[gwicks56]

People have been hyping up small modular reactors for as long as I have been alive. They make total sense. And yet, there is not a single one is operation? I don't really care what tech gets us to cheap, abundant power, but given the cost curves of solar and batteries, it's hard to see anything competing.

Both are here, right now, and getting cheaper every year. Nuclear seems to be something climate skeptics points to as a way of doing nothing.

[i_am_proteus]

It is probably more productive to talk about why certain technologies have and have not been adopted than to "take sides" in an artificial debate that, for some reason, pits nuclear against wind and solar.

The first small modular civilian reactor in the United States in 2022. However, the United States has been producing small modular reactors for military use since the late 1950s.

Ignore dogma and consider cases why nuclear power might be beneficial even if the dollar cost for wind and solar is globally lower: - The power output variance for nuclear is not very correlated with solar, wind, and hydro. Given the issues related to supply and demand variance, adding power sources whose variance isn't correlated with other power sources stabilizes supply and reduces risks of blackouts. - Solar, wind, and hydro are very geographically-dependent sources. To a small degree, so is nuclear— it requires cooling— but it can be built in places that aren't great choices for wind and solar. This means it's very useful for some local markets. - Nuclear has a different set of mineral requirements from batteries. In many ways, they are more complicated (e.g., enriching Uranium for light water reactors), but they are nonetheless different. Using nuclear alongside batteries reduces risk from mineral supply chains being broken.

Most of these effects run in both directions. Relying entirely on one source of energy is more risky than utilizing an ensemble of sources.

[ncmncm]

Nukes just cost more. Always have, always will. Like geothermal, they depend on a steam turbine that is expensive to maintain. It is hard for anything with a steam turbine to compete with anything without.

Nukes have the extra ball-and-chain of huge capital cost to amortize over all the kWh they will produce over their lifetime. This means that if you end up operating only half time, there are half as many kWh to amortize over, and each kWh costs even more, making you even less competitive. (Operating a steam turbine less might reduce maintenance cost, but probably not if you are starting and stopping it every night, or if you keep it cycling to avoid that.)

So the expectation is that nukes will very quickly become unable to produce enough revenue to pay for continued operation. Then they are mothballed. Suddenly, all that capex is amortized over a much smaller lifetime kWh total, and the actual cost of every kWh ever produced jumps instantly to greater than you ever were able to charge for it. Then you go into receivership, or anyway write off that capex you thought you had invested, but really just poured down a hole.

[jokoon]

In the context of CO2 emissions, money doesn't matter, only resources and physical units do.

[ncmncm]

Money matters in that you can spend it building and operating nukes, or building renewables. You can't spend the same dollar on both, but the dollar spent on renewables gets you more kW than the same dollar spent on nukes.

We will need every non-carbon kW we can muster.

[jokoon]

what I meant is that you cannot only consider money when making choices about energy, you need to consider materials and their CO2 footprint.

prices change, physical units don't.

[ncmncm]

Zero CO2 footprint is hard to beat.

[tuatoru]

Why? OK. The reason why nuclear has not been adopted is that society has taken against it. Politicians respond to what people want, and create rules and roadblocks.

There are alternatives that can fill the same roles you envisage for nuclear. We'll get some of those instead.

Don't talk to us nerds, go knocking on doors and persuade soccer moms and instagram influencers that nuclear is safest, cheapest, best for their kiddies. That's who you need to convince.

[pfdietz]

The people you need to convince are the people with money making the decisions. They look at nuclear and see a loser technology that consistently overpromises and underdelivers, and blows throw its cost promises again and again. In comparison, utility scale renewable installations dependably come in with 10% of the contracted figures.

V.C. Summer and Vogtle 3/4 were the nails in the coffin for nuclear here in the US. Nuclear has no time now to rebuild a reputation for honesty.

Soccer moms and instagram influencers have nothing to do with this.

[tuatoru]

They have votes. Politicians do what they say.

[ncmncm]

Politicians have arranged to be well-insulated from what soccer moms want. Soccer moms, meanwhile, are what we call a "managed population". They vote as they are told to. Not just them, of course.

We are living in the world Edward Bernays built, where democracy holds vanishingly little sway as PR machinery reliably generates votes for whatever whoever pays it wants.

Sometimes opposing payers compete.

[belorn]

We shouldn't assume that pro-nuclear people are climate skeptics, anymore than we should assume that anti-nuclear people are fossil fuel advocates. German renewables politicians voted to get natural gas declared as green, and on the opposite side of the political debate we had nuclear politicians, both accusing the other side of being climate skeptics.

We should not care what tech get us to cheap, abundant, emission-free power, and the current trends from nations around the world points in multiple directions. We don't see examples of cheap small modular reactors, but we also don't have national grids that operates exclusively on solar and batteries. Solar seem to have the best cost curve, while short duration batteries looks great in replacing natural gas when those are used in short (a few hours) duration. Battery technology is also looking great to replace grid stabilizers, ie something to temporary supply or take energy when energy plants on the grid boots up or goes winds down.

Skeptics of solar and batteries is generally directed towards the idea of replacing all worlds existing fossil fueled power plants. Replacing them all with nuclear looks conceptional feasible. Getting the solar capacity up to 100% seems also feasible, but batteries is generally were people start to have doubts.