Hacker News new | ask | show | jobs
by chaffroomba 657 days ago
>it would be 4-8x or so more expensive than solar/wind

Is that accounting for the renewable's inherent need for very expensive energy storage? Because otherwise you need to build that gas turbine to cover for when sun isn't shining.

2 comments

The current trend is moving from "baseload and peaker" to "renewables and firming".

Peaker and firming are both traditionally gas.

If you think that renewables have an inherent need for expensive storage then you're holding them to a higher standard than nuclear. This is both inaccurate and ahistorical given all the pumped hydro built specifically to complement nuclear.

Though the continued reduction in price of renewables and batteries means they probably already meet and exceed your higher standard anyway (see the recent Fraunhofer report that solar and batteries were cheaper than gas in Germany).

> If you think that renewables have an inherent need for expensive storage then you're holding them to a higher standard than nuclear. This is both inaccurate and ahistorical given all the pumped hydro built specifically to complement nuclear.

It's a different kind of storage. Nuclear generates the same amount of electricity all the time but then there is higher demand during certain parts of the day. You then make up the difference between the baseload and the peak with a different kind of power plant. Typically nuclear is not used with storage at all, it's instead used for baseload with the peaks handled by other types of primary generation, traditionally natural gas or non-pumped hydro that dams a river.

Renewables have entirely variable output, so you need alternative generation with enough capacity to supply the whole grid at any given time, and enough storage to be able to do this for a week or more in the event that renewable generation is low for an extended period of time.

It's the difference between building a grid which is half nuclear and half something else vs. fully duplicating the whole capacity of the grid.

I thought I'd neatly encapsulated this with the "baseload and peaking to renewables and firming" slogan but since it appears we need greater depth:

Typically nuclear/renewables is not used with storage at all, it's instead used for baseload/cheap-n-clean-load with the peaks/firming handled by other types of primary generation, traditionally natural gas or non-pumped hydro that dams a river.

Nuclear can trip out in seconds or be put offline by fault investigations or fuel reloading, so you need alternative generation with enough capacity to supply the whole grid at any given time, and enough storage and or firming to be able to do this for a week or more in the event that nuclear generation is low for an extended period of time (like France the other year).

> Typically nuclear/renewables is not used with storage at all, it's instead used for baseload/cheap-n-clean-load with the peaks/firming handled by other types of primary generation, traditionally natural gas or non-pumped hydro that dams a river.

But we're trying to get rid of fossil fuels. If you have enough primary generation from hydro dams or something else that doesn't emit carbon to reliably handle the whole grid then that would be the entire solution by itself. There aren't enough suitable hydro sites to handle the whole grid, which means only needing half as many (or only needing enough storage to make up the difference against half as many) is quite an advantage.

> Nuclear can trip out in seconds or be put offline by fault investigations or fuel reloading, so you need alternative generation with enough capacity to supply the whole grid at any given time, and enough storage and or firming to be able to do this for a week or more in the event that nuclear generation is low for an extended period of time (like France the other year).

You're talking about an individual nuclear plant rather than the whole grid. One plant out of dozens or hundreds being temporarily offline is not a big deal, and refueling in particular is easy because it can be scheduled for seasons when power demand is lower.

The issue with renewables is that it can be night or cloudy or still across thousands of square miles at once, and then low generation periods correlate across the whole grid instead of being isolated to an individual plant, and happen randomly based on weather rather than having any ability to be scheduled.

> The issue with renewables is that it can be night or cloudy or still across thousands of square miles at once

If it was only thousands of square miles, it wouldn't be a problem at all.

Whole of the UK is about 100,000 square miles, not sure how much more if you also include the offshore areas suitable for wind.

Texas is about 270,000 square miles with the same caveat, and (I think) less interconnect capacity to other networks than the UK.

> and happen randomly based on weather

Wasn't that literally the cause of the French reactors having problems? The national weather causing a correlated output reduction in many reactors at the same time?

> If it was only thousands of square miles, it wouldn't be a problem at all.

> Whole of the UK is about 100,000 square miles, not sure how much more if you also include the offshore areas suitable for wind.

> Texas is about 270,000 square miles with the same caveat

It isn't "only" thousands of square miles, weather events commonly span areas the size of what you're talking about. It's obviously going to be night across the whole region at once. It's occasionally calm across the whole continental United States. Not often, but it happens.

