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Comment by margalabargala | Hacker News Reader

> One kilogram of uranium-235 (50 cm^3) can theoretically produce about 20 terajoules of energy. One square kilometer of solar panels can theoretically produce the same amount (as 50cm^3 U235) in a day.

Does the US have more 50cm^3 sized blocks of U235, or more square kilometers of land with low land values and high annual insolation?

There's an estimated 6 million tonnes of mineable uranium reserves in the world [0]. Of which 0.72% is U-235, so we have a worldwide reserve of 43200 tonnes, or 43.2 million Kg U-235.

Arizona is about 300k square kilometers. If we covered an area 10% the size of Arizona in solar panels, then they would have produced more energy than all the world's known U-235 in just four years. And would continue producing after those four years are up.

[0] https://world-nuclear.org/information-library/nuclear-fuel-c...

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There is way way more uranium than that. It is surprisingly common. And harvesting it from seawater opens up a supply that dwarfs any mining concept.

https://en.wikipedia.org/wiki/Uranium_in_the_environment

>> Uranium is a naturally occurring element found in low levels within all rock, soil, and water. This is the highest-numbered element to be found naturally in significant quantities on earth. According to the United Nations Scientific Committee on the Effects of Atomic Radiation the normal concentration of uranium in soil is 300 μg/kg to 11.7 mg/kg. ... It is considered to be more plentiful than antimony, beryllium, cadmium, gold, mercury, silver, or tungsten and is about as abundant as tin, arsenic or molybdenum.

How uranium ore becomes fuel rods: (Actually a rather simple process imho.)

https://youtu.be/9x7DozCqLxU

https://youtu.be/c7ehyxRBMbw

Nuclear is renewable for the same reason geothermal is renewable, and you can get uranium out of seawater for the same price as mining it

https://www.tiktok.com/@nuclearsciencelover/video/7092135813...

TikTok is not credible. You can’t click the links or easily verify the conclusions. It’s the ultimate in trust me bro science.

Why do people bother mining it?

Because mining it is relatively cheap. So cheap, in fact, that it is economical to throw away >95% of the fuel rather than try to burn it all or recycle it.

Fuel costs are 10% of the cost of nuclear electricity. The vast majority is financing.

> you can get uranium out of seawater for the same price as mining it

> Why do people bother mining it?

> Because mining it is relatively cheap.

Something does not add up here.

Mining exists and is cheap enough that there is no incentive to invest in something new, even if it might just as good. Particularly because "just as good" is rarely a good reason for changing and investing, it would have to be significantly better.

(Though I have no real opinion on whether seawater extraction really is just as good...somewhat dubios)

FWiW the latest in a long line of seawater extraction papers is (2020):

https://pubs.rsc.org/en/content/articlelanding/2020/ta/d0ta0...

https://sci-hub.ru/10.1039/D0TA07180C

which has the weasel phrases

     uranium production costs could be reduced to $80.70–86.25 per kg of uranium with this fiber, which is similar to the uranium spot price of $86.68 per kg of uranium

and

    suggests the possibility of economically producing nuclear fuel from the ocean.

Not to disrespect their work, many small scale lab tests confidently assert that costs could be reduced and might possibly be economic.

The fine print is that so far no pilot plants exist and no estimates on the capital plant costs for industrial scale extraction to achieve the possible unit throughput prices as yet exist.

This may yet happen.

There may also be a slip between paper and industrial plant at scale.

> This may yet happen.

Yeah. But probably not for a long time as Uranium from present sources is cheap (enough) and plentiful (enough) and if that should ever get more expensive we can start looking at the huge stockpiles of 95% unspent fuel that we call "nuclear waste". Burning that would (a) give us a lot of electricity and (b) reduce the radioactivity of whatever is left dramatically.

To be clear: I'm not arguing for one or the other, I'm pointing out that one of the above statements doesn't align with the other.

If the other costs are equal (remember I said if) then extracting it from seawater would undoubtedly be easier overall simply because of abundance, and the non-destructive nature of collecting it would mean there's no issue with environmental challenges due to the destructive nature of mining.

