You do realize solar isn't viable in norther parts, due to peak demand being during cold winters and just less sun in general? Solar is great in the south where peak demand is during the warm sunny summers.
Even in the southwest this is a problem - peak output from residential rooftop solar is mid-day but peak demand is early evening when people are getting home, cooking dinner, charging their EVs, etc. Without some major changes to residential storage or large grid-attached storage systems, solar alone isn't going to cut it.
Don't get confused by peak net-demand i.e. demand that is left after you subtract solar.
The newly cheap midday power should be driving demand towards that time period but it won't show up on net demand charts, which will show the famous duck curve belly at that time. That doesn't mean people aren't using energy at that time.
In fact the main way to detect this demand shift in a net demand graph is to see that the evening peaks are dropping year over year, even as they seem relatively larger compared with net demand when solar is working.
But anyway, in California the massive deployment of batteries in the last few years has already solved this problem. Compared with peaking gas plants that only run once a day for a few hours batteries are both cheap and clean.
I'd agree. Clearly solar is sun-dependent, and other options may be more suited to other locations.
That said, electricity is one form of energy that is really cheap to distribute (once you are close to "the grid".) Which means that moving electricity from sunny places to darker corners is very practical.
There are some economics in play. Remote populations (like on islands, or in Alaska) are unlikely to be connected anytime soon. These populations are generally dependent on coal.
Nuclear might be appealing, but refueling nuclear takes time. So if it's your only electrical source, you need two reactors, each capable of supplying enough power. And of course the expertise to run it (expertise possibly harder to find in far-north Alaska.)
Ultimately diesel is likely to remain the fuel of choice for small communities because engines are cheap, fuel is easily transported, and expertise is local.
incidentally i don't think it's true that engines are cheap; diesel-engine generators seem to be on the order of 100¢ per watt, while pv modules are 8¢ per watt and falling. at least, at the few-kilowatts level where i've been able to find prices. maybe wärtsilä's multi-megawatt diesel power plants are cheaper per watt but they don't seem to publish a price list
maybe you just mean that diesels and especially otto engines scale down to smaller scales than nuclear or coal power plants?
It kinda is though because refueling is a long job. Typically in the order of weeks. I'm not sure most communities would enjoy running on no power, or limited power for some number of weeks every couple years.
And sure, maybe "fast refueling " gets built into new designs. A day or two is likely the longest you can tolerate though.
Obviously that's before we consider other concerns of being dependent on a single source. I'm not sure living in remote Alaska, being dependent on a single complex machine for power is an ideal situation.
i edited that into my comment while you were writing yours, yeah. norway and finland have capacity factors of 6% for solar (compared to 30% here and 21% in the usa) and north of the arctic circle you'd need enough batteries to power you all winter long (though if i did my calculations correctly, it turns out that total yearly insolation rises after you cross the arctic circle)
this is why scandinavian countries are using a lot more hydro and wind than solar. wind and especially hydro are cheaper even than solar, but wind and especially hydro are much more limited resources
still, consider a counterfactual where somehow norway had to satisfy all its energy demand from solar. they burn 78.8 million barrels of oil per year, which is 15.3 gigawatts. they consume 124.29 billion kilowatt hours of electricity per year, which is 14.18 gigawatts (already over 95% hydro and wind, with no significant nuclear or solar component). they burn 3.98 billion cubic meters of natural gas per year, which at .0364 megajoules per liter is 4.59 gigawatts. all of these together (assuming no overlap) are 34.1 gigawatts, and over 5.55 million norwegians, that's 6.1 kilowatts per norwegian. (if that sounds like a lot more than your house uses, that's probably more because most of it is used by transport and heavy industry than because norwegians have to heat their houses more.)
34 gigawatts divided by a 6% capacity factor is 570 gigawatts of solar cell nameplate capacity you'd need. at 02021 german costs of €0.60 per (nameplate, peak) watt of utility-scale solar, (including modules, inverters, permitting, inspection, customer acquisition, etc.; see slide 48 of the fraunhofer deck linked above) this would cost €340 billion, about 8 months of norway's gdp. if you could only spend 5% of their gdp on the transition, you could get it done in about 15 years, maybe 25 if you need batteries
of course it's unnecessary because norway is already renewables-powered! but my point is that solar cells are now so cheap that they're a viable power source even in ridiculously polar countries. incidentally, they now cost half what they did in 02021, so the price would be a lot less now
antarctica is much more interesting than the arctic, though, since there's land there
> You do realize solar isn't viable in norther parts
I lived in the Yukon for 4 years, would drive many hours due south to get to the capital of Alaska.