> Wasn't that literally the cause of the French reactors having problems? The national weather causing a correlated output reduction in many reactors at the same time?

It was a confluence of factors, one of which was French law that prohibited power plants from putting coolant water higher than a certain temperature back into the river. When the river flow is low and the intake temperature is high, meeting the regulatory requirement necessitated reducing heat generation, i.e. power output. The same is true for any thermal power plant (e.g. coal or natural gas). This happened following a period of anti-nuclear sentiment that resulted in labor shortages in the industry, causing other reactors to concurrently be offline for maintenance for an unusually long period of time. Obviously you can make any generation system unreliable through mismanagement/government opposition.

The coolant temperature limit is a design issue. There are known designs that avoid it, e.g. situate the plant on a larger river or body of water that would provide enough cooling water even on the hottest of days, or use cooling towers instead of river water.

Conversely, it's not obvious how you design a wind turbine that can provide power when there's no wind.

Looking at this from a historical perspective, Nuclear with other types of primary generation did not generate a highly variable grid. Its a recent phenomena in Europe that has caused spot prices jumps from negative to 2$ per kWh, which the primary blame being put in volatile energy production.

If we are claiming that nuclear is similar to renewables, we should expect regions where nuclear is being decommissioned to have an increase in renewables with no increase in natural gas consumption. This is however not the case. This has been demonstrated by the decommissions of nuclear plants in Germany and Sweden, with fossil fuel emissions being increased as a direct results. To take Sweden as an in-depth example, after the decommission of their south based nuclear power plant the two major natural gas plants in the region went from operating a few times a year to running almost 24/7, only shutting down briefly during optimal weather conditions. They are now the highest source of pollution in that region, and more natural gas plants are being planned for construction. As a result the government funding for the "reserve energy" has increased significantly (ie, fossil fuel subsidies).

Germany's gas generation has indeed been flat while nuclear and coal is being phased out, so I guess you've very strongly proved my point.

https://ourworldindata.org/grapher/electricity-prod-source-s...

I'm also not seeing your claimed Swedish impact in the data:

https://ourworldindata.org/grapher/electricity-prod-source-s...

Also worth bearing in mind that support payments generally are used to keep fossil plants open because they no longer burn enough fossil fuels to earn a profit from energy sales. It's an insurance policy which needn't ever burn any fuel to be worthwhile.

> Germany's gas generation has indeed been flat while nuclear and coal is being phased out, so I guess you've very strongly proved my point.

That graph shows domestic generation falling by more than 100TWh and being replaced by "nothing" -- which is to say nothing shown on that graph, because now instead of generating and exporting electricity they're importing it:

https://ourworldindata.org/grapher/net-electricity-imports?t...

Primarily from France, which is using nuclear, hydro and natural gas (in that order).

In California the lowest yearly demand is ~13 GW. The yearly peak is ~48 GW.

Assume that 3 reactors at a time are in revision during the spring and autumn. This means the "base demand" is 16 GW.

I don't see a material difference in handling 32 GW or 48 GW of dispatchable power generation, assuming the lowest possible renewable generation is zero for the renewable side (which is not the case.)

The other option would be having more nuclear plants and turning them off for large parts of the year. That is incredibly expensive.

All this entails forcing the customers to pay for more expensive nuclear energy rather than utilize cheaper energy when it is available.

In reality the more expensive nuclear power plants are turned off.

https://markets.businessinsider.com/news/commodities/energy-...

You're using the instantaneous numbers, which matters for the peak (because if you hit 48 GW for just one hour you still have to meet the demand) but not the trough (because having overcapacity for a negligible number of hours a year is fine). The real base demand number for California is ~24 GW:

https://www.eia.gov/todayinenergy/detail.php?id=42915

Which is a pretty sizable fraction of 48 (not that 16 wasn't).

> The other option would be having more nuclear plants and turning them off for large parts of the year.

Nobody is going to do this. It doesn't make sense to build entirely nuclear plants. It does make sense to build some more than we have now.

That is the average base demand over a year. Meaning for about half the year it will be less and you have to shut down parts of the nuclear fleet.

Either way, solving a 24 GW or 35 GW on top of ~20 GW something base is about as easy. Nuclear simply does not fit modern grids.

> Nobody is going to do this. It doesn't make sense to build entirely nuclear plants. It does make sense to build some more than we have now.