Not really. If the costs are equal, then there is no point in investing in a new technology, new plants etc. that don't provide a competitive advantage.

What's the startup question again?

What about your new product is 10x better than the incumbent?

Not sure too many VCs have advised companies as follows: "Hey your new product is exactly as good as the incumbent, you have an absolute winner on your hands here. Where do we need to send the check?"

> What about your new product is 10x better than the incumbent?

Well let's just ignore the idea that mining megacorps operate in any way like a startup does. At the top of the uranium mining food chain, even a 1% reduction in costs (or increase in extraction) would be add around $13M a year to their revenue, so fuck it lets play hypoethetical.

If someone came along and said "hey we have a startup that's exactly as profitable as YouTube, but there's essentially no risk of people protesting our business and using ad-blockers to deprive us of revenue" the VC vultures would be on that shit like a fat kid on cake.

As I said before: seawater is ubiquitous and for the purposes of human scale, essentially limitless everywhere, unlike mined uranium which to be cost effective, is only mined in certain areas where the return is higher.

1. Not lower cost, same cost. Maybe.

2. Who said anything about no risk?

> The vast majority is financing.

The financing for nuclear is expensive primarily because:

1) The costs of construction are so high - so huge amounts of financing needed.

2) The amount of time before investors see any ROI is very long.

A long time ago, when electricity markets were fully monopolized end to end, the long-term ROI on nuclear and other generating assets was guaranteed by the government, and the financial risk was borne by society.

Now, electricity markets have been liberalized (at least at the generation level). Simultaneously, far less capital-intensive generation technologies have been created (renewables, combined-cycle gas, and increasingly storage). These technologies provide an earlier ROI for risk-averse capitalists.

And as Bent Flyvbjerg mentions in "How Big Things Get Done", projects that last for a very long time are all but guaranteed to encounter one or more black swan events and/or recessions.

Bent makes a sensible argument for SMR reactor technology in that book too.

So we moved from using Twitter as a source to TikTok? We live in dark times...

You can also get the same information from here, which has an extensive reference section at the bottom. Disclosure: I wrote it.

https://whatisnuclear.com/nuclear-sustainability.html

Nice work. Do you know of any studies looking at the cost of powering the world that way? And the time need to transition?

I get the old man yells at sky reaction but it's just a short video... A snapshot of information which directly references with overlayed text a citation to the study he's discussing.

Not much different than most HN comments which 90% of the time are only one or two sentences.

None of this is true. Highly upvoted hn comments (the ones people read) bring receipts. This is just someone’s low effort opinion.

For what it’s worth, the cost to extract uranium from seawater is actually a very complicated subject. It is generally cited that the cost is approximately 2x the mining cost, but that’s based on estimates for seawater extraction.

https://www.researchgate.net/publication/280745206_Cost_Esti...

Well, at the very least give a short summary of what you are linking to.

It’s worth noting that the dichotomy you set up isn’t quite right. The land use for solar and wind isn’t an exclusionary zone. The area around a wind turbine can be used same as before (most often as farmland) without a negative impact on its productivity.

And the same is true for solar. In fact, a growing number of agro-voltaic projects are seeing a net positive on crop yields from solar panels due to the increased shading and decreased temperatures.

This reminded me of a solar project at a US airport [0]. They placed solar panels to make a covered parking lot. I think it was part of a larger plan to use panels for cover and/or over some of the vast spaces that the airport covers

"Austin-Bergstrom International Airport (AUS) and Austin Energy celebrate the completion of a new solar panel array constructed on the AUS campus that will produce 1.8 megawatts of locally-generated, renewable energy. ... With 6,642 solar panels spanning across a distance that is equal size to two football fields, the array on the top floor of the airport’s Blue Garage is the largest on-site renewable energy installation on the AUS campus. The panels offer shaded parking for Blue Garage customers and will generate enough solar energy to power up to 160 homes per year."

[0] https://www.austintexas.gov/news/austin-bergstrom-internatio...

