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Some questions jump out there:

What does that amount of solar and storage look like in terms of material used for its construction as well as area occupied once it’s deployed?

What current examples do we have of projects at this scale?

What is the lifespan of the solar arrays and batteries?

What are the operating costs? How many personnel are required for maintenance and day to day operation?

What other infrastructure is necessary to support such a deployment? Transmission lines, buildings, monitoring facilities, security, roads, office space, etc.

What is the construction timeline for such a project?

I don't have exact numbers for any of these questions. However, we know that regardless of the inputs in materials or land, the ultimate dollar cost, all in, is cheaper than nuclear. Take the levelized cost of solar for the MWh coinciding with daylight hours, and the levelized cost of storage during the other hours, and nuclear is blown out of the water:

https://www.lazard.com/perspective/levelized-cost-of-energy-...

Also, the scale doesn't matter, we have built far more than 6GW of solar, deployed more than 24GWh of storage, but it doesn't have to be at one location for these resources. Solar and batteries scale far better than nuclear, because they can be deployed on smaller installations without nearly as much hassle as nuclear. Or they can be sited at one location.

Additionally, part of the bonus of solar+storage vs. large nuclear is that when you spread out your generation into smaller grid sections, then you can reduce the need for large transmission infrastructure that requires maintenance[1].

Distributed software is good, so why not distributed energy generation? Answer: distributed energy generation is great!

[1]: https://www.cnbc.com/2022/01/05/california-finds-pge-equipme...

Even so, when people say that we’ll just spread out this energy generation infrastructure everywhere I still want to know the actual numbers. Are there enough rooftops and vacant lots in LA to provide all the necessary power? What about lower density areas? What about northern climates with lots of snow and rain? There is still maintenance involved, installation costs are likely increased by doing this piecemeal rather than at a single site. Are we assuming all of this will be undertaken by individual homeowners or is it a commercial operation? Leaving it up to individuals seems like it would drastically slow roll out due to a lot of people not being able to afford it or simply being unwilling to have panels. If commercial then the available locations become very limited. These things can’t just be hand waved away.

So, like, why don't you try to calculate this for yourself? As a pedagogical exercise, I think you'll get much more out of it if you compute the numbers for yourself and play through a bunch of "what if" scenarios.

Just to get you started with some ballpark numbers: The solar irradiance at ground level on a sunny day is greater than 1kW/m^2 for about 6 hours per day (google for "AM1.5"). Typical commercial panels have a conversion efficiency of 21-22%.

You seem very confident that solar is impossible, so why don't you make some reasonable assumptions and prove it to all of us?

I didn’t say that I think it’s impossible. I’m asking for the reasoning behind the belief that it would be the optimal solution. In this context a lot of details are being talked about to argue for or against the viability of nuclear but I don’t see the same critical process being applied to the assertions that we can run everything on solar and batteries. I’ve put forward many of the same questions that have been answered for nuclear, it is up to the solar proponents to answer them.

It's safe to assume that most nuclear propositions are based upon unrealistic best case scenarios that won't stand up to the scrutiny of reality, and that all solar propositions have been treated incredibly harshly and conservatively and the solar solution will be completely underestimated.

There is a massive bias in the field in favor of nuclear and against solar, and this shows in every single prediction made over the past 15-20 years. The EIA would uncritically put out numbers for "advanced nuclear" that were unbeliever rosy for a tech that had never been built. And at the same time, use out of date costs for solar, and the assumption that solar would stay at the old prices and never improve in price.

Or you will see peer reviewed papers in nuclear that assume ridiculous rosy solutions, that make it all the way through to publication without those rosy assumptions being challenged. For example, using nuclear in remote areas, but it using the actual capacity factor of that sort of system, 40-50%, and instead assuming that the price is coming from using every last bit of electricity at all time. In contrast all the modeling around solar always picks the most conservative estimates, because of the unrealistic hyper criticism of solar, which leads to even the most rosy of solar predictions being underestimated of solar.

Similarly, "concerns" about land or energy density are not realistic concerns, but mere political talk used to delay delay delay as long as possible the obvious solution that solar will be a cornerstone of our energy future, from 40%-70% of most countries' energy.

