to source the world over, has
         | high energy density, is easy to transport and runs nearly
         | everything in the military.
         | 
         | Solar is a nice idea but we're nowhere near (economical) panel
         | efficiencies necessary to transition field electricity use.
         | Keep in mind, the further you get from the flag pole the less
         | electricity you need. Things are designed that way for obvious
         | reasons.
        
           | codyb wrote:
           | Wouldn't the early iterations of something generally be
           | pretty lame?
           | 
           | Seems possible in 50 years or so things could be more mobile
           | or advanced in other manners.
           | 
           | Either way, certainly interested in seeing what the USAF will
           | be doing to get to 0 emissions. I have a sense they may be
           | able to harness resources towards goal a bit more effectively
           | than some of our more fractured systems of governance.
        
             | nine_k wrote:
             | USAF can go carbon-neutral by sourcing synthetic fuel.
             | Zero-emission, never.
        
               | ncmncm wrote:
               | Emitting only water vapor is well within foreseeable
               | development. Would provide better range, besides.
        
             | bequanna wrote:
             | Only if you can also make energy storage super small and
             | portable for those times when the sun isn't shining.
             | 
             | Seems easier to invest in micro reactors.
        
           | wffurr wrote:
           | Only thing even close for energy density and thus potentially
           | useful for logistics would be a small modular reactor, which
           | could then be used to create diesel on site. Trucking the
           | reactor in though has obvious security concerns.
        
           | chrisco255 wrote:
           | Sun does not even produce enough watts per square meter to be
           | practical for transportation of heavy artillery (nevermind
           | that it produces zero at night). It's ridiculous to imply
           | solar ever has potential beyond supplemental energy.
        
         | nomel wrote:
         | > with a lower heat signature too
         | 
         | The visibility will be extreme though, for the same energy
         | density. If mobility is a concern, then the energy density/lb
         | would be incredibly low, compared to fuel. I think this would
         | only make sense if you were near a body of water (obviously)
         | for an extended period of time, and you didn't care if everyone
         | flying over knew you were there.
        
         | newsclues wrote:
         | What happens when someone airbursts munitions over your solar
         | farm?
        
           | antisthenes wrote:
           | Nothing much, as compared to someone potentially shelling a
           | nuclear power plant or a diesel fuel depot.
           | 
           | Besides, solar panels are so cheap these days, that it might
           | cost more to destroy them with munitions than to
           | install/purchase them in bulk.
        
             | goodpoint wrote:
             | Indeed. Of all energy sources, solar and wind are some of
             | the safest in case of war, terrorism and social unrest.
             | 
             | Nuclear, gas, oil... not so much! Same for dams.
             | 
             | And even if you avoid immediate loss of life and
             | environmental damage you still have an emergency to handle.
        
             | ncmncm wrote:
             | An EMP is cheap to generate and could take out a whole
             | array.
        
           | halJordan wrote:
           | Good question, you can fill out the draw; just have it done
           | before you leave today.
        
       | imwillofficial wrote:
       | I wondering what the effects are to the flora and fauna in a
       | setup like this.
        
         | schimmy_changa wrote:
         | It's an area of open research, but especially if it doesn't
         | cover 100% of the water body it's fairly benign:
         | https://www.sciencedirect.com/science/article/pii/S136403212...
         | 
         | For instance, birds perch on the panels, turtles loaf on the
         | floats, fish hide from predators under them. It changes the
         | water body, but not in a way that would be different from, say,
         | trees that have fallen halfway into the water and are shading
         | part of the surface.
        
       | yumraj wrote:
       | What happens to the plant/animal life under these floating solar
       | arrays?
        
         | schimmy_changa wrote:
         | It's an area of open research, but especially if it doesn't
         | cover 100% of the water body it's fairly benign:
         | https://www.sciencedirect.com/science/article/pii/S136403212...
         | 
         | For instance, birds perch on the panels, turtles loaf on the
         | floats, fish hide from predators under them. It changes the
         | water body, but not in a way that would be different from, say,
         | trees that have fallen halfway into the water and are shading
         | part of the surface.
        
       | mateo1 wrote:
        
       | ch4s3 wrote:
       | I wonder if floating PV would be an interesting alternative to
       | the shade balls used in some reservoirs[1]? You could get the
       | benefit of lowered evaporation and some extra pv real-estate.
       | Maybe the math is favorable, maybe not.
       | 
       | [1] https://en.wikipedia.org/wiki/Shade_balls
        
         | dokem wrote:
         | I don't see the goals overlapping other than the fact that they
         | both float. The solar panels will cost 1000x that of rubber
         | balls, and the cost of repair/maintenance of floating panels
         | will be much higher than land mounted panels. There may be some
         | circumstances where you can kill two birds but I bet it's rare.
        
           | ncmncm wrote:
           | Balls generate zero revenue. Solar arrays generate net
           | revenue.
        
           | ch4s3 wrote:
           | As the sibling points out, canals seem like a good place to
           | shade water with solar, though probably not floating.
        
             | ncmncm wrote:
             | Floating is overwhelmingly better, because cold panels are
             | more efficient than dry ones.
        
         | 7952 wrote:
         | Water companies tend to use a lot of energy which is a major
         | cost for them. That is the math that is going to be most
         | significant.
        
         | schimmy_changa wrote:
         | Yes! Check out the Healdsburg project:
         | https://www.northbaybusinessjournal.com/article/news/healdsb...
         | 
         | "It was a desire to shade the recycled wastewater, not capture
         | the sun's energy, that first led city officials down the road
         | to the solar installation, Crowley said. The city hoped to
         | prevent algae from blooming in the two ponds -- which hold
         | treated water from the city's municipal sewer system."
         | 
         | They were going to pay to cover the reservoir, and instead they
         | get paid for the solar output.
        
         | hoosieree wrote:
         | https://www.smithsonianmag.com/innovation/california-is-abou...
         | 
         | Canals and reservoirs seem like perfect places to shade with
         | solar.
        
       | simonjgreen wrote:
       | It struck me last time I was in US (I'm from UK) how few
       | properties have solar panels on the roof. I wonder why that is?
       | Cheaper energy? Roughly 1 in 30 homes have solar installed in the
       | UK (https://www.theecoexperts.co.uk/solar-panels/popularity-
       | of-s...) though I can't lay my hands on stats for US.
        
         | HeyLaughingBoy wrote:
         | More and more outbuildings in rural areas have solar panels.
         | Installing solar is cheaper than getting permits/electrician to
         | run mains power to your buildings. I've seen new barns with the
         | roofs completely covered in solar panels.
        
         | saalweachter wrote:
         | In the US it's approximately the same -- 3.2%.
        