I met dozens of people that had off-grid houses powered entirely by solar. Remember the sun is up for 20+ hours a day in summer. In winter they had to be careful, but the had full houses with washing machines, fridges, etc. etc.
This was in 2015 when people had lead acid batteries and only a few kW of panels. I bet it's much more common now.
How would transmission solve the massive electricity demand during cold winter nights? Even in more southern areas generation during winter is lower, then pay the massive loss of transmitting that so far north and it is no longer viable.
hvdc transmission doesn't have massive losses from transmitting long distances, so you could literally transmit power from the tropics or even the other hemisphere. but overprovisioning solar locally is probably cheaper
Are there hvdc transmission lines already spanning those kinds of distances? How much raw material and upkeep does that require? If over-provisioning solar, how much more surface area would be needed to have the solar? Seems like the additional costs would pile up to get to current energy needs being met by just solar.
you'll probably be interested in reading https://en.wikipedia.org/wiki/High-voltage_direct_current. it says typical losses are 3.5% per 1000km, and typical voltages are 100–800 kilovolts, but china built a 12-gigawatt 1100-kilovolt link over 3300km in 02019
unfortunately i don't have a good handle on how efficient that link is. the numbers above suggest it would be about 89% efficient, but those are for lower-voltage systems
in general you expect the resistive losses in the cables, at a given diameter and power, to scale with the inverse square of the voltage, so an 1100-kilovolt link should have 47% less resistive losses than an 800-kilovolt link at the same power level running over the same cables. however, corona-discharge losses increase at higher voltages rather than decreasing, and i don't know which one is dominant. so i don't know if that link is closer to 89% efficient or closer to 95% efficient
the distance from the north or south pole to the equator is of course 10000 km, but people don't build very near the poles. for example, from svalbard to algiers is 4700 km. so, yeah, there are hvdc transmission lines already spanning those kinds of distances, but not quite that far yet
transmission lines require utterly insignificant quantities of raw material, but where they cut through forested terrain, they do require upkeep. in the meeting of a tree and a megavolt, neither one comes out unscathed
for some calculations on how much you need to over-provision solar, see my earlier comment at https://news.ycombinator.com/item?id=40724349 considering a counterfactual where somehow norway had to use solar. 6.1 average kilowatts per norwegian at a capacity factor of 6% works out to 102 kilowatts peak per norwegian. if you're using low-cost 16%-efficient solar panels (as i assumed you would in my cost estimate, even though mostly people spring for the more efficient 'mainstream' ones) that would require 635 kilowatts of sunlight per norwegian, which is 635 square meters per norwegian (we rate solar panels on the assumption that sunlight is 1000 watts per square meter). 635 square meters is 25 meters square, .000635 square kilometers per norwegian. multiplying that by 5.5 million norwegians gives you the truly immense area of 3500 square kilometers of solar panels
but wait! that's not all! you can't just lay the panels out flat on the ground and expect them to get a 6% capacity factor. you have to angle them toward the equator and spread them out so they don't shade each other. oslo is at 60° north, so your panels need to be angled at 60° from the horizontal, toward the south. maybe a bit more if you want to increase power production in winter, say 69°. so you have to space them out by 1/cos 69° ≈ 2.8. so actually you need 9800 square kilometers for your €340 billion of solar panels. how much space will you have left?
a lot, it turns out. norway is 385000 square kilometers, so this is still just 2.5% of the country
so norway, despite being the #2 highest user of energy per capita in the world after canada, and having cities that are literally inside the arctic circle, could switch to all solar. it's totally feasible. fortunately they have plenty of hydropower and wind so they don't need to
In that transmission is very expensive and inefficient in ways that are challenging to improve because of physics? Transmission isn't getting a lot better very quickly, and certainly not by waving a magic wand.
transmission is in fact getting a lot better very quickly, becoming much less inefficient, because people rose to the challenge; i took some notes about recent hvdc systems in https://news.ycombinator.com/item?id=40725189
It's definitely a generation issue. When there's no sun(overcast, nighttime) there's no energy. This doesn't even factor in solars quick deterioration from peak performance and the cost of the panels and environment damage from producing them.
Yeah, I think people looking at just the upfront cost are not really acknowledging or addressing that solar panel installations degrade faster than a nuclear reactor. They also take up more space and as you mentioned will likely end up causing more damage to produce at planetary scale. They are definitely great when coupled with batteries for many use cases including decentralizing aspects of the grid for residential and smaller scale usages, but the raw performance of nuclear is impressive and exciting. So little inputs needed for how much you get, and for how long too. There are old reactors still producing after over 50 years…that is mind-boggling.
