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Comment by Retric | Hacker News Reader

Nuclear power is extremely expensive and does not allow for peaking power. In the US company's are shutting them down early because operation costs are to high, let alone construction. So, on the surface it seems relatively useless for meeting our long term energy needs.

The only 'advantage' seems to be making money for companies that build or operate nuclear power plants. Thus, there are going to be plenty of experts backing them.

PS: While the carbon in natural gas produces CO2, the hydrogen atoms in it combine with Oxygen to form water making it a lower carbon source than Coal. If the goal is a rather arbitrary 32% lower emissions then natural gas can help reach that goal.

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It actually depends entirely on the design of the reactor whether or not the plant can be used for peaking power.

France used nuclear plants as load followers (their entire fleet). It stands to reason that one could be designed as a 'peaking' power plant if one had the desire.

Nuclear aircraft carrier and submarine design are good at load following and may be suitable for "peaking" with some modification.

Nuclear is expensive when compared to coal/oil/gas, but it's a bit of a catch-22. It's expensive to build a nuclear plant because we don't build very many, so you never get a real economy of scale in the production. Also they're expensive to insure/decommission, so they kind of need to be a state sponsored capital expense.

At what cost? Load following is actually a much easer problem than peaking for nuclear power. Quickly going from 0 to 100% is much harder than 20-90%. This means they operate well as huge chunks of the grid, but don't fit nearly as well into a variable energy mix.

A lot of different things make nuclear power expensive to build and operate. Compared to coal/natural gas they need a lot of extra buildings and much thicker walls etc. Compared to solar they need armed guards, and exclusion zone, regular inspections, etc. Space wise you can grow food in the middle of a wind farm without issue.

It turns out the real problem is not construction costs so much as operation and decommissioning costs, which have little to do with economy's of scale. The decommissioning costs have also gotten much worse as investment returns have dropped. Paying for things 40 years down the line means return on investment becomes critical.

As I said WRT peaking, submarines and aircraft carriers can operate in this 0 to 100% way. Anyway, peaking is kind of irrelevant because it is a minimal section of the grid, We currently have a very limited number of nuclear reactor designs, so its possible that there are other better designs that would be possible with new technology. You have to understand that we're basically using 70s/80s designs in all of the current reactors (even brand new ones). There's been very little meaningful/adopted innovation in the field in the civilian sector.

Agree about the decommissioning costs and operation costs compared to solar and wind at least. I think coal/natural gas/oil have other net negatives that really aren't accounted for economically (tragedy of the commons type stuff that we've never really accounted for economically and are only starting to take in to account far too late).

But agreed, renewables and increasing efficiency needs to be our primary goal from a cost/benefit point of view.

But... if you need a lot of constant base load, nuclear is a good option (better than renewables at least until battery technology catches up and is proven), and would be a better option if we were interested in investing in the technology and science to make it safer and more efficient.

I kind of discount the economic arguments because we NEED low emission power sources. Saying 'well coal/natural gas is cheaper' is missing the point. The choices are almost everyone dies but its cheap, vs more expensive. Picking almost everyone dies is incredibly short-sighted. I'd spend whatever amount of money if it meant we could stop burning stuff. If the government needs to push it through, so be it.

The economic argument is rather persuasive IMO. The nuclear subsides are simply massive and often ignored.

The cost problem with nuclear is not that it's slightly more expensive, it's vastly more expensive. For the same cast you can build a lot more renewables which reduces their variability. Yes, they will often be over producing, but from a cost standpoint that's not really an issue.

PS: As to R&D, not having construction ready designs is a huge problem. If we had 20 years and 100's of billions for risky R&D that would be one thing. But, I think that time has passed.

Coal subsidies are also massive and ignored.

No, you cannot build enough renewable power to replace even a single nuclear plant in most of Europe. In the US, you'd have to build these in the desert to even come close, but maintenance would still make it hard to equal cost over time.

EU already get's more electricity from Renewables than Nuclear power so WTF are you smoking?

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

  Electricity by source in 2014
  Wind: 51.4 TWh (9.7%)
  Solar: 32.8 TWh (6.2%)
  Biomass: 53 TWh (10.0%)
  vs
  Nuclear: 91.8 TWh (17.2%)

Biomass can be used for Peaking power and can fill gaps in wind and solar.

It is true that nuclear power is bad at peaking. That's why no one uses them for that. They are good at base-load power, which is where they are used.

Use the right tool for the job. Different sources of energy have different upsides and downsides and we should take advantage of those. Use wind and solar (possibly backed by batteries) and natural gas as peak load generation because they are good at that. And use nuclear as the base load.

I agree with the premise floated by the 1st expert in the article that we are not rewarding nuclear for its carbon free generation. The reason utilities are closing nuclear plants are because of the deregulation of electric power and creation of power supply "markets". Nuclear has to compete on price alone against cheap natural gas and subsidized renewables (not only are the fuel sources of those cheap, so are the capital costs compared to nuclear).

Re your PS, are you saying that hydrogen atoms in coal DO NOT combine with oxygen to create water during combustion? Because my college education and career as a mechanical engineer taught me otherwise.

Using batteries for grid storage is terrible compared to pumped hydro and on demand hydro.

We agree on the chemistry. The point of my ps is the C becomes CO2 the H becomes H2O, but we don't care about H2O. Which is why hydrocarbons produce less CO2 per watt than coal.

The downside of PSH of course is the massive reservoirs you have to create, but they have astonishingly good efficiency (I was skeptical when I first heard of the concept, but real-world examples can hit an 80% efficiency target which more than makes up for the constant replacement of batteries and the potential impact of sourcing lithium or other materials depending on who is mining them).

I agree pumped hydro is good, but there are only so many places you can site it.

> Which is why hydrocarbons produce less CO2 per watt than coal.

No. It has nothing to do with water. Coal is a hydrocarbon as well. It has to do with the type of hydrocarbon chains.

Anthracite coal is up to 85.7% carbon by weight the rest is not pure hydrogen but a mix of sulfur, oxygen, nitrogen, and hydrogen. (And yes, that Oxygen lowers the energy density while increasing CO2 release.)

Natural gas is 25% hydrogen 75% carbon.

Burning hydrogen produces water not CO2.

So, while the specific bonds play a role the actual carbon vs. hydrogen content is a major issue.

Actually, companies are building more. In Georgia we are building the first new reactors in 3 decades with more planned.

https://www.georgiapower.com/about-energy/energy-sources/nuc...

I didn't know they were bad at peaking but that makes sense.

The way I understood nuclear plants is they are enormous capital expenses and thus a utility is going to shy away from them because of that. I wonder how much they compare to a new coal fire plant though.

Not badly even considering the political issues and expense up front. Maintenance is not that expensive.

Utilities mostly shy away because of politics, not cost.

It seems cost is the biggest issue compared to a combination of solar+wind+hydro. (hydro has its own issues, but a lot of capacity already exists, and it's great for levelling demand)

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