Nuclear Commission Approves a Safety Aspect of NuScale Power’s Advanced Reactor | Hacker News Reader

Nuclear Commission Approves a Safety Aspect of NuScale Power’s Advanced Reactor

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160 pointsjseliger47 comments

The headline is misleading, they haven't approved the design yet. However, they've been able to certify that the reactor does not need a certain standard of backup power supply and electrical circuitry due to the passive safety features of the design. This standard essentially requires that nuclear power plants have a connection to the grid and an on site backup generator to safety systems that are on completely separate circuits from the nuclear power plant electrical generation systems.

Not having to do this makes it cheaper for NuScale to deploy powerplants. And it also makes it easier for them to build powerplants in remote places where a connection to the electrical grid is not available[0].

[0]https://www.nrc.gov/docs/ML1616/ML16169A148.pdf

Thanks, we've revised the headline to use less misleading language from the article.

Edit: submitted title was "U.S. Nuclear Regulatory Commission Approves NuScale Power’s Advanced Reactor".

When you do this would it be possible to include the old headline in your comment?

Without it comments like the GP are harder to understand what exactly they are speaking to.

FWIW, you can often find this by going to the Google cached version of this page (in this case: "U.S. Nuclear Regulatory Commission Approves NuScale Power’s Advanced Reactor"), though I agree, it would be useful to include.

We usually do. I'll add it above.

Nuclear power buffs should be pleased. This is the first positive step forward for nuclear power for as long as I can remember.

50MW of power is powering roughly 50K homes for a year. It'll probably be for industrial usage at first, but either way it will take pressure off the power grid, and probably make the grid more resilient to boot.

It's difficult to imagine a catastrophic failure scenario for these since they don't require mechanical pumps. But, I'm guessing there's some industry folks here that have more of a nuanced read on this.

(edit: yay Oregon!)

> 50MW of power is powering roughly 50K homes for a year.

50MW is instantaneous power, not power drawn over a period of time.

Ok, I'm off a bit. It looks like 25K homes according to this : https://en.wikipedia.org/wiki/Domestic_energy_consumption

You were close enough the first time. For US households, annualized, 1 kilowatt of electrical demand is about right. The rest of it is fuel-based heating (natural gas stoves/furnaces/water heaters, some oil/wood/coal based heaters.)

https://www.eia.gov/tools/faqs/faq.php?id=97&t=3

10766 kWh per year is ~1.2 kW continuous.

> 50MW of power is powering roughly 50K homes for a year.

This may seem pedantic, but the relevant measure is power when speaking of generators, like this reactor, and energy (in addition to power) when talking about storage, like say, the Tesla battery in Australia. So "...powering roughly 50K homes for a year" could just as well be for a second, a week, or a decade. Indicating a time interval is not meaningful in this context.

Power is the rate of energy consumption/generation (think water flow rate at the faucet), while energy is the total amount stored or consumed (how much you have in the bathtub). Mixing up power (W) with energy (Wh) is unfortunately a pervasive mistake in the media, too; we should strive to avoid it, lest we contribute to the confusion.

(Also, 1kW per house is probably too little; somewhere around 3kW is probably closer to reality.)

Average draw in the US is ~1200 watts.

https://www.eia.gov/tools/faqs/faq.php?id=97&t=3

Canada is similar and then most other places are ½ or less.

> Average draw in the US is ~1200 watts.

Peak draw is more relevant, though, than average draw. My point was that in a hypothetical town with a single 50MW generator you cannot sustain 50k households, due to daily peak usage exceeding the average by a significant factor.

Edit: on reading your reply, you're right.

I think for nuclear the average draw probably is at least equally relevant. Reducing output costs money, so it isn't really going to follow the load down.

As energy storage becomes more prevalent in the coming years, peak load becomes less relavent.

Once you add storage, you really can supply 50k households (consuming an average 24kWh per day) from a 50MW supply.

But then you have to ask which is more expensive, the storage or the excess capacity.

Particularly if demand is synchronised, meaning those peaks can be rather sharp: https://en.wikipedia.org/wiki/TV_pickup

You could defend the "per year" number by pointing out that power needs for homes vary a lot by season, so averaging over a year is the best long term measure.

But of course that means one of these reactors isn't the perfect plant to heat a city of 50k homes, since it would be underpowered part of the year and overpowered other times.