But if you actually are interested in the land usage, it's a question that has been studied to death. NREL is usually a good source, but one caution is to look at the date of any publication, and realize that if it's more than a year old, a lot of the data will be out of date. Here's a 2013 report on land use:

https://www.nrel.gov/docs/fy13osti/56290.pdf

There is absolutely no need to use any land exclusively for solar or wind.

Both coexist synergetically with reservoirs, canal, pasture, even crop land. So, zero acres of land needed.

If small commercial solar operations are in fact cheap and have a high return then why am I not seeing startup solar power generation companies everywhere? Surely it would be a hot industry to get into if you can put it anywhere and make a profit?

I would suggest that those companies exist everywhere, you just don't see them. There's something like 1 TW of renewable projects that are being considered in US interconnection queues right now. Total US power draw is only 0.5TW. At and average of ~30% capacity factor, that's 60% of total US electricity demand replacement, with today's projects.

Now, only a fraction of these will get connected, because only the marginal best investment dollar gets the invested, but the scale is there.

Really the limit it current solar and wind production capacity, which is ever increasing at absolutely terrific speeds.

This is one of many reasons that I think a focus on nuclear is the wrong place. It's not going to be able to scale to catch up to these other technologies, even if after 60 years of development, nuclear finds a learning curve for the first time ever.

I’m aware of several heavily subsidized renewable projects in my local area alone that have failed to deliver usable power to a grid that sorely needs it. I’m aware of 0 independently funded ventures even though my area has some of the highest electricity prices in the country.

My question is given this market where you have high prices and high demand, why do I not see any entrepreneurs building small solar installations and cutting deals with municipalities to provide some of their grid power?

That tells me that the technology, cost, and/or regulation isn’t viable yet. Promises of future developments do nothing to address current needs. I have a feeling that 100% renewable generation is fast becoming a “20 years away” problem since I’ve been hearing the same promises for at least 20 years now and those older than me likely remember even older promises.

> That tells me that the technology, cost, and/or regulation isn’t viable yet.

I don't know where you live, but generalizing from one small locality with an out of wack market is leading you to the wrong conclusions.

In places where there's a free market for new generation, like Texas, there's more GW of storage being added than GW of natural gas. There's an order of magnitude of new wind and solar generation being added than natural gas, and this is the place with some of the cheapest natural gas in the entire world. Having trouble finding ERCOT, but for the entire US, 1.3TW of the 1.4TW on newly proposed projects are renewable or storage:

https://www.publicpower.org/periodical/article/renewables-do...

So your local utility, which is charging you high prices, probably has a process that disincentivizes renewables to a large degree. And if there are zero independent funded ventures, then your utility must be actively stopping renewables, and those investors are working in the far more fertile rest of the US.

In particular, small projects can be the hardest to get through. There's zero reason for a utility to cut a deal, they are a monopoly, they are raking in far checks by doing nothing. Utility executives are some of the people least likely to adopt any sort of new technology.

The biggest impediment to renewables sweeping through the grid and giving us cheaper electricity is politics, conservatives, and rentierism. In areas where there's a market set up to allow lower costs to win, fossil fuels are toast. But in most places, electricity is not a market.

Replacing existing operating power plants is tougher than outcompeting other options for new power plants. Demand for grid energy in the US has been flat for more than a decade.

> At today's prices, thay $12B could instead buy 6GW of solar at 20% capacity factor, and 24GWh of batteries.

I don't think that can actually be done. The world's largest battery installation is less than 1 GWh AFAICT. OTOH we're not doing great at nuclear either.

It doesn't have to all be one giant stack of batteries. Your argument is like saying that we can't add more than (say) 2 GW of nuclear, because that's the size of the largest nuclear power plant.

What do you mean by "can't be done"? If we can build a 500MWh battery we can build a 1GWh battery by doing the 500MWh battery two times.

Similarly if we can build a 1GWh battery we can build also a 24 GWh battery.

That's the same argument for building nuclear -- we've done projects before, just do it more/bigger.

Yet we can't and aren't.

I don't think this black and white thinking is really useful. There are inhabited places in the world where solar and wind face real challenges to practicality as the sole source of energy. I would be shocked if we're capable of building an amount of storage that will get the city I live in through the winter, for example. Certainly not for cheaper than a natural gas plant, which is the real competition.

