Nuclear vs wind+solar+storage American edition 1

[JoshPlumSE]

Tug -

Yeah, I don't know how the solar / wind stuff relates to this thread much. Certainly, not much related to nuclear. The only real energy in nuclear is by super heating to produce steam and power the turbines to create energy. Maybe there is a way to capture some of that start up (or cool down) energy as well. But, I'd have to think that it's a relatively minor consideration.

The only article I remember seeing about storing solar heat energy was also a Bill Gates backed project, but one that involved only Solar. I think this might have been the article below.

https://www.cnn.com/2021/03/24/business/heliogen-solar-bill-gates-rio-tinto/index.html

 

[btrueblood]

Tug, yes there is wind and solar that goes unabsorbed by the grid. Due to changes to Federal law, mandating minimum flow thru the Columbia River dams for fish passage (flushing baby salmon downstream), they often have to demand that the wind farms along the Columbia and Willamette river valleys shut down production in the springtime.

edit: read the stuff on the TerraPower website - the idea is to be able to store wind and solar power for peaking, leaving the nuke to satisfy base load. The salt battery is simple tech that can store a heckuvalot of energy far cheaper than batteries.

 

[TugboatEng]

The only places that can experience excess power from renewables are essentially islanded. Instead of investing in storage I think we would invest in interconnectivity so that we can maximize consumption of renewables and forget about storage.

I think the goal is to take smaller grids and score some 100% renewable nights with storage and low demand to create cases that can be used to say, we told you so. It's not going to provide any real benefit but it will be used to sway politicians.

 

[GregLocock]

If you can describe the whole of Australia as an island, then yes we do curtail wind and solar at times. More frequently we have a negative price for wholesale electricity, which is one of the things that kills the economics of baseload generators.

Cheers

Greg Locock


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[JoshPlumSE]

I think the goal is to take smaller grids and score some 100% renewable nights with storage and low demand to create cases that can be used to say, we told you so. It's not going to provide any real benefit but it will be used to sway politicians.

Yeah, I think that is one of the goals. Smaller power plants close to the demand. I did a project (actually a few) for a company called Fuel Cell Energy. It's a pretty green form of power, but not all that scalable. Their chief product was a small 250 kW fuel cell power plant that could be installed for a site. Often it was an industrial site of some kind, or a hospital. Any facility where it was necessary to be able to run "off grid" in the case of power outages and such.

I think it's a good idea. As our government moves away from fossil fuels and makes electricity production more and more expensive, there is something VERY attractive about being more independent and not having to rely on the constantly changing regulatory and political climate.

 

[btrueblood]

"The only places that can experience excess power from renewables are essentially islanded. "

Hunh?

Islanded, Tug? What part of the PNW grid is an island, when a large portion of our grid supplies California's power demand?

 

[btrueblood]

The point is, you have free energy from solar/wind, that may or may not, in a given moment, have a user. Sure, shut down the wind turbine (feather the blades), or shroud the solar cells (or just turn off the switch to the charger?), but the point is there is an opportunity for the owner of the solar cells and wind turbines to generate electricity, but they have no market to do so. So, store it and then sell it later, regardless of how leaky your storage bucket is - the energy is free (and you have already paid the sunk cost of building the turbines and solar cells). You make some money, which is better than no money.

 

[JoshPlumSE]

btrueblood -

I took the "islands" comment about renewables to mean that they are only feasible in relative small, isolated areas. That's true for ALL power since the further you send it, the more transmission loss you get. Say for example:
a) Wind Farms over in Palm Springs: These are only feasible in places where the wind blows relatively hard and consistently. And, where land is relatively cheap. There are far, far more locations that cannot benefit from wind power than there are locations that will benefit.

b) Take a look at the Ivanpah solar plant off of Interstate 15 on the way to Vegas: This type of solar plant takes an incredible amount of land relative to other types of power plants. It's only feasible in places that get a lot of sun, few clouds and where the land is really cheap.

c) Take a look at geo-thermal power like they use in Iceland. That's great, but there aren't very many places that have very stable geo-thermal sources like that. Maybe we could do that in Yellowstone National park with all the geysers. It might be possible (probably not) in some places in Hawaii. Regardless, these types of places are very, very rare.