Exactly. Which is why nuclear power does not fit modern grids, because they will be required to shut down. As is seen time and time again in Europe when no one wants their expensive energy.

> That is the average base demand over a year.

Then it's not clear where you came up with 13 GW, which is inconsistent with the ~24 GW from the Department of Energy.

> Either way, solving a 24 GW or 35 GW on top of ~20 GW something base is about as easy.

Needing 48GW instead of 24GW would literally double the cost, on top of doubling the cost of renewable generation since you'd need an average of 48GW of that instead of 24 to avoid regular use of a backup system which is presumably fossil fuels. That is not a small difference.

> Which is why nuclear power does not fit modern grids, because they will be required to shut down.

There is no point at which they shut down. They provide baseload. You get 24 GW from nuclear, which is the minimum load on the grid. If you also get something from renewables at this time, that's when you charge your batteries for later. This won't get you a week but allows you to do peak shaving. If the load is 48GW and you get 24GW from nuclear and 24GW from renewables, everything is fine. If the load is 48GW and you get 24GW from nuclear and anything less from renewables, now you discharge the batteries.

And then you only need 24 GW of peaker plants in the event that the batteries are dead and current load exceeds current generation.

Or the cost of processing nuclear waste for 1,000s of years?
I don't know about this particular power plant, but on new constructions all costs, including decommissioning and storage of waste, are included.
"Storage of waste" is also a farce. All of the components of "nuclear waste" are commercially valuable, especially the exotic and hazardous ones. The issue is that we don't reprocess most of the spent fuel for political reasons.
That is not true, stop perpetuating that myth. Most of the nuclear waste by volume is of low level waste (90%) or intermediate level (7%) and only 3% is high level waste i.e. spent fuel. We still have to store the 97% of waste that cannot be reused.

https://world-nuclear.org/nuclear-essentials/what-is-nuclear...

If we're getting real and addressing "myths" then here's a good often ignored hard truth;

Most radioactive waste, by weight and volume, is low to mid level raioactive waste and most of that is 'NORM' and outside the nuclear power industry.

    The mining industry also produces large volumes of waste containing naturally occurring radioactive material (NORM)

 ~ https://www.arpansa.gov.au/sites/default/files/legacy/pubs/radwaste/Issues92_woollett.pdf
Two examples of large volumes of non nuclear industry radioactive waste are:

* Asia Rare Earth Sdn Bhd (ARE) in Bukit Merah, Perak ( https://en.wikipedia.org/wiki/1982_Bukit_Merah_radioactive_p... ),

* Lynas Advanced Materials Plant (LAMP), Gebeng, Kuantan.

both as a by product of processing to refine rare earth metals for electronics.

Don't change the topic. We are talking about nuclear power, not rare earth.
Low-level waste is basically just ordinary rubbish. You don't have to store it in a mountain for a million years, it will be indistinguishable from background before anybody finishes arguing about what to do with it. A lot of it is indistinguishable from background to begin with but is legally required to be treated differently because of where it came from.

The people who think this is a problem haven't internalized a fact about radioactivity: Half life is the inverse of radioactivity. The more radioactive something is, the less time before it's gone. Anything with a short half life is not a problem because it will be gone soon; anything with a long half life is not a problem because it's about as radioactive as a banana.

> Low-level waste is basically just ordinary rubbish.

Untrue. You are just making nuclear proponents look bad with your broad strokes statements.

Edit: I am sorry if this came out angry. We need to have a good discussion about nuclear power and it's place in the energy mix. It's clearly losing at this point due to the immense costs associated with it (construction, insurance, decommission, etc.), the risks and the long investment horizon. Handwaving away issues or derailing arguments does not help the discussion.

Look we tried to find a solution for LLWs in Germany with cavern style storage repositories in Asse 2 and Morsleben. Due to many reasons, the costs spiraled out of control and we basically had to switch to overground storage and are in the process of repatriation. The reality is that currently storage of LLWs is expensive (see https://www.oecd-nea.org/jcms/pl_13212/low-level-radioactive...). The cost of treatment of LLW is difficult to specify. So far I have seen no reports that would compare treatment to long term storage repositories. Even with incineration the ashes still need to be stored for some time until they can be disposed.

You said

  *All* of the components of "nuclear waste" are commercially valuable, especially the exotic and hazardous ones.
Which is untrue. Most of it is waste that needs to be dealt with and has no value.