I was thinking of you set the solar up high, to create a diet of canopy, then you might be able to grow a rain forest under it which doesn't like direct sunlight and would allow animal habitat...?

Is it possible for solar panels to be semi-transparent so crops can still thrive underneath?

Yes it is: https://www.pv-magazine.com/2021/07/02/transparent-solar-pan...

“Combining two usage modes based on Insolight’s optical micro-tracking technology, these modules focus light on high-efficiency solar cells,” Insolight said in a press release. “When aligned, the optical system can generate energy (E-MODE), but it is also possible to unalign it to ‘leak’ the light (MLT-MODE). The solar modules therefore act like a ‘smart’ shade adjusting the amount of light they let through.”

This makes it possible to optimize the photosynthesis of plants during the seasons and reduce the negative impact of high summer heat on the yields and quality of agricultural products, while recovering the rest of the light in the form of electricity. Starting from July, the panels will be tested for four years on a 165-square-meter surface area. They will replace protective plastic tunnels on strawberries and raspberries.

“Dynamically adjusting the light transmitted to the plants paves the way for increased protection from climate variations and possible increases in crop yields thanks to the matching of the light to the needs of the plants and the lowering of the temperature during heat waves via the shading effect,” said Bastien Christ, head of the berries and medicinal plants group at Agroscope.

A similar project using different module technology: https://www.pv-magazine.com/2023/10/31/baywa-re-starts-build...

The logistics of trying to plant, maintain and harvest crops underneath a bunch of solar panels while also needing to deal with the subsequent issues of uneven runoff of water from rain make it seem impractical. Just cover parking lots, malls and supermarkets with them, we have plenty of those, and they're closer to where the electricity is needed than agricultural land.

Regardless of your opinion on this subject, agrivoltaics projects are being installed today at an increasing rate, and they’re going well, from what I’ve read. It’s not some theoretical proposal, it’s happening now. It’s likely that solar panels will be installed both in parking lots and over farmland.

You can make up whatever you like, saying "seems". Facts are better.

The fact is that agrivoltaics has been very successful, for reasons you probably would not guess in a wholesale void of facts. Looking up the facts, you could actually learn something.

We absolutely should cover those, but there is a lot of farmland. There may not be enough "mall-land"

Well, when i see solar panels atop every mall and commercial building, when every home has a solar roof, then i'll entertain chopping down wilderness or sacrificing farmland to the cause. I still see plent of bare rooftop to address first.

The home roofs are going to be done off the more expensive solar installations ($/kW) that we can build because they’re so small.

It’s also fascinating how quickly the Nirvana fallacy shows up when it’s time to talk about renewables. Supposedly chopping down forests for solar (which isn’t the main way of getting land) or the farmers choosing to put something on their land is top of mind. But chop those forests to make something else, or have the farmers grow super subsidized corn and there isn’t a peep.

Literally nobody proposes "sacrificing" farmland.

I'm looking at a legal agreement on my desk to lease 120 acres of productive eastern Nebraska farmland to build a commercial scale solar project. The land would be taken out of production ("sacrificed") for the 50 year lease, with payments about twice what the land leases for for agriculture (soybeans).

It is very common. Farming is hard, margins slim at best. And farmers are given great leeway in how they may make money from land. Regulation is lax. Many fields have been turned from the production of food to the production of electricity, while countless factory rooftops sit covered only in tar and asphalt.

As soon as we stop using farmland to grow energy crops when the same area could give us 20x the energy using solar panels.

Well good job it's not your decision to make then.

If the economic benefits of adding solar to their farm outweighs the costs then farmers will start adding them to farms.

That's not needed, just have gaps between the panels so they provide partial shade. Many food crops can't tolerate "full sun" well, and will grow perfectly fine even with partial illumination.