I should also point out that these locations are very often locations where not a lot of people live. Who wants to live where the wind is blowing all the time? With solar, the need for cheap land inherently means that there is usually a good amount of distance between the power plant and the population centers. Desert areas of CA, NV and AZ are probably the best places in the US for this. You could see the Middle East and Africa doing something like this..... Except the Middle East has so much oil, they don't see the need. Probably relatively few African nations would be willing to pay the relatively high cost of this power (when compared with conventional fossil fuels).

 

[btrueblood]

Well, again, I disagree - the whole point of this thread is to find (or at least estimate the requirements of) a renewable power grid scheme, which implies having some factor greater than 1 for renewable power production (more probably 3x to 4x) and then some means of storing the renewable energy to make up for when the sun don't shine and the wind don't blow (or the rains don't come). Power transmission losses are small potatoes versus conversion losses from whatever storage mechanism you invoke. And then you start to look at nuke plants for baseload, because they work.

 

[JoshPlumSE]

I'm just explaining what I took that "islands" term to mean.

The larger point about "islands" where it can work. If you find some "Islands" in the CA, NV, and AZ desert, then you've still made major improvements. It doesn't matter that this technique doesn't work EVERYWHERE.

We can put nuclear just about anywhere that has a sufficient water supply to prevent a meltdown, of course. So, this will be a big improvement as well if we actually do it. I think we've got Hydro power already in most places where it's feasible. But, maybe there are more places in the other mountainous areas of the US that would benefit as well.

Power transmission losses are small potatoes versus conversion losses from whatever storage mechanism you invoke

That's probably true. But, I'm operating off the assumption that these plants are already about as efficient (in terms of converting energy into electricity) as they're going to be. Perhaps the bigger problem with locating these power plants relatively far away from population centers is the INFRASTRUCTURE required to transmit the power. I think I read somewhere that some power company took over an abandoned Coal or nuclear power plant and turned it into some kind of solar plant. They chose the location specifically because it meant that they'd say a ton of money because the power lines, transformers and such were already there and basically hooked up to the grid.

 

[btrueblood]

Fair enough.

The coal plant being utilized (that I know of, there may be more) is the TerraPower project in Wyoming, it's being built on the site of a coal plant (coal plant was situated near a big coal strip mine, to reduce transportation cost of the fuel).

My understanding of some of the sodium metal cooled reactors is that they are built to be invulnerable to meltdown, i.e. passive cooling works to keep the core intact.

 

[JoshPlumSE]

Just to finish off the islands comment (since I had some dumba$$ typos in that post). Even if the islands of Solar, or wind or hydro don't work EVERYWHERE, you can still interconnect them.

Do this with a bunch of islands of "green" power, connect them with expanded nuclear, and whatever most efficient fossil fuel power we may still need for grid flexibility or base load..... Do this and we would have incredibly reduced CO2 emission for our power grid and for our nation in general.

That's sort of been my point all along. The energy economics side of it. I want the AGW alarmists to admit that we cannot get rid of fossil fuels completely in any foreseeable time frame. And, to stop pretending that Nuclear isn't green. It's incredible safe and reliable and has relatively little waste. Then add in as much "renewable" or "green" energy as we can at a reasonable cost.

This is the true path forward. Not the all or nothing Net Zero attitude that is doomed to fail.

 

[dik]

The articles I've seen stipulate it is a liquid fluoride salt, not liquid sodium.

From Wiki...

"The liquid fluoride thorium reactor (LFTR; often pronounced lifter) is a type of molten salt reactor. LFTRs use the thorium fuel cycle with a fluoride-based molten (liquid) salt for fuel. In a typical design, the liquid is pumped between a critical core and an external heat exchanger where the heat is transferred to a nonradioactive secondary salt. The secondary salt then transfers its heat to a steam turbine or closed-cycle gas turbine.[1]

Molten-salt-fueled reactors (MSRs) supply the nuclear fuel mixed into a molten salt. They should not be confused with designs that use a molten salt for cooling only (fluoride high-temperature reactors) and still have a solid fuel.[2] Molten salt reactors, as a class, include both burners and breeders in fast or thermal spectra, using fluoride or chloride salt-based fuels and a range of fissile or fertile consumables. LFTRs are defined by the use of fluoride fuel salts and the breeding of thorium into uranium-233 in the thermal neutron spectrum.