Who knows how far the tech can be pushed with modern advancements and less blockers on developing the technology further. It should be in the toolbox as part of a strategy for renewable energy needs on Earth and beyond.
nuclear energy is very exciting and absolutely crucial for space exploration, but not economically competitive with solar in the foreseeable future on earth's surface
there are also solar panels still producing power after 50 years; they do degrade a little, especially in the first ten years, but the 20–30 year panel lifetimes you see published are more of a warranty and accounting issue than anything else. (of course some panels crack or yellow within a year or two)
it's true that solar farms take up a lot of space, but even in high-density countries like japan there is room for them. singapore might have a problem tho
What would surface area needs be like for over-provisioning needs in the US? What if we want to scale energy production by 2x or 10x or 100x for advanced industrial and commercial usage needs in the future? I think then the solar panel approach becomes limited on earth.
You’re right that the panels don’t degrade a ton. I read online that after 20-30 years they might drop 15% efficiency. For residential usage that might be okay, but it does mean needing upkeep and worrying about baseline potential dropping, which in some climates could be bad.
I do think a combination of the technologies is best, since scaling up energy production will be simpler and easier and more resource-friendly with nuclear than with more solar. Moving up the Kardashev scale will require capturing all the energy that can be captured from all sources so why let any go to waste. :)
If you want to scale to 100x power you're going to have to rely on solar power even more than we already do. You seem to be awfully attached to the idea that the reactor must be located on earth. Solar power is fusion power with the reactor being located in space. It is very unlikely that humanity can build a bigger reactor.
humanity, defined loosely, can definitely build a bigger reactor than the sun. the milky way is a trillion times bigger than the sun, and mostly made up of stars (as opposed to large black holes, which are probably effectively inaccessible), so there's plenty of material available
already-existing natural blue hypergiants can reach energy outputs several million times that of the sun, in large part because they're on the order of 100 times bigger, usually limited only by the eddington mass limit. bat99-98 is estimated at 226 solar masses. so designed artificial stars can clearly reach that size, and conceivably, with a better understanding of plasma dynamics, they could be stabilized. in fact, we already know† how to build an even larger star: if you build a star of very low metallicity (similar to natural population-iii stars, of which possibly none survive today), its eddington mass limit is much higher, around 1000 solar masses
more likely, though, the humans will instead build a larger number of smaller, safer reactors. microscopic black holes can convert mass into hawking radiation at manageable photon energies and useful power levels. the necessary experimentation poses no risk of creating a large black hole (the density of matter necessary to grow small black holes to macroscopic proportion doesn't exist outside of the cores of stars, and the necessary quantity of matter at those densities is also literally astronomical) but will surely involve many explosions as starving black holes explode in a final tantrum of high-energy gamma rays, and of course must be carried out in free fall to prevent your nascent black hole from simply falling between the atoms of your laboratory floor before exploding deep inside your chosen planet
constructing larger reactors, by contrast, does pose a risk of producing phenomena such as disappointing white dwarfs, neutron stars, and black holes, or worse, supernovae, rather than a useful power source
if we believe dyson's calculations, though, a much more worthwhile thing to do is to figure out how to slow down our entropy production enough to preserve life into the cold, dark post-stellar era
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† i mean we know in scientific terms what the structure of such an artificial star would be, where to find the materials, and what would be required to bring them together in the right way. it's fairly simple, actually. the only difficult part is getting a large enough budget to build the necessary fleet of spacecraft to harvest 10³³ kg of hydrogen and helium, about a billionth of the milky way, and bring it together over a distance of several light years; plausibly you need on the order of 10³⁵ spacecraft, about 120 doublings of a von neumann probe
yes, as you approach kardashev type 1 you will definitely want to start harvesting sunlight from von neumann probes on solar orbit
including transportation, natural gas, etc., but not including foods like corn and canola, the usa uses 100 quads per year, or 3.3 terawatts in si units. its average utility-scale solar power capacity factor is 21%, so you'd need 15.7 terawatts peak of solar farms to supply that, before scaling up by 2× or 10× or 100×. 15.7 terawatts of 24% efficient solar panels would require 65 terawatts of sunlight, which is to say, 65 billion square meters or 65536 square kilometers (to pick a round number). this is of course 256², so, like the entire spectrum of mainstream political opinion in the usa, it would all fit between houston and austin. you could drive around it in a day
well, not quite; that's 29° latitude, so you need to space your panels apart by a factor of 1/cos 29°, about 14%, so they don't shade each other. also in texas, unlike any other phenomenon known to humanity, it would be a bit smaller, because texas has a 25% capacity factor; the reason the usa has an overall lower solar capacity factor of 21% is that some solar farms are in suboptimal places like maine (10%) so the power doesn't require long-distance transmission
so right now it's really tough for nuclear to compete with solar on earth