         | sethhochberg wrote:
         | There are a handful of potential reasons depending on where in
         | the US you're looking at, as usual there is wide variation by
         | state and by urban/rural divide:
         | 
         | - some states have little in the way of tax or other financial
         | incentive to help offset initial installation cost
         | 
         | - some neighborhoods have various visual restrictions, self-
         | imposed or otherwise, that may not accommodate solar panels
         | 
         | - some power companies have campaigned to limit net metering,
         | which limits the cost savings homeowners can see from solar to
         | protect the utility
         | 
         | - some local or state government officials view renewables as a
         | "political" issue in the sense of "yuppies getting bent out of
         | shape about global warming" and make efforts to limit renewable
         | usage for political points
         | 
         | - owners of most rental buildings don't pay for electric, the
         | tenants do, but the tenants cant make capital improvements and
         | the owner has little incentive to
        
         | 01100011 wrote:
         | Probably cheaper energy, and also perhaps a different
         | subsidy/regulatory environment. I know in California, the
         | utilities are fighting to make solar users pay more than they
         | currently do, saying the solar customers don't pay their fair
         | share of distribution and transmission costs.
         | 
         | Also, as a former leased-solar customer, there are some
         | downsides. Having solar in my area adds a few thousand dollars
         | to a roof replacement. Furthermore, solar panels are sort of an
         | acquired taste, aesthetically speaking.
         | 
         | When I had solar, it was nearly a wash in terms of how much I
         | saved vs how much I paid monthly to SunRun, the company I
         | leased them from. It did allow me to run my air conditioner
         | nearly all the time because I was incentivized to use the power
         | I generated, but it also meant I had a loud box outside my
         | bedroom window and the clicking of the relays woke me up many
         | mornings.
        
         | jseliger wrote:
         | The zoning and other regulations around solar are onerous in
         | the U.S.:
         | https://www.nytimes.com/2022/06/08/opinion/environment/defen...
        
         | pugworthy wrote:
         | It can really vary from community to community. My little town
         | (60k people, large university and Fortune 100 company campas)
         | seems to have a lot of house installations, but then income and
         | education levels are higher here, as well as a strong "green"
         | mentality.
        
       | henearkr wrote:
       | In the short term, THIS is the future I really believe in.
       | 
       | Then, a tiny bit further in time, using deserts.
       | 
       | And then even further, spatial solar.
       | 
       | Edit: this needs a bit of context, where I am living they are
       | erasing whole forests from mountain tops in order to install new
       | solar panel fields, so obviously I think that floatovoltaics are
       | very nice instead.
        
       | schimmy_changa wrote:
       | If anyone is interested, I just completed a Master's thesis on a
       | feasibility study for floating solar on a specific reservoir in
       | southern California: https://bren.ucsb.edu/projects/exploring-
       | feasibility-floatin...
       | 
       | Happy to answer any questions you might have about the
       | possibilities of the technology!
        
         | [deleted]
        
         | nomel wrote:
         | How do you service a panel, or whatever quantization, near the
         | center?
        
           | ncmncm wrote:
           | Leave gaps.
        
         | CSSer wrote:
         | This all seems pretty incredible and kind of like a no-brainer.
         | What are some of the challenges in a project like this? Are
         | there any limitations to scale?
         | 
         | Lastly, do you know off-hand if these bold claims (see below)
         | are exaggerated or oversimplified in any way?
         | 
         | > Covering just 10 percent of the world's hydropower reservoirs
         | with floatovoltaics could generate as much electricity as all
         | the world's operating fossil fuel power plants combined
         | 
         | > We found that countries in the Americas and Africa could
         | benefit most: even low coverage of reservoirs by floatovoltaics
         | should generate all the solar energy needed to decarbonize
         | their electricity sector. Brazil and Canada could be hotspots,
         | each requiring only about 5% coverage of their plentiful
         | reservoirs to satisfy their massive solar-energy needs. Last
         | year, Brazil implemented regulatory changes to help the
         | industry to develop (see 'Brazil's photovoltaic boom').
         | 
         | https://www.nature.com/articles/d41586-022-01525-1#ref-CR13
         | (linked in the article)
        
       | imgabe wrote:
       | Why are we not building giant solar arrays in the southwest and
       | high voltage DC lines to send the power to population centers?
        
         | codingdave wrote:
         | We already have built many solar arrays in the southwest. And
         | the power generated does get sent to population centers, both
         | from the renewable and the non-renewable plants. If you are
         | asking why we don't expand those efforts, that is a good
         | question... but it is absolutely already in place.
        
         | teekert wrote:
         | My guess: We run into problems here in the Netherlands now that
         | everybody with solar panels is producing huge amounts of power
         | around noon... And the grid can hardly take it anymore
         | (sometimes people can't push the power to the grid anymore
         | even). We can't store it, and most people don't have smart
         | devices that can start (like laundry) based on power
         | production.
         | 
         | That problem should first be solved.
         | 
         | Edit: In some provinces we can now neither build more power
         | plants nor add any larger industries because the grid can
         | simply not take it. I guess decentralization is key. For myself
         | I'm looking into a small EV that is usually at home and can be
         | charged during the day. But this only works when the car is at
         | home during day time. Another pro-wfh argument ;). Electric
         | scooters (max 45 kph), electric bikes (max 25 kph) and "speed
         | pedeleces" (max 45 kph, they are in between scooters and bikes
         | [0]) are also becoming really poplar here, they use
         | comparatively little, but it's nice when they replace cars.
         | 
         | [0]: https://www.speedpedelecs.com/ (it's a brand and a
         | category at the same time)
        
           | sandermvanvliet wrote:
           | Exactly this, (lack of) storage is the problem. Daytime
           | demand isn't high enough to deal with PV output leading to
           | cut offs on grid feed-in from consumer PV installations.
           | Given that car batteries aren't an option yet to power homes
           | this is a problem that will stick around for a bit.
        
             | cupofpython wrote:
             | >Given that car batteries aren't an option yet to power
             | homes this is a problem that will stick around for a bit
             | 
             | One was posted here not too long ago.. so this may not be
             | far off. But it's a bit of a chicken-egg situation because
             | powering your home with a car battery is not very practical
             | by itself. Investing in both solar and the car at the same
             | time would also be a hefty chunk of change for any
             | individual household
        
             | rootusrootus wrote:
             | Hardly anybody uses car batteries at this point, and not
             | just because of availability. It's a bit of a pain in the
             | ass compared to just buying LFPs. Even at fairly high
             | retail pricing for complete batteries, 30kWh of LFP is
             | $10K. That'll power a typical home for a day. If you just
             | buy cells and BMSs, it's cheaper. That's what most of the
             | off-grid folks do these days.
        
           | rcMgD2BwE72F wrote:
           | Maybe the Netherlands have excess solar power in some
           | days/hours, but what about neighboring countries?
        
             | cinntaile wrote:
             | Germany, Belgium and Denmark also have quite a bit of
             | renewable energy and the sun is usually similar, so they
             | usually don't really need it when the Netherlands has too
             | much either.
        
             | pixl97 wrote:
             | Building power transportation networks makes building out
             | large solar arrays look cheap. Getting the right of way and
             | environmental impact statements for these things that cross
             | rivers and cities is a massive undertaking.
        
