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> Bad idea. We have plenty of much cheaper sources of green energy.

Gates basically has dedicated his life to thinking about issues like this. He funds and promotes all the other sources of green energy as well. It's clearly his considered opinion that nuclear energy is going to be an important component, over and above other sources of green energy to actually achieve our goals in an amount of time and at a scale to have a meaningful impact on climate change.

Not to mention we are now finding that some "green" power is actually harmful, such as hydroelectric dams. Nuclear power has known risks, from disposal to potential meltdowns. Some of our other green technologies have things we don't even know the consequences of yet.

> much cheaper sources of green energy

When people stop bragging about how many more jobs green energy creates than fossil fuels, I'll start believing that renewables are cheaper at scale.

> What we need now is a good storage solution

Collocate the new nuclear plants with facilities that (at high energy cost) recapture carbon into dense fuels.

Re green jobs: I think that's meant as a retort to the "what about coal miners?" Argument.

I'm trying to understand your nuclear -> fuel plan. Nuclear reactors already use a storage solution, why are you adding an extra step? Why not combine it with wind/solar?

Edit: Are you suggesting the green jobs would lead to high wages and costs? Don't forget theres no fuel cost with renewables.

> Nuclear reactors already use a storage solution

Hmm, not sure what storage solution you're thinking of? Is there a nuclear-specific means of storing the energy produced for later use?

What I mean to say is: nuclear power is so cheap that you could use it to power carbon recapture, even at the current cost. There are even people working on using direct air capture to create ultra-dense fuel, e.g. http://carbonengineering.com/ . This is surely very inefficient (lots of energy required to recapture a small amount of fuel), but if we powered it using a nuclear plant's off-peak energy, it's effectively a liquid battery.

"Hmm, not sure what storage solution you're thinking of"

The fissile material itself.

Nuclear power is dispatchable to a point, and I don't think its as cheap as you seem to think it is. The scheme might be worth it for producing jet fuel etc, but using fission to generate electricity to generate fuel for short term storage for a generator? Unless it is really efficient, no.

Combined with renewables which aren't dispatchable at all, more likely, but not where I would put my money.

When people stop bragging about how many more jobs green energy creates than fossil fuels, I'll start believing that renewables are cheaper at scale.

These braggarts haven't calculated the labor intensity per MWh (construction + operation) over the full life cycle of utility scale wind and solar facilities. Utility scale renewables are less labor-intensive than coal or nuclear over the full life cycle. The only reason that renewable boosters can tout jobs vs. coal right now is because coal is shrinking and renewables are still growing robustly.

I suspect that natural gas burned in a combined cycle plant may be more labor-thrifty than anything else, but 1) it's not a low-carbon electricity source like nuclear or renewables and 2) it has been harder for me to calculate how much labor is required for fuel extraction; the calculation is easier with coal since quite a few coal burning plants have dedicated mines.

See https://news.ycombinator.com/item?id=13218366 for a labor-intensity comparison of legacy coal and utility scale PV that I worked out previously.

In fairness, I have seen advocates for coal and nuclear brag about the bountiful wages distributed (costs incurred for electrical ratepayers) by their preferred generating technologies, too.

> Utility scale renewables are less labor-intensive than coal or nuclear over the full life cycle

It's hard to marshal evidence for or against this claim, since as you say, the newest renewable technologies are in the earliest stages of their life cycles. It's also hard to defend or refute claims about the cost of renewables at scale, since they're currently such a small fraction of energy production. Are we looking at economies of scale / diminishing marginal costs? Or, how quickly will we exhaust the geothermal sites, the dam-able rivers, and the rare minerals that go into batteries and solar panels?

Projecting the answers to these questions requires a lot careful modeling, extrapolation, and educated guesses. Given the hopes, fears, and ideologies at play, it's very easy to lie with stats here (or for proponents of any given source, to bend the truth in one direction in the conversation about creating jobs, and in the opposite direction in the conversation about cutting costs). Based on your linked post, it looks like you're digging into this rigorously & honestly, so thanks for that.

> how much labor is required for fuel extraction

Plus transportation. Isn't this way cheaper for nuclear, where way less fuel (in terms of mass) produces way more power? And, isn't there a good deal of extraction that goes into creating a solar panel?

Or, how quickly will we exhaust the geothermal sites, the dam-able rivers, and the rare minerals that go into batteries and solar panels?

With present technology geothermal is going to be a niche source. Hydroelectric generation is not, but most of its potential in developed countries is already tapped. When I speak of large scale renewable growth I mean utility-scale photovoltaics and wind.

Neither solar panels nor batteries for stationary energy storage require rare minerals. Lithium ion batteries that maximize energy density, like those in cars and portable electronic devices, usually contain the comparatively rare element cobalt, but this is not required if lower energy density is acceptable. Batteries that stay in one place don't need maximum energy density and can eliminate cobalt. Lithium itself is not rare; lithium iron phosphate is a perfectly fine battery chemistry for stationary applications and requires no rare minerals.