I want to make clear that I am not arguing against solar. My belief is that nuclear is an important piece of a much larger puzzle. Wind is not reliable, and for solar to match the figures you provided, we would need to figure out storage, so lets diversify our portfolio :)

Figuring out storage is hard if you think in terms of Lithium Ion grid-scale batteries, or mountains for pumped hydro, but[1] puts forward the idea of synthetic natural gas generated by solar panels. That can be pumped into existing national gas grids, existing gas storage, and sent into existing gas power stations to generate power in quiet times. The article says that solar power has dropped from $100/Watt in 1976 to $0.50/Watt by 2016, and that instead of slowing down as the low hanging fruit has been picked, that process is speeding up since 2011 when Solar started to become cheaper than other forms of power generation, which changed the feedback loops and is bringing in much more demand which brings more investment, research and production, than before when it was an expensive little-used alternative.

This is a linked graph of solar growth compared to International Energy Agency's World Energy Outlook predictions: https://rameznaam.com/wp-content/uploads/2020/05/IEA-Solar-G...

In each of 2006, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2018, the IEA predicted deployment of solar would stop accelerating (line going up) and steady off into consistant growth (flatline on that graph). Every year they have been very quickly wrong, and the 2019 predition of flatline is so wrong that by 2021 actual production of 190GW was WAYYYY off the top of that chart. At this rate we may not need to figure out storage nearly as much as we think.

> "What people have missed is that reaching cost parity on fuel synthesis will unlock huge new demand centers [and trigger an acceleration in demand/investment/research/cost decline of solar created synthetic fuels]."

[1] https://news.ycombinator.com/item?id=32197012 (article rather than comments)

Sure, if it pans out. I'm all for syngas if it can be produced somewhat efficiently at scale. But right now lithium batteries and hydro are proven technologies that can be utilized. That's the difference.

If the story I link below is real, synthetic propane could become the standard for energy storage. Extremely efficient production from electricity and direct fuel cells convert it back even more efficiently. Hank Hill would be so proud.

https://news.ycombinator.com/item?id=37218727

Nuclear would be the worst technology for filling temporary gaps in the production of renewables. The ramping speed of nuclear reactors is limited, and they cannot be throttled below 40% output without shutting them down entirely for quite some time. On top of that, the main expense of nuclear reactors is building and maintaining them, so throttling a reactor is not reducing the costs. You really want to run a nuclear reactor with a high load.

French NPP can vary their power output 80% up or down in 30 min (https://fr.m.wikipedia.org/wiki/Production_pilotable_d%27%C3...)

Fine, than they can go a bit lower still. But for a grid mainly powered by renewables, they would have to be able to go all the way down to 0, what is really not a practical option for nuclear reactors.

But there is another catch: nuclear is extremely expensive, even when run most of the time close to 100%. But any time you throttle the reactor, you are driving the costs up. Because most of the costs are in building and operating the reactor, less so in fuel.

> Wind is not reliable

I think what you mean is that wind alone is not baseload, not that it is unreliable. It is quite reliable in that its availability is predictable such that it can be coordinated with storage to create virtual baseload. Therefore its failure modes are relatively mild in impact.

In contrast, large centralized plants (whether combustion or nuclear) have far more consequential failure modes - for example, losing 1GW of power with little notice, as can happen with these plants, is usually a grid emergency event.

Compression of air in underground cavities

> Hydrostor, which is based in Toronto, is one of several startups working on fixing those problems. The company says it’s figured out a way to capture and reuse the heat generated when air is compressed, eliminating the need to burn gas. It’s also figured out a way to make the mechanics work in areas where caverns must be dug out of hard rock, rather than salt. <

https://www.latimes.com/environment/newsletter/2023-01-12/th...

The more I think about it, the more I'm starting to get of the opinion that this entire call or worry about "storage" when it comes to solar is a giant distraction.

This first thing we need to do is align the costs and incentives. What I mean by that is simply allow the market, or government, to dictate the real cost of providing electricity at night. If there are no solar panels (nighttime), and whatever grid-scale batteries are available cost 1$/kwh then so be it, charge that amount to the consumer. People will learn to forego "bathing" in electricity at night endlessly. For decades we've been spoiled with ridiculous "energy on a tap" that just gives us oodles at the flick of a switch, and we just need to take that away.