             | Cthulhu_ wrote:
             | In the end, I'm confident little power is wasted; instead,
             | power is sold on the spot market at low and sometimes
             | negative rates. Datacenters will gobble it up to lower
             | their prices too, making "bottom feeders" like crypto
             | miners hit their "I am willing to pay this much" prices.
             | 
             | Then there's of course various energy storages; I believe
             | one thing they want to implement is that any leftover
             | electricity is put into generating hydrogen gas, which can
             | be stored and later burned cleanly to generate power if
             | needs be.
             | 
             | But yeah, that's a bunch of rambling from an amateur who
             | amortizes grid capacity; in NL we have a problem that the
             | grid is full. It's not really affecting day to day things
             | yet, but it means that new companies - power generating or
             | consuming - are not being connected to the grid because it
             | would cause overloads. I'm not sure if they bleed power off
             | anywhere yet.
        
               | henearkr wrote:
               | I'm sure that the solution is rather storage than
               | cryptomining (to me it looks like the same as just
               | burning the energy into waste heat).
               | 
               | For example, molten salt storage.
        
           | henearkr wrote:
           | I would say that home batteries like the Power Wall seem like
           | a nice solution.
           | 
           | However I am a bit worried about the lifespan of those
           | batteries and what happen to them at their end-of-life
           | (recycling? CO2e cost of making a new one?...)
        
             | blincoln wrote:
             | For standalone houses, seems like a bank of traditional
             | lead-acid batteries like datacenters use is a better
             | option. Doesn't require exotic materials, EOL handling is
             | well understood at this point, etc.
             | 
             | If I'm doing the math right, every ten car batteries in the
             | bank should get you about 8 kWh. The average home in the US
             | uses about 11,000 kWh/year[1], or about 30 kWh/day, so a
             | bank of 20-60 batteries seems like a good starting point,
             | depending on how much reserve capacity one is comfortable
             | with, how variable solar generation is, etc. That's an up-
             | front cost of about $4,000-$12,000 every 5-7 years, but at
             | least at the low end that should actually be cheaper than
             | paying for electricity from the grid over the same period.
             | A 20-battery bank should fit in about the same footprint as
             | a refrigerator.
             | 
             | That's also significantly cheaper than a PowerWall of the
             | same capacity[2], which was $7,500/14 kWh ($535/kWh versus
             | about $250-$275/kWh for lead-acid) before Tesla stopped
             | selling them without a solar panel bundle.
             | 
             | For apartments and other colocated housing, it might still
             | make sense as long as there was some sort of central vault
             | for the battery bank.
             | 
             | [1] https://www.eia.gov/energyexplained/use-of-
             | energy/electricit...
             | 
             | [2] https://solarmetric.com/learn/tesla-powerwall-review-
             | costs-s...
        
           | chrisseaton wrote:
           | Use the spare power to pump water up mountains.
        
           | 7952 wrote:
           | Giant solar farms (like Solar Star in LA) will connect to the
           | higher voltage grid rather than the low voltage grid used
           | domestically. Exporting large amounts of power and moving
           | that power geographically is exactly what this is designed
           | for. There may be issues with lack of capacity in district
           | and national grids. But it is a different problem to the
           | domestic solar issue. It can be solved by reinforcement of
           | existing lines, upgrading substations and building new ones.
        
           | chaosbutters wrote:
           | well, luckily for the US, we have massive hydro power dams in
           | the west that are low because of 20 years of drought, so we
           | can actually do pumped storage.
           | 
           | Ideally, we would pump salt water from oceans to the salt
           | water reservoirs and use surplus energy to desalinate to
           | refill the fresh water ones.
        
             | cupofpython wrote:
             | My thoughts exactly. Solar -> Desalination, with all other
             | energy consumption in the middle. Granted, I am not up to
             | date on desalination. I know MIT released something
             | recently but idk the details. Is energy the bottleneck now
             | or is it still material?
        
           | spockz wrote:
           | The main issue with our grid is mostly that we lack the
           | capacity to transport the power. In the past power generation
           | and heavy power consumption were typically relatively co-
           | located. Now, with wide spread energy production with solar
           | panels the energy is coming from everywhere and this power
           | needs to be transported to where it is consumed.
           | 
           | Moreover, in order not to overload the grid other power
           | generators need to scale down, even if those would be closer.
        
             | ryanmarsh wrote:
             | This is not true. Enron was famous (notorious) for
             | leveraging the, then, capacity of long distance
             | interconnects to move power from far off generation
             | capacity to advantageously priced markets. Just take a look
             | at the sheer size of CalISO, MISO, and ERCOT. You could
             | build solar anywhere and wheel it to where it's needed.
             | That's not the long pole in the tent (right now).
        
         | ranger207 wrote:
         | It's inefficient. HVDC is _more_ efficient over long distances,
         | but not enough to make it worthwhile
        
         | dokem wrote:
         | Because it's not economically viable, yet. It'll happen when it
         | happens.
        
         | ryanmarsh wrote:
         | "We" aren't building anything. Utilities are an income
         | producing asset for their investors. There are, in fact, a
         | multitude of utility solar installations going on right now all
         | over the US. These things take time to build and learn from.
         | It's not a slam dunk and the profits aren't guaranteed. Not
         | withstanding the unsolved engineering challenges, of which
         | there are many startups exploring.
         | 
         | We're not stupid it just takes time.
        
         | jakear wrote:
         | We are, see the multiple square mile installations in the
         | Mojave desert (in particular Rosamond). Output of that region
         | is ~520 MWh/acre.
         | https://www.google.com/maps/@34.8097025,-118.4587554,15367m/...
         | 
         | Side note, land in the area is available for purchase at
         | $3k/acre. And if you look closely, you can see the plots where
         | classic subdivisions were initially scratched into the surface
         | before land owners realized no one wanted their land even at
         | 3k/acre.
         | https://www.google.com/maps/@35.1339826,-118.0179071,2422m/d...
         | 
         | Edit: when I click the link, Google Maps helpfully informs me
         | that traffic in the region is "light". :)
        
       | Havoc wrote:
       | Quite confused as to why the army is doing this?
       | 
       | Schlepping fragile glass panels into battle doesn't sound viable
       | and if their aim is to green up their operations there are likely
       | better ways.
        
         | schimmy_changa wrote:
         | It's probably cost-effective, either compared to buying utility
         | energy or especially compared to backup diesel generators. It
         | could simply be a financial decision with some nice co-
         | benefits...
        
         | foxyv wrote:
         | It's for a military base on American soil. It's not a bring
         | with you to battle sort of thing.
        
         | zardo wrote:
         | I think they're willing to lose the panels in the event there's
         | a battle at Fort Bragg.
        
         | eschulz wrote:
         | The US military is sometimes quite involved in disaster relief
         | efforts, so I feel as though this makes sense. Also, I think
         | they're constantly tinkering around with new toys and
         | techniques.
        
