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Smaller reactors bring nuclear power closer to fulfilling its promise

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91–100 of 257 posts

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#91
post #41

Earlier quoted context omitted.

> Even if its cheaper to build small reactor vessels, MANY of the other costs become more expensive in larger numbers. There is no way SMR could beat solar+battery power cost even now. With sodium and other batteries projected to reduce storage cost, it is even more unlikely that SMR could be price competitive in future grids. SMR is the only way that dying western nuclear industry could attempt to deal with ballooni…

If solar+battery were cheaper wouldn't the new AI data centers be opting to pay to build that rather than nuclear or LPG options?

They are cheaper, that’s why in most of the world, datacentres are being built where there’s copious solar or wind power.

The problem is that they need full power 24/365.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#92

Although generally safe these reactors aren't totally safe. I'm concerned lax physical security will allow miscreants to blow them up and spread nuclear materials over a wide area. The ensuing panic would totally destroy any goodwill nuclear power has gained over the last 20 years or so. I'm also concerned these things will mostly be used by Big Tech for their A.I. data-centers playing the Good Samaritan with their c…

> I'm also concerned these things will mostly be used by Big Tech for their A.I. data-centers Why is that a concern?

I'm also a bit confused by that criticism. If Big Tech wants to use a portion of their ginormous profits to create a much larger market for the commercialization of small reactors, it sounds like a net positive to me. The data center construction spree is basically, in part, a giant private stimulus program for our energy supply. Yeah it's messy in the short run, but considering how much of Big Tech's profits are arguably undeserved, I'll take it over other options if regulatory & legislative actions lack feasibility.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#93
post #74

Earlier quoted context omitted.

To a first approximation, China does not build nuclear power. Nuclear's share of power production in China is 4% and dropping. It seems to me that the main reason China keeps building a relatively tiny amount of nuclear is strategic. Reasons like ensuring they never forget how and ensuring they always have buildable designs so that if something changed they could ramp up the program. And probably even more likely: nu…

But coal is still 49%. The whole point of nuclear in a carbon-free, mostly-renewable grid is to avoid needing enormous amounts of storage and overproduction. That's a need that doesn't come up when you're still half fossil. If you want to decarbonize as fast as possible, it makes sense to focus on rolling out wind/solar/battery as fast as possible for now, but keep developing nuclear technology to cover the last bit…

The coal argument about China doesn't hold water when you look at what they're actually building. Around 80% of their new power sources are renewable, and 10 to 15% is coal. They're aggressively focusing primarily on building renewable -- so to say that their coal is 49% is either misleading or entirely missing the point.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#94
post #34

Earlier quoted context omitted.

Solar and nuclear are comparable: 0.02 vs 0.03 deaths/TWh ( https://ourworldindata.org/grapher/death-rates-from-energy-p... ) Depending on what kind of solar, it can have quite a high death/TWh ratio because people fall off roofs while installing them. As a ratio is far better now that so much new solar is ground level solar farms and not installed by amateurs or professionals who have a van, a ladder and watched a Y…

what about other risks such as the risk of large scale contamination of habitable areas?

Coal is particularly bad about large scale contamination. Nuclear has historically involved substantial contamination in processing plants (Hanford, Paducah, Oak Ridge, Rocky Flats and so on).

Solar, wind, and battery do not have comparable large scale contamination risks.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#95

Although generally safe these reactors aren't totally safe. I'm concerned lax physical security will allow miscreants to blow them up and spread nuclear materials over a wide area. The ensuing panic would totally destroy any goodwill nuclear power has gained over the last 20 years or so. I'm also concerned these things will mostly be used by Big Tech for their A.I. data-centers playing the Good Samaritan with their c…

Well, gas and oil plants are actively emitting pollutants that kill thousands. And nuclear still is the safest energy sort available.

People are far more terrified of flying, in general, than they are of driving. However, driving is far, far more dangerous -- with flying commercial being one of the safest modes of travel.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#96

Earlier quoted context omitted.

> firm That's the opposite of what you want. You want something that is cost-effective to operate at a 10%, 1% or 0.1% duty cycle. Like nat gas or hydro. Not nuclear. And overbuilding isn't the only lever you have to ensure coverage meets your target 99.99% level -- geographic diversity works really well (the wind is always blowing somewhere), and wind power production is usually negatively correlated with solar powe…

You are very wrong. US base load demand is around 400GW that must be provided 24/7

Baseload is a cost optimization strategy only relevant if your non-dispatchable power generation is cheaper than your dispatchable power generation.

https://en.acatech.de/publication/baseload-power-plants/

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#97
post #23

Earlier quoted context omitted.

SMR is driven by funding, insurance, and regulation. China doesn't have these issues and builds conventional at a great price. China is building 37 reactors, only 4-5 are SMR-type units, and are larger at 600MW. The rest are standard PWR, and the 40+ in planning are dominating by standard PWR. Regulatory risk is too high, building too infrequent to understand costs, funding for first-of-its-kind is too hard for nucle…

This is an important point: in a lot of ways, SMRs are a strictly worse than 1000MW plant. The potential financial benefits come from all the other factors you mentioned. I would rather have a "worse" nuclear power plant that actually gets built.

The hope of SMR is that it can be cost-effective at the same level that other factory-produced power sources are. If that's not on the table, then large-scale nuclear deployment mostly isn't going to happen.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#99

Earlier quoted context omitted.

I think you're underestimating the costs and difficulties associated with 99.99% renewables and/or using it as a straw man against the highly inexpensive and achievable 95% renewables. You're also underestimating the costs of using nuclear to achieve 99.99% reliability on top of a grid with 95% renewables: in that scenario you need nuclear capable of supplying ~100% of your power. In which case you might as well ditc…

>in that scenario you need nuclear capable of supplying ~100% of your power. Where are you getting that from? Again, nuclear doesn't need to be a full backup, and nobody is suggesting we ditch renewables for nuclear. A perfectly viable solution would be a grid with a majority of power coming from renewables and storage, with enough nuclear generation to reduce the amount of overbuild necessary and to stop burning nat…

If you're using nuclear as a backstop in that way, you're using the same statistical techniques that let you use cheaper, less reliable sources of power for backstop.

Re: Smaller reactors bring nuclear power closer to fulfilling its promise

#100
post #74

Earlier quoted context omitted.

But coal is still 49%. The whole point of nuclear in a carbon-free, mostly-renewable grid is to avoid needing enormous amounts of storage and overproduction. That's a need that doesn't come up when you're still half fossil. If you want to decarbonize as fast as possible, it makes sense to focus on rolling out wind/solar/battery as fast as possible for now, but keep developing nuclear technology to cover the last bit…

The most cost efficient new-build grid is 90-98% solar/wind/battery depending on your locales insolation & wind coverage. (Source Ember Energy) The remaining 2-10% is nat gas, if you have a piped source, or coal if you don't. But 98% renewable doesn't mean you can hit 100% by adding 2% more of something else, it means your something else has to supply ~100% of the power 2% of the time. If China is aiming for that cos…

And they build a lot of modern coal power station with over 45% efficiency and flexibility in power output.
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