As a side-effect of this whole "switching off the endless tap", micro-grids are the future. Small communities with mini-grid-scale batteries and sharing of electricity will take over this stupid "national synchronized grid" idea that has gimped our ability to be agile wrt local energy generation.

"People will learn to forego "bathing" in electricity at night endlessly. For decades we've been spoiled with ridiculous "energy on a tap" that just gives us oodles at the flick of a switch, and we just need to take that away."

I take it you live somewhere warm in the winter. We are already looking at removing other heating options like propane and natural gas furnaces, coal and oil heating is mostly phased out, and burning wood isn't great for the environment either. So electrical heating is necessary anywhere where its normal to freeze for several months. Telling people to stop bathing in electricity at night when that what keeps them alive is bullshit.

"micro-grids are the future. Small communities with mini-grid-scale batteries and sharing of electricity will take over this stupid "national synchronized grid" idea that has gimped our ability to be agile wrt local energy generation."

Why don't you ask Texas residents how not being part of the national synchronized grid worked out for them 2 years ago?

Storing heat for a few hours can be done pretty easily and cheaply though. Indeed many houses already have technologies like water tanks and storage heaters that do this.

It's normal in many very cold places to entirely switch off your heating overnight.

You heat your home up during the day and evening, and as you retire for the night it's switched off. With sufficient insulation and warm bedding you don't need active heating overnight.

So it's absolutely compatible with an electric supply that's heavily biased towards the daytime.

The cold places are usually extreme latitudes.

I live around 60 latitude and here during the winter it might not be even that cold (tho it can be -20 or -30C).

It’s that the amount of sunshine hours and the angle it shines at means that for about 3 months the PV production is essentially zero.

This is during the time the demand is highest.

As an example, it may start becoming more economical to include heat-batteries (I forget the name) in house construction such that they retain heat and radiate it to maintain a not freezing ambient temperature inside a house. That, along with insulation, and some rather moderate changes to behaviour, could entirely eliminate the need for electricity-use during night time hours. We don't know what ingenious and wonderful things people may do when the real-cost of electricity at night is exposed to them.

Ya that's a level of unmitigated bull** where I live there is usually several days out of the year where the temperature is -40 (doesn't matter the units at that temperature it's the same) and massive wind chill. There's not really a reasonable way to heat a houseduring the day and have it remain warm with tempratures like that without major changes to the way houses are built.

This seems like the quintessential example of some Cali tech bro nor understanding that there is anyone outside of their little bubble and assui everyone just lives like them.

Perhaps a Cali tech bro, maybe a standard scandanavian in a passive energy house with tight seals, good insulation, triple glazing, large solar heated hot water tank to hold thermal energy during the night, etc.

There are people outside everbodies particular bubbles.

What percentage of the world's population lives at a place that goes to -40C ever in the year? That's like 0.000001% of the world's population (didn't confirm, thumb sucking).

I think you need to admit, "bro", that you're far from a standard case and that maybe you should suck it up and move to a more hospitable spot instead of forcing the rest of us to subsidize your extreme lifestyle choice at the expense of our environment which we "all" apparently care so much about.

At least I'm suggesting insulation, and alternative methods of heating as opposed to just saying we should chug gigawatts so your butt could be warm at -40C outside.

> "Telling people to stop bathing in electricity at night when that what keeps them alive is bullshit."

I never said anything of the sort. You're taking a really bad-faith and extreme straw-man of what I said, and I refuse to participate.

Well, for one I (and I presume many other people) would not vote for a platform with such an extremist position.

Yes, imagine there was a governor whose position is "at night, everyone will be limited to no more than 100W." The best-case scenario for the governor would be that they're recalled quickly.

It would be more like "at night (or when there is little solar), you pay progressively more for your electricity." A lot of places do that already, you just do it to a slightly-palatable level instead of to the true cost. Partly because of, as you guys point out it's politically nonviable, but also partly because it's electricity from cheap coal as opposed to green solar + super expensive batteries.