       | winReInstall wrote:
       | $orry
        
         | maxerickson wrote:
         | Inventing Screamers is bad, actually.
         | 
         | https://en.wikipedia.org/wiki/Screamers_(1995_film)
        
       | 1970-01-01 wrote:
       | The Army's story has a much more interesting bit:
       | 
       | An electronic "recloser," funded by the Environmental Security
       | Technology Certification Program, is also being demonstrated as
       | part of the system. Reclosers respond to transient events, like a
       | tree limb brushing against a power line, to quickly reset the
       | system and restore power. This technology provides better
       | protection for system power lines and minimizes damage to
       | sensitive electronic equipment in the event of power
       | interruption.
       | 
       | https://www.army.mil/article/257375/army_floating_solar_arra...
       | 
       | https://en.wikipedia.org/wiki/Recloser
        
         | thedougd wrote:
         | Is this recloser different than the automated mechanical
         | reclosers I see around town? Solid state?
        
           | oneoff786 wrote:
           | I think they meant to write "electric recloser" and the
           | author didn't know what they were talking about. They're very
           | common and not noteworthy at all.
        
             | 1970-01-01 wrote:
             | I've never heard of a floating recloser, I think it's a
             | novel take on the device.
        
               | yellow_lead wrote:
               | What about a floating computer?
        
               | oneoff786 wrote:
               | Isn't that just a recloser on a barge
        
       | bryanwb wrote:
       | All these ridiculous Rube Goldberg contraptions for solar and
       | wind when we could just build more and different types of nuclear
       | reactors.
        
         | 7952 wrote:
         | Its not though. It is modest and conservative iteration of
         | existing technology that is very well understood and easy to
         | model.
        
           | cbmuser wrote:
           | Yet, solar does not produce electricity reliably, needs
           | additional electric backup power and uses large amounts of
           | material and area for producing relatively small amounts of
           | energy.
           | 
           | Nuclear works everywhere, everytime. There is a reason they
           | put nuclear reactors into submarines and aircraft carriers
           | and space probes.
        
             | 7952 wrote:
             | I am in favour of nuclear power but it is not so black and
             | white.
             | 
             | You have just listed three types of project with access to
             | vast resources. The number of nuclear powered vessels is
             | vanishingly small. And spacecraft overwhelmingly use solar
             | when they can. If your goal is to move a ship or launch a
             | communication satellite then the last thing you want to do
             | is add the considerable extra complexity of nuclear power.
             | Nuclear engineering is hard.
        
             | jhgb wrote:
             | > There is a reason they put nuclear reactors into
             | submarines and aircraft carriers and space probes.
             | 
             | The first two have ready access to infinite amounts of
             | coolant, which is absolutely not the situation
             | "everywhere", and the last one actually never delivered
             | more power than solar panels due to very inferior
             | power/weight ratio of all space-based nuclear reactors
             | produced to this date -- the most widespread space-based
             | reactor BES-5 generated something like 7-8 W/kg.
        
         | npc12345 wrote:
         | Solar panels do not suddenly render large swaths of fertile
         | land un-inhabitable.
        
           | cbmuser wrote:
           | Neither does nuclear. 80% of the population of the exclusion
           | zone in Fukushima prefecture have already returned to their
           | homes. People can even move back to Futaba, a town next to
           | the Fukushima Daiichi Nuclear Power Plant.
           | 
           | Nuclear power produces cheap, emission-free and reliable
           | electricity. It's as safe as wind power and it's life-cycle
           | emissions are even less.
           | 
           | > https://ourworldindata.org/what-is-the-safest-form-of-
           | energy
           | 
           | > https://www.iea.org/reports/projected-costs-of-generating-
           | el...
           | 
           | > https://www.energy.gov/ne/articles/what-generation-capacity
        
       | t_mann wrote:
       | Water surfaces are a great place for solar farms (the water
       | provides cooling which improves efficiency), but the real deal
       | are open sea platforms, not lake-based. The engineering
       | challenges seem big, though, I'm aware of only one company
       | deploying those successfully.
       | 
       | But it has promising potential: seas form the majority of the
       | globe's surface, and solar sea platforms seem to be, perhaps
       | surprisingly, biodiversity hotspots. Any solid structure in the
       | ocean will attract dwellers, but those platforms also seem very
       | popular with fish gathering underneath in large numbers.
        
         | algo_trader wrote:
         | > only one company deploying those successfully.
         | 
         | which one? i specifically recall a membrane based design, and
         | the other a floating grid
         | 
         | also, are there estimates of costs ?
         | 
         | Edit: lake floats are ~30% more expensive at the system level.
         | i am asking about ocean systems
        
           | t_mann wrote:
           | https://swimsol.com/
           | 
           | Disclaimer: I know someone who works there. These are meant
           | for ocean deployment, right now I believe they mostly use
           | them in locations with somewhat tempered wave conditions like
           | atolls and bays. It's a floating grid structure that holds
           | the panels a few feet above the water. I don't work there
           | myself, for cost estimates,... you'd have to contact them.
        
           | ncmncm wrote:
           | At last report there were 3 GW of floating solar. That number
           | is surely higher already.
        
         | Melatonic wrote:
         | Great idea but then again we come back to the problem of
         | getting that power back to land. I imagine ocean currents
         | complicate linking these things together or with big cables
         | back to land - not to mention big storms. I do really like the
         | idea of fish gathering below the platform - multiuse stuff is
         | always great. We could probably also do some hydropower while
         | were at it!
         | 
         | Best use case for something like this seems like for powering
         | remote outposts and islands - land is at a premium at these
         | places often plus you probably do not want to be clearing large
         | areas of uniquely biodiverse land for power delivery. Some
         | giant ones off the coast of Fiji could be a cool one for sure!
        
           | kurthr wrote:
           | Actually, you can manufacture ammonia from just water, air,
           | and electricity. And ammonia not only has great uses (right
           | now we burn a huge ammount of NatGas to make it) in
           | agriculture, but it's quite energy/space efficient for
           | shipping. We already ship quite a bit of liquified ammonia
           | (<200 psi at >100F). If you have a lot of "free" energy in
           | the ocean it makes sense to make/store/ship ammonia on the
           | spot.
        
             | ncmncm wrote:
             | This of course also enables storage for delivery of power
             | at night.
             | 
             | I think there is significant physical-chemical development
             | left to do for solid-state fuel cells that work with
             | ammonia and air, but it seems eminently doable.
        
             | rr888 wrote:
             | Thanks, with solar and wind there do seem many times when
             | there is a surplus of energy. I'm thinking somethings like
             | water cracking to H, Aluminium smelting or Steel Furnaces
             | could be done with such supluses but Ammonia sounds like a
             | good one for the list too.
        
           | ncmncm wrote:
           | A big enough farm can also be a focused microwave phased
           | array antenna, beaming power to any point overhead. Or even
           | multiple points, given more than one frequency.
        
           | jlengrand wrote:
           | I would imagine the problem for offshore solar farms wouldn't
           | be bigger as for offshore windmills? That is a relatively
           | expensive, but also not that difficult problem today? What
           | did I miss?
        