My estimates of labor intensity for renewables do not include storage or overproduction (to diminish reliance on storage). The numbers I've provided are for incremental nearer-term goals achievable without storage, like "displace the 28% of American electricity that comes from coal with renewables." Storage is immature and I'd be piling speculation on top of speculation if I tried to estimate how much storage and/or overproduction a zero-fossil energy system needs, and how much labor that will require. Note that a zero-fossil energy system built on nuclear foundations will need to deal with these questions too eventually; the difference between peak and average demand for electricity means that nuclear reactors too would need to be overbuilt or coupled with storage to take the place of fossil peakers.

I think that nuclear power is quite safe enough, certainly safer than continued fossil combustion. I don't have any grudge against nuclear apart from the high costs and unpredictable schedules that have attended attempts to build new units. 15 years ago I thought it was obvious that building even the cheapest solar farms was a more expensive way to generate electricity than building an average nuclear reactor. But the numbers changed, and I changed my mind along with them.

Very interesting, thanks. I too would like to see "utility-scale photovoltaics". So...what is the limiting factor in producing new solar panels? A raw material, or well-lit land near population centers, or political will, or what?

World capacity for the production of new solar panels is significantly under-used right now. There are no raw material limits in the short-medium term[1]. The rate of expansion of solar production is limited more by demand than supply at the moment.

Some countries have dense populations and poor availability of sunny land, like Belgium and the Netherlands. The US has better sun and lower population density. There is some resistance to retiring coal from people who make money from coal. But generally speaking solar has always had a favorable public image apart from the high costs -- and the high costs are now turning into moderate and even low costs.

Since large cost reductions have been so very recent, it's just taking a while for everyone to catch up. Just this month Florida Power and Light surprisingly announced plans to build more solar power than any other regulated utility in the world, for example:

https://www.greentechmedia.com/articles/read/florida-power-a...

Their first large-scale solar project was a 25 megawatt facility built in 2009. Last year and this year they're adding solar capacity of about 300 MW per year. With the "30 by 30" announcement they apparently want to accelerate that to beyond 1000 MW per year.

[1] In the long term, manufacturers will have to stop using conductive silver pastes to make cell contacts and switch to more abundant base metals like copper, tin, nickel, or aluminum. Multiple companies have already used copper metallization instead of silver at an industrial scale so I'm reasonably confident that this eventually-necessary transition will not be too difficult.

Have you considered real estate prices?

I don't doubt any of the stats you cite, but it seems that one of the biggest impediments to solar is the huge amount of area it requires. The real estate costs of putting such plants nearby large population centers seems to be one of the major costs.

Rooftop solar seems to be a good solution, but it's still not economical without generous government incentives.

Anecdote: A colleague of mine is trying to get approval for solar panels on top of a property she owns in a high density area of New Jersey. After doing an in depth cost/benefit analysis, she found it was economical, but only because New Jersey has very large incentives. Roughly 2/3 of the project would be financed by the government either in grants or tax credits.

I have calculated the contribution of real estate prices for California solar farms. The cost of land accounts for a tiny part of large scale PV electricity costs -- less than 1%. But of course California is both sunnier and much less densely populated than New Jersey.

Rooftop solar is not especially cost-effective. It yields less energy per installed watt than large solar farms and it costs multiple times as much per watt to install in the US. If the US could get its permitting and inspection for rooftop solar streamlined and standardized like in Germany or Australia, then the price premium over ground-mount systems would be more like 40% than 400%, and it would be worth considering in states without large open spaces.

Even in Germany rooftop systems are less cost-effective than ground mount systems though the cost-effectiveness gap isn't as large as in the US. I attribute Germany's continued incentives for rooftop solar to a desire to maintain broad societal buy-in to the energy transition. Millions of households and businesses all with their own stake in solar makes for a large and stable coalition of supporters. Just having the legacy energy utilities build their own big solar plants is more cost effective but doesn't give so many people a personal stake in the transition.

Ok, thanks again for filling me in on the details, and nice username btw.

> Well gee that is great for you but what does the taxpayer get out of it.

Green energy anywhere and anytime you need it, not just when the sun shines and the wind blows.

The one major problem with nuclear energy is that mining uranium has thus far been an environmental disaster.

The major problem is that it will take twenty years to build a power station - look at Hinkley Point Power station

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

That doesn't seem like an argument against it? I mean, if fission is the best base load (and I'm not saying it is, I don't know) but it takes 20 years to get approval for a fission plant, seems to me like you do some modeling and planning and then you start building.

By the time you've built your nuclear powerplant germany will have phased out coal by 2038 and people are already complaining that this timeline isn't aggressive enough.

For the price of one nuclear powerplant you could have built 3 nuclear powerplants worth of energy storage this year and over the next 20 years the price of energy storage will drop even further which will make it economical without any subsidies.