50MW per reactor at 12 per plant is 600MW. Or 600k homes powered by a single power plant. Nuclear is now very safe, and cleaner than coal. I am glad this project is moving forwards.

EDIT: Opportunities for more skilled jobs is always a plus too.

> cleaner than coal

It's also cleaner and less carbon intensive (12 gCO2/kWh) than pretty much everything else out there. Wind beats it as the least carbon intensive (11 gCO2/kWh).

Original reference: https://www.ipcc.ch/pdf/assessment-report/ar5/wg3/ipcc_wg3_a...

Writeup with plots: https://partofthething.com/thoughts/a-medium-length-primer-o...

How is the long-term waste handled?

transferred across our roads, rails, rivers and then returned to earth with a sign that says stay out forever. These are not points to ignore when talking about the benefits of using this process. I haven't read the reports, hopefully the accounted for that extra co2 from disposal processes, clean up and recovery.

Modern transport and disposal techniques are much safer than the transport and disposal of many other industrial chemicals/waste both due to the nature of the waste as well as precautions taken. And disposal cost and carbon footprint are absolutely accounted for in all studies/reports worth their salt. I'd be totally fine having the spent fuel buried in my backyard (in typical/standard disposal canisters) and drinking well-water pumped from below.

I am a nuclear engineer FWIW.

Given it’s not pumped into the atmosphere to be finely dispersed globally and stored in our childrens’ bones and lungs, almost any solution beats the status quo.

That's already changing very rapidly. "World coal production fell by 6.2%, or 231 million tonnes of oil equivalent (mtoe) in 2016"

What changed is both solar and wind cost less than coal. So, coal is being fazed out about as fast as alternatives come online. Give it another 10 years and the landscape will look very different.

The majority of coal displacement in the US has been natural gas which is cleaner from a lung disease perspective but just as bad for climate change.

Actually LNG is 30% less CO2 per unit of energy which isn't revolutionary but it's not a tiny difference either. If a lot of things that currently burn other hydrocarbons (such as ships) would instead burn LNG we could cut emissions quite a bit.

https://en.wikipedia.org/wiki/Liquefied_natural_gas#Environm...

But then you have to account for methane leaks from pipelines and account for the fact that methane has 60x more warming power than co2 and they end up being basically a wash. Consider the error bars in, i.e. https://partofthething.com/thoughts/wp-content/uploads/ipcc-...

Data from https://www.ipcc.ch/pdf/assessment-report/ar5/wg3/ipcc_wg3_a...

LNG is only ~22% of worldwide electricity generation not not growing that fast, the US energy mix is rather unusual.

Also, from a climate perspective the US is less important than many people in the US assume.

Here's world data.

https://en.wikipedia.org/wiki/File:Bp_world_energy_consumpti...

Natural gas and other fossil fuels are soaring.

First that ends in 2015 and coal is already dropping slightly.

Second, Natural gas is used for both heating and electricity generation. It's heating not electricity production that's driving LNG demand. Further, coal is very rarely used for heating so LNG is mostly replacing fuel oil.

PS: That also ignores the worlds largest uses of energy. Growing plants from sunlight which completely dominates all other energy sources.

There's better data in here [1], page 9, with projections. My conclusion is unchanged. Global warming doesn't care what the energy was used for so it's important to consider the entire energy usage portfolio of the world in these discussions. We gots to decarbonize and we are not on track.

[1] https://www.eia.gov/outlooks/aeo/pdf/0383(2017).pdf

Growing plants from sunlight is indeed a large energy flow. However it's not dominant in our emissions to the atmosphere which are changing the climate. 70% of anthropogenic CO2 emissions are non-plant energy-related. Fact is, we use a lot of non-plant energy too because it's very dense energy and that allows us to do things like drive cars, fly airplanes, and heat homes without destroying the environment. Back when everyone was using renewable plant biomass for heat (i.e. firewood) air quality was getting bad and forests were getting destroyed. It's a very good thing we switched to coal when we did, for the forests' sake, but now we need to totally decarbonize. This means intermittent renewables, hydro, and nuclear.

BTW this book [2] has all the info you could ever dream of about world energy usage.