             | spinach wrote:
             | Waves.
        
               | notatoad wrote:
               | Are you saying that waves don't exist around offshore
               | wind farms?
        
               | ncmncm wrote:
               | They will tend to destroy offshore solar farms. Wind
               | farms are less affected because their cross-sectional
               | area near the water surface is small relative to their
               | mass.
        
           | miketery wrote:
           | > ocean currents complicate linking these things together or
           | with big cables back to land
           | 
           | They would be connected by cables to the ocean floor (depends
           | on depth I presume). But the currents shouldn't be an issue.
           | Storms unless there is debris should also be fine (but I
           | don't know what ocean weather is like).
           | 
           | Cables back to land are indeed an issue, especially with high
           | energy. Maybe we'll come up with efficient energy guns, or
           | create fuel on said platforms (hydrogen?).
        
             | hutzlibu wrote:
             | "Maybe we'll come up with efficient energy guns"
             | 
             | Very likely not. Creating fuel seems more practical, but
             | anchoring floating objects is a known problem as well.
        
             | FuriouslyAdrift wrote:
             | 30 ft (10 m) waves on a regular basis would not be unusual
        
               | bobthepanda wrote:
               | Presumably, that also affects cables for offshore wind
               | farms, and yet we routinely build those in seas that can
               | get rough.
        
         | [deleted]
        
         | colinmhayes wrote:
         | Offshore solar also neutralizes one of solars biggest downsides
         | which is that is uses far more space than traditional
         | generators. Land will only continue to get more expensive so I
         | suspect this will actually become a problem at some point,
         | especially in high density countries.
        
           | karterk wrote:
           | There are many large arid, desert-like land available in
           | almost every part of the world which can be put to use for
           | Solar. I don't think cost of land is a huge issue.
        
             | [deleted]
        
             | barney54 wrote:
             | The cost of land might to be a huge issue with deserts, but
             | the cost of transmission is.
        
               | ncmncm wrote:
               | Yet, the cost of transmission is not. A long transmission
               | line might be expensive to build in the first place, but
               | operating expense is near zero.
        
               | nine_k wrote:
               | Transmission from Arizona or Nevada to California looks
               | reasonable. The cost may be reasonable, too, at least the
               | Nevada part.
        
               | bombcar wrote:
               | The eastern half of Southern California _is already
               | desert_ so you might as well just use that, though one of
               | them had trouble getting of the ground and costs weren 't
               | the greatest: https://en.wikipedia.org/wiki/Crescent_Dune
               | s_Solar_Energy_Pr...
               | 
               | Others, including https://en.wikipedia.org/wiki/Ivanpah_S
               | olar_Power_Facility are doing better
        
             | ncmncm wrote:
             | Land use is absolutely no problem at all for solar.
             | 
             | Solar coexists synergetically with agriculture, operating
             | more efficiently, cutting water demand, and improving
             | yield. Also with parking (keeping cars cooler) and roofs
             | (extending life).
        
             | chipsa wrote:
             | If you put solar in the desert SW, and intend for it to
             | power homes in New England, how much does the transmission
             | lines to move that power cost? And how much do you lose in
             | transit?
        
               | tragictrash wrote:
               | There is an efficiency loss, but the problem is actually
               | the cost of building and maintaining the infrastructure.
               | 
               | Theres plenty of resources out there around this idea.
        
               | zdragnar wrote:
               | I don't recall where I had seen it, but there was a study
               | at some point on the cost of covering the Sahara in solar
               | panels. The CO2 emissions from the resources for the
               | transmission lines- in steel and concrete especially-
               | meant it would be a net positive CO2 contributor even
               | after shuttering fossil fuel power plants.
        
               | nine_k wrote:
               | This means that we need to learn how to build
               | transmission lines with less steel and concrete. Use more
               | aluminum maybe? More plastics and carbon fiber? More
               | glass?
        
               | bobthepanda wrote:
               | plastics and carbon fiber are made with hydrocarbons
               | generally. Aluminum might actually be worse, since
               | aluminum requires very high amounts of energy to produce.
        
               | nine_k wrote:
               | Hydrocarbons are not a problem per se. It's _burning_ the
               | hydrocarbons, specifically the carbon part, which has the
               | detrimental effect on climate.
               | 
               | Plastics and carbon fiber effectively keep the carbon
               | from becoming CO2.
               | 
               | Aluminum takes a lot of energy, but, unlike steel, the
               | process does not release any CO2, and is fully electric.
               | It can be powered by hydro (and often is), nuclear, or
               | solar energy directly.That's the point.
        
               | ncmncm wrote:
               | Solar energy used to produce aluminum has zero marginal
               | cost. So, unless you assume use of fossil fuels to
               | produce the power used to refine the aluminum, this is
               | nonsense.
        
               | Mwow wrote:
               | Another idea I saw on yt a few months back:
               | 
               | Charge some solid state battery (it's not battery it was
               | something better) and then transport it.
               | 
               | Similar on how we ship oil across the planet.
        
               | chipsa wrote:
               | A big problem with that is energy density. Hydrocarbons
               | are on the order of 50MJ/kg. Li-ion batteries are on the
               | order of .5MJ/kg.
        
               | ncmncm wrote:
               | Lithium tech at this exact instant is not the end state
               | of battery development.
        
               | foxyv wrote:
               | Robert A. Heinlein wrote a book called Friday that had
               | something like this. They would use huge solar arrays to
               | charge proprietary solid state batteries called
               | Shipstones which were used everywhere. There wasn't even
               | a power grid anymore because people would just buy a
               | Shipstone and put it into their house and replace it
               | every so often like coal in a coal bin.
        
               | johncearls wrote:
               | I love Friday and just reread it last weekend. Often I
               | think that Elon Musk believes he is a character in a
               | Heinlein novel. Tesla is Shipstone, the cars are just a
               | mechanism to build better batteries. SpaceX, that's just
               | DD Harriman from the man who sold the moon/sail beyond
               | the sunset. The Boring company is how you build Luna City
               | ala The moon is a harsh mistress. Or maybe a space
               | catapult. Or maybe, I'm just hoping for Heinleinian hero.
        
               | ncmncm wrote:
               | Anti-hero, looks like.
        
               | ch4s3 wrote:
               | I think the problem here is the weight of the batteries
               | and the need for power to move them. Maybe hydrogen by
               | electrolysis would be more favorable, but then you need
               | to pipe in water.
        
               | chipsa wrote:
               | You don't necessarily need to pipe the water to the
               | electricity, you can move the electricity to where the
               | water is (and if the electrolysis works with seawater,
               | you don't need freshwater either). And then you can turn
               | it into something like Methane or Ammonia for longer term
               | storage. And the long term storage is important to level
               | the power production over the course of months.
        
               | ch4s3 wrote:
               | I think the issue at hand is that long distance
               | transmission of electricity has transmission loss, and is
               | expensive from an infrastructure standpoint. The broader
               | point is that remote solar generation presents some
               | challenges.
        