>For decades we've been spoiled with ridiculous "energy on a tap" that just gives us oodles at the flick of a switch, and we just need to take that away.

Why shouldn't I be able to have oodles of energy at the flick of a switch?

Why is it bad that people had more than 100 years of using energy at a reasonable price point? Why do you think it's good for the energy to become more expensive or not to be available at all?

We do need energy for everything.

As you're asking, the bulk of the world's population survives with a much lower energy per capita usage than, say, a median US citizen.

For the high energy consumers it's more a perceived need than an actual need.

Further, energy availability appears to work akin to road availability; if you build a six lane highway traffic expands to fill it.

The obvious reason for wanting lower global energy use at this particular point in time is reduce the still increasing by products of energy production, greenhouse gases.

Once the climate parameters return to safer values energy production without those side effects can expand .. while we look at addressing the unwanted toxic by products of our new sources of energy - less greenhouse gases, more acids and waste associated with nickel, copper, lithium, et al.

The future is the macro-grid: use electricity in northern hemisphere while it's summer in the southern hemisphere.

Pardon me, but there's zero future for the micro grids.

> Wind is not reliable

Surface wind is not reliable. I've seen proposals to put turbines on large kites or gliders tethered to the ground. There's pretty much always strong winds over most of the United States somewhere between the surface and 10000 feet.

Hmm what to do with the torque from the windmill though. Perhaps it could have counter rotating propellers to cancel it out. Otherwise it would entangle itself in the anchoring cable.

Also, a failure scenario would mean tonnes of windmill crashing down from high altitude. Hmmmmm

> Also, a failure scenario would mean tonnes of windmill crashing down from high altitude. Hmmmm

10000 feet is less than 2 miles. Even in high winds it wouldn't get more than a a couple or miles or so before hitting the ground.

There are plenty of places in the US where you could fly where it would be centered over a 6 mile diameter circle that contains no people or valuable buildings except for people and buildings that are part of the power facility.

40 million acres are used to grow corn for ethanol. This is 162,000 square kilometers. This can produce 3.24 exajoules of energy.

Also, solar panels don't need any land. There are so many places we can install solar without 'consuming' land. They can be roofs, floating on tops of lakes and reservoirs with the added benefit of preventing evaporation, agrivoltaics combined with farmland, vertical panels, superfund sites, deserts, along the highways, etc.

For all the concern about land use for renewables, it really feels like subsidized ethanol has got to be the most wasteful use of energy investment dollars in terms of farmland used and every other possible metric. It's very interesting to think about using that money and land for other energy generation uses.

One counter point is that these fields can easily be turned into crops to feed the citizens of the country in an emergency. Solar panels not so much. Also, there was already infrastructure in place to easily maintain this energy source.

Not saying this is a reason to keep the subsidies, but I'm sure it made sense at the time.

yes, biofuel is a colossally bad idea and it should have been obvious to everyone involved right from the start.

>"or more square kilometers of land [...]"

Technically you need to factor in the fact that a nuclear plant can be built relatively near the places where its power will be consumed; some mass of solar power in Nevada is highly inefficient for powering New York or Virginia, even if you built HVDC lines to cut down on total line losses, so you'll need to pick land tracts reasonably near battery banks that would in turn be near cities.

Just as well New York and Virginia have oodles of open ocean right at their doorstep to run multi-gigawatt wind farms I guess huh?

Wind isn't reliable.

Yeah and all those people on the other side of the Appalachians can just take a hike, why do they need power anyway. They brought the problem on their selves with their dirty coal mining habits time for them to pay the price.

The comment I replied to talked about getting power from Nevada to New York. I'm not American so I had to look at a map but it seems like the other side of the Appalachians from New York is... Ohio?

Is there something about Ohio that means they have no atmospheric wind nor natural sunlight?

Inventing imaginary problems does not contribute to the discussion. Please use facts.

> If we covered an area 10% the size of Arizona in solar panels

And what are the various Friends of Rare Bugs and Small Furry Animals groups doing in the meantime?