[2] https://mitpress.mit.edu/books/energy-and-civilization

This is a thread about Nuclear power. Which is rarely used directly for home heating, generally it's just resistance heating after being turned into electricity. Anyway...

Your link [1] is for the United States which as I said uses an unusual amount of LNG. Though if you look at Coal on page 10 it's down (~22 to ~14 = ~40%) from 2006 petroleum is also down quite a bit (40 to ~35 = ~12% drop) it's only LNG that's up but again it's up significantly less than just coal has dropped let alone coal + petroleum.

(pedantic) Plants also dominate our emissions to the atmosphere. They simply also extract carbon from the atmosphere.

I think most projections are wildly off base. In the end it's a combination of economics and incentives which will determine changes and while the economics favor renewable incentives are much harder to predict.

Sure nukes aren't generally used for heating, but in places like Russia and more frequently China, district heating directly from nuclear is very much on the table. And electric heating isn't exactly far-fetched of a proposal either. If we ramped up carbon-free electricity sources like nuclear, hydro, and intermittent renewables we could couple that with more electric heating pretty reasonably.

Damn, you're right that it's US only. Ok [1], page 11. Still only through 2016 though. IRs are the fastest growing but they're still very tiny. We have a lot of work to do to decarbonize.

https://www.bp.com/content/dam/bp/en/corporate/pdf/energy-ec...

In Europe, it's going to a places like the one for Finland. France has similar plans. https://www.pri.org/stories/2017-07-31/finlands-solution-nuc... In the US, it stays at the plant for the next generation to figure out what to do with it. Then that problem gets passed to the next generation.

If anyone finds this interesting the film "Into Eternity" is about the construction of Onkalo, a huge underground nuclear waste store in Finland. It's a nice watch, trailer here: https://www.youtube.com/watch?v=xoUkhOup1C4

How is more skilled jobs a plus? Doesn't the US have an excess of skilled job vacancies and and excess of unskilled people? I would think more unskilled jobs would balance the market out better.

Of course any kind of job is also a cost to the company running the plant, which means more of an obstacle to the adoption of more nuclear power. If we could do it without any jobs, I'm sure it'd be much cheaper and more prevalent!

You can always educate more people. Not only helping the economy, and the people, but also getting side benefits like more informed society that makes better decisions in elections.

> Doesn't the US have an excess of skilled job vacancies and and excess of unskilled people?

Yeah, mostly because of its obsolete education system.

The US has a massive shortage of non computing related technical jobs:

https://nytimes.com/2017/11/01/education/edlife/stem-jobs-in...

There's a lot more about the design from the company in https://www.iaea.org/NuclearPower/Downloadable/Meetings/2013...

Not bad. I do worry about the containment vessel not being much bigger than the reactor. That was part of the problem at Fukishima. When the reactor overheated and turned the cooling water to steam, the pressures were too high and the containment was breached.

Three Mile Island had a big containment vessel, and when they had a partial meltdown, the containment held.

seems like they suggest to put it into a water pool in the ground inside the reactor building.

http://www.nuscalepower.com/images/nuscale_smr_benefits/Righ...

I think the whole idea with NuScale reactors is that if you take away external power and scram the reactor, there's enough water in the pool to handle the decay heat. After the water boils away, the decay heat is supposed to be small enough that passive air cooling will keep it safe.

The containment pressures in a NuScale reactor are supposedly lower according to slides I found on the IAEA website. The containment is initially vacuum and apparently the initial pressure pulse of a pressure vessel failure will be contained and the steam will rapidly equilibriate.

Is there any indication of how long it would operate before needing refuelling or decommissioning?

According to http://www.nuscalepower.com/our-technology/technology-overvi... it would have a refueling cycle of 24 months. I didn't see anything about the expected lifetime of their reactors.

How much does it cost? Who can buy them?

From wikipedia:

The company estimates a twelve-unit NuScale plant would cost $5,000 per kilowatt. In comparison, the Energy Information Administration in 2011 estimated costs to be $4,700 per kilowatt for conventional nuclear power, $4,600 for a carbon sequestration coal plant and $931 at a gas-fired plant or in excess of $1,800 for a gas-fired plant with carbon sequestration.

12 unit = 600kW => 3bn$

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

Re "Who can buy them?" - if you have the 3bn, you will probably be able to afford whatever license you need to buy that thing.

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