No it isn't. Ramping is slow and can't be done beyond 20% very often or you destroy your fuel and control rods
Reducing output doesn't reduce costs, it increases them. This is the opposite of dispatchable.
If you can only pay for your reactor by coercing people into buying daytime electricity for 20c/kWh rather than buying a solar panel that will pay for itself in 3 years then it's not dispatchable.
You don't need to alter the thermal output of the reactor to modulate a nuclear plant's electrical output. You can more aggressively cool the reactor to reduce the energy delivered to the turbine. This isn't often done since it's essentially deliberately reducing the efficiency of the plant.
> Ramping is slow and can't be done beyond 20% very often or you destroy your fuel and control rods
It's not slow: the turbine water is can be cooled more aggressively immediately, and will start reducing output with one circuit of the generation turbine. Also, modulation only needs to vary 20-30% over the span of entire days not of tens of seconds. And no, dispatchable generation does not ramp in 10s of seconds. Natural gas plants - the most popular peaking generation plant - still takes an hour to activate. But this isn't an issue because electricity use doesn't fluctuate by 20% in the matter of tens of seconds.
> And it's still not dispatchable if not using it costs you anyway.
No? This just plain wrong. A dispatchable source is a dispatchable source, regardless of any associated costs. And with nuclear there isn't even any direct cost with running the plant at a reduced capacity. There's only the opportunity cost of lost electricity sales, which would happen anyway because there isn't enough demand.
If there's 100 GW of peak demand and 80 GW of minimum demand, building 100 GW of nuclear plants and reducing output during periods of non-consumption does not have any increase of costs.
If there's noone to sell your $150/MWh electricity to because they took one look at the price and put a solar panel on their roof, then you're not selling $150/MWh electricity, you're selling $500/MWh electricity for the 20% of power they must buy. Then when they take a look at the new price, they go buy a battery. The only way to pay it off is a government enforced utility connection fee for a product nobody wants.
The only way to sell it for $150/MWh is to underprovision or to build storage or to find dispatchable loads. Just like renewables.
None of this has anything to do with dispatchablity. Nuclear power is indeed dispatchable, which is why you're pivoting to this strawman about pricing. If we had a primarily nuclear grid, there's be no need for solar panels anyway.
> Then when they take a look at the new price, they go buy a battery
You're making the same error a lot of renewable activists do: assuming that household electricity use is all there is. How do you power the turbopumps that make our sewage and plumbing systems? How about our telecommunications systems? We'll just deal with cell phones shutting off after dark?
Energy storage requirements are staggering. The world uses 60,000 GWh of electricity every day. Storage requirements are at least 12 hours for diurnal storage, and several days for seasonal storage. Just going out and buying a hundred terawatt hours worth of batteries is a lot easier said than done.
The mines and aluminium smelters and arc furnaces and polysilicon plants are all building their own renewables. They're not going to buy your daytime energy either when they can make their own DC power at $10-30/MWh. The industries which require hydrogen or derivatives will just make it on site and store a few weeks worth. The industries that need heat or steam will store it in a lump of iron ore wrapped in some fire bricks and rockwool.
Then you might want to just stop and think about how you might go about storing energy if you have a pump and a reservoir on a hill or a water tower. Just ponder that one for a few seconds.
> They're not going to buy your daytime energy either when they can make their own DC power at $10-30/MW
Unless it's night time. Or cloudy. Or during the winter when the incidence of the sun reduces solar output. Again, this is why any plan that involves cutting power to mines, smelters, etc. needs to factor in the costs of shutting down these industries when renewables fail to produce energy.
> Then you might want to just stop and think about how you might go about storing energy if you have a pump and a reservoir on a hill or a water tower. Just ponder that one for a few seconds.
Right, except we just have to have a lake on a hill handy. Some places have it. Most do not.
Why don't we just use hydroelectricity for all of our power needs? Ditch nuclear, and ditch solar and wind. Just build dams. Problem solved.
> Unless it's night time. Or cloudy. Or during the winter when the incidence of the sun reduces solar output. Again, this is why any plan that involves cutting power to mines, smelters, etc. needs to factor in the costs of shutting down these industries when renewables fail to produce energy.
So they'll buy your night time energy for the few hours a day when the wind farm they contracted with for less than your O&M costs isn't producing. Still doesn't help the nuclear operator pay the bills for the other 22 hours. Unless you're suggesting we ban people from supplying their own energy or making contracts with fully privately funded wind generators? Sounds pretty un-free to me.
> Why don't we just use hydroelectricity for all of our power needs? Ditch nuclear, and ditch solar and wind. Just build dams. Problem solved
You cited a need to store energy for moving water from a reservoir to where it is needed. Storing the amount of water you need to store but raise it up a little bit is a fairly well understood problem.
> Blocking water with a dam is a well understood problem
I feel like we still have some problems with dam building, because they keep failing. We struggle to get the building material (in particular, sand). Concrete is pretty awful in terms of CO2. Dams of all sizes cause problematic changes to the rivers they're on, and block flows of fish and other animals. Smaller low head weirs and dams kill humans.
Lots of time, money, and effort is going into removing smaller dams and low head weirs.
We won't need any storage. We'll just get all of our electricity from dams. Since it's a well understood problem we can build them anywhere we want in any quantity.
Nah, wind and solar are cheaper and safer and don't take as long. We can use the existing dams for dispatchable power though. As well as CSP of which the unsubsidized LCOE has recently hit parity with O&M of nuclear and is plummeting. Throw in some thermal storage as well, that's safe.
This is quite the tantrum to be having in response to being told that you don't need a nuclear reactor to pump water downhill. Was it really so earth shattering to your world view?
But you do need an alpine lake, with another body of water down below it to collect that water so it can be pumped back into the upper reservoir. The geography needed to built pumped storage is very specific. Simply saying that we can just build dozens of terawatt hours of pumped hydro is as nonsensical as saying we can just build more dams. Is that really so earth shattering to your world view?
You claimed that chemical storage is always necessary to pump municipal fresh water with VRE. I pointed out that this a perfect example of a dispatchable load because it is frequently already done with reservoirs and water towers and you had a tantrum and tried to straw man that as claiming all generation be backed by PHES.
And you need a reservoir down below to receive the water as it passes through turbines otherwise you're waiting for rainfall to fill that upper reservoir up naturally.
The geographic conditions to make pumped hydro are far more constrained than you seem to think. Most water reservoirs for municipal water supplies don't have the elevation drop to be used for generation and they don't have the lower reservoir to capture and feed water back into the upper reservoir.
By some bizarre coincidence they hold exactly enough energy to move the water down the hill to its destination at the pressure specified whenthe tower was built. So weird how that happens. Almost as if heating and transporting water have been trivially dispatchable loads for centuries before electricity was used to do them at all.
"The mines and aluminium smelters and arc furnaces and polysilicon plants are all building their own renewables."
They most definitely are NOT. Microsoft is building a gas turbine to power a data center in Ireland though, because data centers NEED POWER AT ALL TIMES!
Well done. Great comparison. An industry that needs five nines of uptime on their power supply in a country with worse solar resource than much of the arctic is totally representative of an industry which only needs to keep interruptions below 4 hours, has costs dominated by electricity and is adding it to reduce the bills.
And countless others so frequent they don't make the news. It's an absolute no brainer because solar is about the same price at any scale but fossil fuel micro generation is really expensive.
Reducing output doesn't reduce costs, it increases them. This is the opposite of dispatchable.
If you can only pay for your reactor by coercing people into buying daytime electricity for 20c/kWh rather than buying a solar panel that will pay for itself in 3 years then it's not dispatchable.