               | ncmncm wrote:
               | Transmission loss matters very little anymore. You just
               | add more panels at the source. Marginal cost of the loss
               | is zero.
        
               | chipsa wrote:
               | Yes, I made exactly that point above. But the point I'm
               | making is that long distance transmission of water is
               | also expensive from an infrastructure standpoint,
               | possibly even more expensive than power (and also
               | sometimes has transmission losses, depending on how
               | they're moving it)
        
               | ch4s3 wrote:
               | > But the point I'm making is that long distance
               | transmission of water is also expensive
               | 
               | Oh yeah, in case I wasn't clear that's exactly what I
               | meant also.
               | 
               | The dream of covering a chunk of the Sahara in PV to
               | power Europe and Africa seems like tilting at windmills.
        
             | t_mann wrote:
             | Well, ideally you want to produce the electricity close to
             | where it's needed, and a significant proportion of the
             | world's population lives in coastal areas (much more than
             | near deserts I suppose).
        
               | tragictrash wrote:
               | This. You can't produce all of the worlds electricity in
               | deserts and ship it around the world
        
               | ch4s3 wrote:
               | As a thought experiment I once imagined electric trains
               | running between populated areas and desert solar farms.
               | Maybe they carry "green hydrogen" or perhaps just big
               | batteries. After a few minutes and a good chuckle I moved
               | on.
        
               | tragictrash wrote:
               | We have these 'electricity trains' already in a sense,
               | but they are tractor trailers containing fuel oil. It's
               | not as crazy as it sounds, but there are better solutions
               | available.
        
               | bobthepanda wrote:
               | Usually, the issue with this kind of thing is that
               | 
               | * this is a form of energy transmission that requires
               | labor for the actual transport (the train crew) and so is
               | automatically much more expensive and difficult than a
               | dumb pipeline or power line which requires much less
               | staffing
               | 
               | * it's hard to create energy storage that isn't also a
               | bomb in the wrong conditions, and train tracks pass
               | through populated areas. Fuel already has restrictions on
               | where it can be routed because there have been fuel train
               | explosions.
        
               | craftkiller wrote:
               | Why not? Australia is going to be exporting its solar
               | power to Indonesia through a 2,800 mile direct current
               | cable[1]. Thats approximately the width of the mainland
               | united states. It won't be as efficient as generating it
               | nearby but if its already commercially viable then it
               | will only become more viable as solar becomes cheaper and
               | more abundant.
               | 
               | [1] https://en.wikipedia.org/wiki/Australia-
               | Asia_Power_Link.
        
               | colinmhayes wrote:
               | COuntries will be looking to become energy independent,
               | especially with the russia fiasco Europe is facing. At
               | the very least they will try to make sure a majority of
               | their energy isn't imported from one country.
        
               | newsclues wrote:
               | You also can't produce all the clean energy via ocean
               | based solar and ship it to where humans live.
        
               | bobthepanda wrote:
               | Offshore cables exist, and if you want to go the route of
               | producing it into some intermediate form, a good majority
               | of heavily populated areas are also ports.
        
               | henryfjordan wrote:
               | There's a proposal to use solar power in the desert to
               | create pure Hydrogen gas via electrolysis, then fill
               | autonomous blimps with that hydrogen to ship it to where
               | energy is needed. You wouldn't want to fly over populated
               | areas, but otherwise seems like a feasible idea to
               | transport that solar power.
        
               | nine_k wrote:
               | For that you'd need to use kilotons of water a day, which
               | is usually hard in a desert.
               | 
               | It could work on an arid sea shore though, say, in North
               | or South Africa. But there seem to be closer-by large
               | consumers, and maybe producing freshwater would bring
               | more value than producing hydrogen.
        
               | goodpoint wrote:
               | > you'd need to use kilotons of water a day, which is
               | usually hard in a desert
               | 
               | North Africa, India, Australia and other have deserts
               | right next to the ocean.
        
               | ncmncm wrote:
               | There is absolutely no need for deserts to site solar
               | farms, so the premise is nonsense.
               | 
               | Solar farms are wholly compatible with agriculture. Look
               | up "agrivoltaics".
        
               | goodpoint wrote:
               | You very much CAN send electricity long distance and
               | there's been serious discussion of providing electricity
               | for Europe from north Africa.
               | 
               | Producing hydrogen near the ocean and shipping it on a
               | tanker is another realistic alternative.
        
               | ncmncm wrote:
               | There were huge projects started to site solar farms in
               | Africa, serving Europe.
               | 
               | They collapsed. The reason they collapsed was that there
               | turns out to be less than zero value in siting solar
               | farms in the desert, and solar panels have got so cheap
               | that you do better posting more of them nearby instead of
               | paying for the long cable.
               | 
               | The reason solar farms in the desert have negative value,
               | vs. siting nearby, is that panels in the desert get
               | hotter, so run less efficiently than over water or plant
               | life, and last many fewer years. Furthermore, panels in
               | farmland improve yield and water demand.
        
               | googlryas wrote:
               | Don't tell me what I can't do!
               | 
               | HVDC transmission losses are only around 3.5% per 1000km.
               | 
               | So you could get around 80% of the energy you produce in
               | Mali to Norway. Doesn't seem so bad.
        
               | ncmncm wrote:
               | Furthermore, there is strictly negative benefit to siting
               | solar farms in deserts. It makes them run hot, thus less
               | efficiently, and shortens their lifetime.
               | 
               | Siting solar on farmland increases farm yield and cuts
               | water loss.
        
             | dragontamer wrote:
             | Desert-like land is terrible for solar panels because the
             | solar panels get too hot (and lose efficiency).
             | 
             | The big, successful desert solar power projects I've seen
             | are giant arrays of mirrors using some kind of weird heat
             | engine, rather than PV-cells.
             | 
             | Cheap, widespread desert solar power would be good to
             | figure out, but with regards to PV-cells, desert
             | environments look like a no-go.
        
               | dmurray wrote:
               | How much efficiency do they lose? Desert land is orders
               | of magnitude cheaper than German farmland, and the latter
               | appears to be economic to cover in PV panels, so if we
               | could get the cost of materials down we could deal with
               | losing 20% or maybe even 90% efficiency.
        
               | dragontamer wrote:
               | I don't know the answer to your question, but lets assume
               | 20%.
               | 
               | If PVs are 20% less efficient in the desert, you'll need
               | 25% more PVs. (Ex: Instead of buying 1MW worth of panels,
               | you need 1.25MW of panels to generate only 1MW of power)
               | 
               | If PVs are lol 90% less efficient in the desert, you'll
               | need 900% more PVs (instead of buying 1MW worth of
               | panels, you need 10MW worth of panels to make 1MW)
               | 
               | -----------
               | 
               | Because PVs are the "expensive part" of solar power (and
               | land is really, really cheap, even German Farmland),
               | we're more interested in reducing the number of PV-panels
               | to buy, rather than reducing the cost of land
               | acquisition.
        