I joke, but even I would balk at the environmental impact of that. Certainly it's going to be greater than any equivalent nuclear installation.

> Of which 0.72% is U-235

Fortunately we're not limited to U-235. With breeder reactors, there's enough nuclear fuel to run human civilization for billions-with-a-b of years.

Cover 4,000 square miles of the USA in surface car parks[1] and that's freedom. Suggest covering 11,000 square miles of desert in solar panels which don't stop land being used for grazing or crop growing or insects or wildlife, and that's environmental distruction that "even" you would balk at.

[1] https://www.archdaily.com/976069/when-5-percent-of-the-unite...

Speaking of parking lots, it's not a terrible idea (and it's already been done before) to put solar panels above parking lots

False dichotomy.

The people who will be screaming about covering the desert with solar panels are exactly the same people who scream about covering the land with car parks.

Exactly.

The only energy source radical environmentalists like is one that exists only in a fantasy. As soon as it starts being built, it becomes evil.

Note that they're already up in arms about windmills killing birds.

Also, covering the desert is definitely going to change the local environment. At a minimum, every joule that goes into the power transmission lines is a joule that will not be available for use by the desert ecosystem.

The desert ecosystem wastes almost all of its incoming joules. The most valuable commodity in a desert is shade.

If you were a cactus you'd no doubt disagree.

And you have discussed this with a cactus? Or are you still just making things up?

The thing about mineral reserves is that they only make sense when you add the price-point to the number.

There is enough Uranium on the planet for a few centuries. Make it a few millennia if you breed it, and lots and lots of millennia if you expand your reactors to use other fuels. But most of it is way more expensive to get than what we use today... what actually makes very little difference for the final costs.

One kg of Uranium is significantly easier to transport compared to the solar energy obtained in a corner of Arizona or Utah though.

And what happens when it gets dark? Solar is cheap, storage is not.

I remember reading some article that said we could offset all of human emissions by painting Vermont stark white or something along those lines.

Covering a desert in solar panels seems like the exact opposite of that plan.

If you ignore all other variables, then of course the situation looks like what one variable would make it do.

Would covering a desert in solar panels cause more thermal solar absorption in that area than would otherwise happen? Yes.

But if we're optimizing for "offsetting the heating effect of human GHG emissions", then installing 4.5TW of solar (about 4x what has been installed worldwide to date) would have a much more positive effect.

The world currently has 1.1TW of solar installed, producing about 6% of all electricity. So our new installation would be on its own capable of supplying 25% of global electricity usage. The corresponding drop in GHG emissions from the shutdown of coal, gas, and oil power plants would far outweigh the fact that part of the desert has been turned black.

> Would covering a desert in solar panels cause more thermal solar absorption in that area than would otherwise happen? Yes.

This depends on the efficiency of the PV modules. When it's greater than the albedo of the desert, it will cool the desert, not warm it. Remember, the electrical energy produced isn't heat. It's turned to heat at the consumer, but that's true of electrical energy from a nuclear plant too. Oh, and did you know that nuclear plants also add 2x as much heat energy in the exhaust of their cooling system?

Has this actually been quantified? Earth's albedo is a critical factor in the portion of the sun's energy that is rejected into space, just as GHG incidence in the atmosphere is.

In theory, darkening a portion of the Earth with high albedo (snow, sand) is worse than darkening a portion of the Earth with low albedo (roads, roofs, forest). Then it should be better to use a greener area for solar panels so long as the capacity factors would be similar.

Millions of square kilometers of the arctic are being "darkened" by loss of sea ice. Nothing humans can do can approach even a tiny fraction of that.

Many people would argue that humans did cause this loss of sea ice.

Also I don't see how that justifies adding to the effect? Especially if we don't know can't compute the trade off? I'm sure someone has done that work but my it didn't immediately jump out at me during a cursory search.

Just the uncertainty in the ice cover prediction is orders of magnitude larger than any effect from adding any plausible amount of solar panels.

Inventing BS problems does not contribute to the discussion. Please stick to facts.

If you don't like discussion what are you doing here?

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