The LFTR concept was first investigated at the Oak Ridge National Laboratory Molten-Salt Reactor Experiment in the 1960s, though the MSRE did not use thorium. The LFTR has recently been the subject of a renewed interest worldwide.[3] Japan, China, the UK and private US, Czech, Canadian[4] and Australian companies have expressed the intent to develop, and commercialize the technology.

LFTRs differ from other power reactors in almost every aspect: they use thorium that is turned into uranium, instead of using uranium directly; they are refueled by pumping without shutdown.[5] Their liquid salt coolant allows higher operating temperature and much lower pressure in the primary cooling loop. These distinctive characteristics give rise to many potential advantages, as well as design challenges."

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[dik]

The liquid salt reactors don't require water or high pressures.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[btrueblood]

Josh,

My issue with the term "island" is that it is usually used (in the power biz) to describe a grid that is not interconnected to other grids, i.e. like the Hawaii power grid, or Western Australia versus the rest of Aus, or Texas vs. the rest of the free world, etc. You could maybe coin another term to talk about what you describe as an "island" - perhaps a self-contained multi-source power plant (SCoMPP? SCaMPP?)? Dunno, I stopped being an acronym guy when I left the aero biz.)

The rest of your post I 100% agree with.

Dik, no - please read deeper, both will be used. The REACTOR (nuke) core is cooled by liquid sodium metal, not a salt. The THERMAL STORAGE is a liquid (molten) salt. The plant will have both systems operating on a normal basis. The molten sodium is pumped to a heat exchanger (to heat the molten salt) and/or boiler (to generate steam for electric power generation via a steam turbine). Molten salt is also generated and stored by renewables (wind, solar, squirrel treadmills, whatever) when no grid sink for those is available. Molten salt can be pumped through the boiler as well, and power generated from the steam, for some duration depending, in part, on the output power level.

 

[dik]

None of the articles I've read make any reference to liquid sodium.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[btrueblood]

On the TerraPower website,

https://terrapower.com/natrium/

scroll down a bit (you may have to give an email address to view) to the heading "THE ADVANTAGES OF NATRIUM REACTORS OVER TRADITIONAL DESIGNS":

Natrium reactors are not pressurized like existing plants and use sodium, instead of water, as a coolant. The reactor operates at a temperatures greater than 350 degrees Celsius (the equivalent of 662 degrees Fahrenheit) and far below the boiling point of sodium.

Not molten salt, but liquid metal sodium. There are molten salt power reactors in development, or theorized (some proposed Thorium reactors and breeder type reactors) where the fuel itself is a molten liquid, but not this one. Example -

https://en.wikipedia.org/wiki/Molten-Salt_Reactor_Experiment

edit to add:

Additionally, it's unique design allows for separation and “decoupling” of the energy and nuclear island, ensuring the integrated energy storage and power production systems are completely separated from the nuclear portion of the plant.

This design permits non-nuclear project teams to operate significant plant operations like the steam turbines and salt tanks outside of the nuclear control area. This is safer and reduces costs.

Few reactor designs directly couple the reactor coolant loop to the power production loop, to avoid carrying radioactivity outside the reactor containment vessel. Sodium coolant becomes short-term radioactive when cycled through the nuclear core, but (I think) this is mostly alpha radiation which is shielded by the metal of the heat exchanger/boiler tubing.

 

[dik]

The liquid salt reactor was actually initially developed by the US and after careful consideration was scrapped for their normal reactor.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[stevenal]

Sodium (liquid metal) cooled reactors are not new. I worked at Fermi I the summer of '75 during the decommissioning. The coolant had been put into barrels and sealed while it was still too hot. The gaskets melted and some of the sodium leaked and reacted with the air. My job was to remove and clean the bung threads, and re-install the bungs with new gaskets. I cleaned the bungs with water in a sink. Every once in a while I'd get a tiny bit of un-reacted sodium that would spark and zip around in the water. This was not salt, salt simply mixes with water. Sodium metal reacts more violently. I wore safety glasses, and made sure the bungs were dry before re-installing them. I also wore a dosimeter and film clip.

 

[GregLocock]

Finally some commonsense from the US governement. I'll wait for you to recover, then read this. Including nuclear would reduce the cost of energy of wind+solar+battery power by 37%

https://liftoff.energy.gov/advanced-nuclear/

Cheers

Greg Locock


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