Frankly, whenever this comes up the handwaving about storage just seems hopelessly optimistic even for places where it is practical, let alone places where you're lucky to get 4 hours of sunlight a day for a bunch of the year.

Nothing is ever that simple. If carbon zero is an imperative, then there will sometimes be need for something other than solar and wind, and it will inevitably be "impractically expensive" compared to the carbon emitting sources we're moving away from.

It's certainly important to improve the economies of scale of renewables, but doing so is not the goal. Saving money is not the goal. The survival of the human species is the goal, and we aren't going to get there by nickel and diming our way to it.

Does your city burn natural gas in the winter? That natural gas is not coming directly from wells, typically; it is stored in underground caverns and pipelines. Hydrogen can be stored just the same way. Power-to-X (where X can be hydrogen or other e-fuels) allows renewables to scale to 100% of the energy needed by society at affordable costs.

https://ieeexplore.ieee.org/document/9837910

I mean, nuclear might be expensive, time consuming to build, and difficult but at least we've been doing it for 70 years. It's not clear that projections of long term costs on things we haven't even done at scale are going to be realistic when we try them in the real world.

Even if it takes 20 years to build a nuke, that might still be sooner than "power to x" becomes a viable, affordable option for most of the world.

This is the weird thing about this argument: it so often rests simultaneously on an argument for practicality and/or cost effectiveness, but literally any criticism is met with a gish gallop of unproven technology. You can't have this both ways.

In the end, my central thesis here is just that if you think the be all and end all of this issue is cost effectiveness you are optimizing for the wrong goals and it leaves open a giant window for carbon emitting sources to justify their use when renewables don't work for various local reasons.

The thing to be black and white about is carbon emissions. "What energy mix works for place X right now if we try to eliminate carbon emissions asap" is not a decision that's gonna be made on an internet forum.

You're aware that current commercial nuclear power plants cannot power the world, right? They are thermal burner reactors. Supplying the entire world's current primary energy demand would require about 6000 1 GW(e) (which is 3 GW(th)) reactors. These would use up current uranium resource (not reserve) in about five years.

A nuke powered world will either require radically new sources of uranium (like sea water uranium extraction) or breeder reactors. Neither is available now, unlike cheap electrolyzers for making hydrogen (< $300/W in China).

Please point to me saying anything about "powering the world" with nukes. What a ridiculous strawman. This isn't Mortal Kombat: Energy Edition.

This is all about moving off fossil fuels because of induced climate change. That requires changing what powers the world. If nuclear is not going to power the world, then it's basically irrelevant, and the issues raised against renewables will not block their widespread adoption.

No one thing is going to power the whole world. Even "renewables" isn't one thing, and it can't and won't be deployed the same way in every climate or environment. It, as a blanket set of things, should be deployed everywhere however it can be. But there is no reason to exclude nuclear a priori as a blanket thing. And especially not in favor of waiting for promised improvements in storage or synthetic fuels that have not yet been proven.

Again, this is not a duel to the death. The only thing that should be dismissed out of hand is carbon emitting fuels.

If you live in a place that only gets four hours of sun a day, sure, look more into nuclear.

But instead of being so "black and white" and insisting it must be nuclear that powers things, also evaluate options like thermal storage to gather summertime heat in reservoirs for use throughout the winter. It's super cheap, and makes a ton of sense in most areas, yet it's so low tech that it gets ignored.

I will be black and white that fission is not a feasible solution for the vast majority of the human population for at least the next 20 years, and probably forever. Despite more than half a century of experience, it has not improved as a technology. There would have to be some sort of drastic breakthrough for nuclear to be a realistic power source for most of the earth's surface.

> But instead of being so "black and white" and insisting it must be nuclear that powers things

It sure is a good thing I didn't say anything of the sort or wow I'd be a hypocrite.

I am definitely not the person trying to shoehorn the entire earth into one energy mix box in this conversation. I think the answer to this is likely to vary a lot all over the world.

Also a lot of the world's population is far enough north that winters produce relatively little solar or wind energy. And those places also tend to be massive energy consumers because it's also very cold.

Right now that doesn't show up in electricity stats because of how common in-home gas heating is. In order to decarbonize the northern parts of the world we will need to dramatically increase both electric energy consumption and production, during winter, because heat pumps will almost certainly be replacing gas furnaces.