               | ncmncm wrote:
               | Panels that normally get 20% conversion efficiency are
               | typically 12% in the desert summer. So, a huge loss.
        
       | firstSpeaker wrote:
       | How would this impacts the marine life? Lakes, and most water
       | bodies for that matter, are complex ecosystems.
        
         | mrfusion wrote:
         | If you space them out enough you wouldn't have huge areas of no
         | sun. It would emulate an ecosystem of water under shade trees.
         | Shade actually attracts a lot of biodiversity.
        
         | rr888 wrote:
         | This seems to be most important part. It could be beneficial as
         | prevents evaporation and warming. LA reservoir even has
         | floating balls for this
         | https://www.nationalgeographic.com/science/article/150812-sh...
        
         | g8oz wrote:
         | All local impacts have to be weighed against the global impact
         | of CO2 emissions.
        
           | lm28469 wrote:
           | There are no ways to accurately predicts how eco systems
           | react and how far the domino effect would go. You could wipe
           | out entire food chains and not be aware of it before it's too
           | late
        
             | tester756 wrote:
             | there are no experts in that domain?
        
           | Cthulhu_ wrote:
           | I don't think CO2 emissions are much of a priority in
           | warfare.
        
         | wolfram74 wrote:
         | The article describes artificial reservoirs as the water body
         | of choice, which are less complex (partly because they already
         | destroyed the ecosystem that was there) than naturally forming
         | lakes, and has the added benefit of reducing solar driven
         | evaporation in the same vein as this[0]
         | 
         | [0]https://www.youtube.com/watch?v=uxPdPpi5W4o
        
         | schimmy_changa wrote:
         | It's an area of open research, but especially if it doesn't
         | cover 100% of the water body it's fairly benign:
         | https://www.sciencedirect.com/science/article/pii/S136403212...
         | 
         | For instance, birds perch on the panels, turtles loaf on the
         | floats, fish hide from predators under them. It changes the
         | water body, but not in a way that would be different from, say,
         | trees that have fallen halfway into the water and are shading
         | part of the surface.
        
         | flembat wrote:
         | Including canals, which the author disclaimed for some reason.
         | Here at least they have all kinds of aquatic and bird life.
        
           | ncmncm wrote:
           | ... which would then also benefit from the presence of
           | floating solar panels. Panels floating in a canal would need
           | to be anchored against current, easily done.
        
       | alonmower wrote:
       | Wonder how effectively this could be paired with pumped water
       | storage. Excess solar energy could get used to pump water that
       | could get used to provide power at night/store energy for cloudy
       | days. You'd also get a double bang for the buck for the space
       | being used if the water is covered with panels, and solar panel
       | coverage of the reservoires would presumably help minimize
       | evaporative losses
        
         | schimmy_changa wrote:
         | It's likely well-suited for that, but in general hydro +
         | floating solar could be ideal as the power infrastructure is
         | already in place. Pumped hydro is not 100% ideal as the drastic
         | changes in water level can cause some problems with designing a
         | solid system.
        
       | vastbinderj wrote:
       | I run a 46 panel array on my rooftop at my home in Florida. On a
       | good day it generates around 80 kWh. On a cloudy day, 35-45 kWh.
       | On stormy days it generates about 15 kWh. It cost me $40,000. At
       | night, it generates no power, but needs a 20amp AC connection for
       | the controller and 60 amps for the micro inverters.
       | 
       | I save about $50-80 a month on my electric bill. Solar in its
       | current incarnation is not ready to power the world, it destroys
       | the biome in which the panels are deployed, costs an awful lot to
       | fabricate....
       | 
       | I am more interested in personal nuclear energy or recycled
       | nuclear energy production. Solar is a distraction that when you
       | start asking the right questions, feels more like gas-lighting
       | than a solution to renewable sources of energy.
        
         | bojan wrote:
         | That sounds horribly expensive. I have a 12 panel array here in
         | the Netherlands, and I paid EUR 3500 for it.
         | 
         | There was no biome on my roof that I was aware of.
        
         | ncmncm wrote:
         | You can buy a pallet-load of 45 350W-peak panels for under
         | $7000 nowadays. A used Nissan Leaf at 60% battery capacity is
         | another $7000, and a converter/inverter to charge/discharge it
         | is under $1000.
        
         | nomel wrote:
         | Lets say 50kWh/day average, giving 1,500kWh/month. If it's only
         | saving $65 on your electricity, doesn't that mean your
         | electricity is around 4c/kWh? My math must be wrong. Are there
         | other fees, or did you also include the payment for the panels?
        
       | fffobar wrote:
       | I wonder if this could have a military purpose as well, as in
       | whether this could be used in a combat area. Any of the other
       | types of electrical power generation systems are very
       | "centralized", as in there is only a few points where just a few
       | hundred kg of hexagon delivered by a precision missile that slips
       | past air defense would easily terminate the power production.
       | 
       | On the other hand, a mesh of solar panels deployed over a larger
       | body of water is a pretty difficult target to destroy. Imagine
       | that it is floating over a 1km by 1km (or even 1 mile by 1 mile)
       | area - what are you going to use against it? Unguided artillery?
       | Would take a huge amount of shells, even though they're cheap
       | it's probably infeasible. The same with unguided air-dropped
       | bombs. Guided munition? Even worse than the unguided stuff, no
       | high value targets to hit. The only way to defeat such a meshed
       | power plant would be a small nuclear bomb.
       | 
       | (the above assumes that there's no single energy collection
       | point, of course, otherwise that place would be targetted)
       | 
       | The other upside is that there is no need to supply oil, which is
       | currently the preferred way of delivering energy to the combat
       | area. The downside is the time it would take to deploy such a
       | mesh, a diesel generator works pretty much instantly.
        
         | politician wrote:
         | The power cabling connecting the array to the shore seems like
         | a nice spot to target.
        
         | _wolfie_ wrote:
         | I have no idea how fragile solar panels are, but wouldn't
         | cluster bombs or possibly thermobaric weaponry work reasonably
         | well against large surface areas like this?
        
           | Retric wrote:
           | US Army strategy often assumes air superiority by US forces.
           | 
           | Mortars are simply a more likely risk than cluster bombs.
           | Further it's fuel rather than generators that's a problem,
           | it's bulky, flammable, and finite.
        
           | lm28469 wrote:
           | Sparkling sand (or anything else) over them would be enough
           | to absolutely destroy their output
        
             | ncmncm wrote:
             | That would have hardly any effect. Soot would, though.
        
         | leeoniya wrote:
         | > Imagine that it is floating over a 1km by 1km (or even 1 mile
         | by 1 mile) area - what are you going to use against it?
         | 
         | an EMP?
        
         | oneoff786 wrote:
         | Seabird feed laced with laxatives
        
         | glitchc wrote:
         | The weakness isn't the array itself but the cable(s)
         | transporting the energy to where it needs to be consumed.
         | 
         | Cut the cable and the array is just more debris floating in the
         | ocean.
        
         | omega3 wrote:
         | People are mentioning thermobaric weapons, small nuclear bombs
         | where in fact a couple of bog standard 155m shells with
         | proximity fuses would render something like this inoperational.
         | Alternatively send out a single CAS like A10.
        
         | hhr wrote:
         | Out of top of my head this
         | (https://en.wikipedia.org/wiki/TOS-1) can destroy such target.
        
         | Consultant32452 wrote:
         | Almost certainly usable by the military, but not the way most
         | people in the thread are responding. The military does a lot of
         | humanitarian aid and rebuilding type work outside of war zones.
         | If this solar array can be quickly and easily deployed off a
         | boat and then you just drag a cable on shore to power a local
         | town that could be very useful compared to having generators
         | and having to ship diesel constantly.
         | 
         | Massive Earthquake knocks out the infrastructure in Haiti? Just
         | send the solar boat and, even without batteries, you have a
         | daytime power plant set up in a day. I wonder how much power
         | storage you could get with a hand full of tractor
         | trailer/shipping container sized batteries.
        
         | Cthulhu_ wrote:
         | I'm not convinced that a solar array / electricity production
         | would be the prioritised target if they were in range.
        
         | pengstrom wrote:
         | Is it not more efficient for the larger ships to over provision
         | on nuclear?
        
           | jalk wrote:
           | Deploying the panels at sea, dragging them behind a warship,
           | seems to be quite a challenge compared to deploying in a
           | "pond" of calm water
        
         | closewith wrote:
         | With respect, an M777 battery could saturate a grid square in
         | minutes. The expected injury radius of a 155mm is ~150m, so
         | conservatively 100 rounds would blanket a 1km*1km array. A six
         | gun battery can fire ~36 rounds per minute comfortably. 100
         | rounds could be fire and the battery could be packing up before
         | the first one hit.
        
           | 2OEH8eoCRo0 wrote:
           | What's the range? 15 miles?
           | 
           | I agree though. Solar on the battlefield doesn't make sense
           | since it is not mobile and cannot be concealed or protected.
           | 
           | I do think the centralized nature of massive diesel
           | generators and their fuel supply lines are a tactical weak
           | point though. I like the idea of flexible distributed power
           | grids for troops but I'm not sure solar fits the bill.
           | 
           | It would be cool to hear some input from generals and see
           | some proof of concepts.
        
             | closewith wrote:
             | > What's the range? 15 miles?
             | 
             | For M30A2, 70km or ~43 miles.
        
           | htfuuufhhuff wrote:
           | That injury radius must be on land right? Like if it hits
           | water how destructive could the splash be?
        
             | closewith wrote:
             | Gunners would use proximity fuzes to airburst above the
             | target in this application. TBH 100 rounds is wildly
             | conservative - I can't imagine a better target for
             | artillery than a fragile and static solar array.
        
           | Tuna-Fish wrote:
           | Yeah, people drastically underestimate the raw firepower of
           | artillery. The M270 is called "the grid square removal
           | system" for a reason. (Grid square refers to 1km x 1km area.)
        
             | [deleted]
        
             | ryanmarsh wrote:
             | This. As a former infantryman the one thing that still
             | strikes me with awe to this day is the destructive power of
             | artillery. People cannot fathom what it's capable of.
             | 
             | Go up in a tall building, maybe to the 20th floor or so.
             | Eyeball a built up area 1km square. Now picture every
             | structure reduced to rubble in an instant. Now imagine 10km
             | square reduced to rubble in just a few minutes.
             | 
             | Quick work for an artillery battery.
        
               | jcims wrote:
               | Never experienced it myself but seeing those piles of
               | shells from WWI just sends my brain to uninitialized
               | memory.
               | 
               | https://rarehistoricalphotos.com/shells-creeping-
               | bombardment...
        
               | [deleted]
        
               | [deleted]
        
             | somerandomqaguy wrote:
             | https://www.youtube.com/watch?v=IUvcdKGD-FM <-- What it's
             | like be hit by 130mm artillery.
             | 
             | One thing that the video can't simulate is how loud those
             | explosions are. You don't just hear the sound wave, even
             | from a safe distance you feel the pressure wave in your
             | entire body.
        
             | HeyLaughingBoy wrote:
             | Reminds me of a day I was fishing from a pier at the beach
             | some time ago. Older dude came up to me and started talking
             | and got into his "time in 'Nam." He pointed at some
             | apartment buildings across the bay, "we'd call in an
             | airstrike and they'd make one pass and everything would be
             | gone. Those buildings? You'd just see some bricks and
             | rubble left behind." To 25 year-old me that was a pretty
             | sobering thought.
        
             | chipsa wrote:
             | We no longer have the M26 rockets used in grid square
             | removal. They've all been decommissioned in favor of
             | M30/M31 GMLRS guided rockets, which don't have
             | submunitions. Oddly, "grid square removal system" is
             | actually a backronym, as the original designation of the
             | M270 was General Support Rocket System (GSRS)
        
               | closewith wrote:
               | That's largely due to the general move away from cluster
               | munitions. There's still plenty of the M30 series, whose
               | 160,000 preformed tungsten fragments would be an ideal
               | weapon for use against a fragile and static solar array.
        
               | chipsa wrote:
               | As a note: the US Military isn't going away from cluster
               | munitions because we don't want to leave UXO for
               | civilians to accidentally blow themselves up with, but
               | rather because we don't want to leave UXO for US military
               | to accidentally blow themselves up with. If we drop 12x
               | M26 missiles on a grid square, then that's something like
               | 7.7k submunitions. With a 14% dud rate, that's 1k
               | submunitions somewhere waiting for us to roll over them.
        
         | krisoft wrote:
         | > Imagine that it is floating over a 1km by 1km (or even 1 mile
         | by 1 mile) area - what are you going to use against it?
         | 
         | Shrapnel generating warhead 100 meter over the solar field.
         | Good luck finding and bypassing all the damage and short
         | circuits.
         | 
         | Or send the precision missile to where the cable lands.
         | 
         | > the above assumes that there's no single energy collection
         | point, of course
         | 
         | Probably not a literal single point, but I would assume any
         | solar field would have a relatively low number of shore
         | connections.
        
         | lm28469 wrote:
         | > Imagine that it is floating over a 1km by 1km (or even 1 mile
         | by 1 mile) area - what are you going to use against it?
         | 
         | Same way you render a nuclear power-plant useless, cut the
         | cable(s)
        
         | t_mann wrote:
         | > The only way to defeat such a meshed power plant would be a
         | small nuclear bomb.
         | 
         | Or to quietly cut off the underwater power cable.
        
         | usrusr wrote:
         | > The only way to defeat such a meshed power plant would be a
         | small nuclear bomb.
         | 
         | Unless actively defended: set collision course. If you suspect
         | that it might be a tie, set collision course on an unmanned
         | confiscated civilian vessel.
        
           | ncmncm wrote:
           | EMPs are cheap to produce.
        
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