Significant Possibilities as DoE Explores Molten Salt Reactors--again

[samclem]

After a hiatus of 40 years, DOE is getting back into molten-salt reactor research, and thorium reactor research.

The DoE announcement yesterday indicated Oak Ridge National Lab (ORNL) will team with the Canadian firm Terrestrial Energy Inc. to assist with TEI’s new Integral Molten Salt Reactor (IMSR). Oak Ridge did research into similar designs in the late 1960s and early 1970s, but that work was defunded.

From Forbes:

Think of it: a nuclear reactor that:
- is cheaper than coal
- creates much less waste and few long-lived radioactive elements
- uses almost all of the fuel which lasts 7 years between replacement, and can be recycled easily
- is modular, from 80 MWt to 600 MWt, able to be combined and adapted to individual needs for both on and off-grid heat and power
- is small enough to allow fast and easy construction, and trucking to the site
- operates at normal pressures, removing those safety issues, and at higher temperatures making it more energetically efficient
- has the type of passive safety systems that make it walk-away safe
- does not need external water for cooling
- can load-follow rapidly to buffer the intermittency of renewables
- cannot be repurposed for military use and has strong proliferation resistance
- can last for many decades
- uses a liquid fuel
Now that is different!

The IMSR core-unit nested within a buffer salt liner. The unit is replaceable, after seven years just pop it out and replace it with another unit.

The liquid fuel has some advantages (ease of making it, ease of removing some troublesome elements). The design may be able to run on thorium instead of uranium, which has a lot of potential advantages.

The modular nature of the reactors and the easy scalability of the designs offer significant flexibility and cost savings (i.e. they can be built in factories and trucked to the sites, which is a LOT cheaper and more controllable than site-building the cores and other major components). The passive cooling and inherent walk-away safe nature of the designs will also be a big plus.

Still a long way from reality, and low oil prices could make it difficult to keep our resolve in funding this research, but it's a promising development.

 

[stepford]

Not the same technology, but this reminds me of the reactor across the street from the lab I worked at for 10 years. They had a little mishap a few years back (doubtless the source of my glowing personality...)

While I support new research into Fission (and Fusion) power, I must say that working in the midst of a massive environmental remediation effort following decades after a core meltdown puts the hazards into perspective.

 

[rbmrtn]

The molten salt concept has gotten a lot of interest lately

A link to their technology page Terrestrial Energy | IMSR Technology

Here's a white paper on a design concept ( another canadian company) http://transatomicpower.com/white_papers/TAP_White_Paper.pdf

Another good resource from the weinnberg foundation http://www.the-weinberg-foundation....-Molten-Salt-Reactors-Weinberg-Foundation.pdf

I think more interesting than thorium is that the design can use low enriched uranium, which essentially is the spent fuel that is currently in storage, so the existing spent fuel could be used provide fuel for the MSR.

Thorium itself is not fissile, so this is basically a breeder reactor. The thorium is transmuted into fissile material ( U233 ) which makes the reactor go.

 

[ERD50]

I think we really need something like this. Small, modular nuclear units just make so much more sense in so many ways. Distribute them to reduce losses in the grid, and improved redundancy.

As much as I'd like to see renewables gain in providing our power, they just are not practical at this point (and I'll wager not for another 20 years either) to provide significant % of our power. There are two large, recent Solar PV installations in our general area, 448KW each, each one covers the roof of a large school. I started watching their monitoring websites - well, much of our Dec was very overcast (not uncommon, but this was above norms), so very little power produced over a period of two weeks. I started looking again after the holidays, and was shocked to see almost no power being produced on a bright sunny day! I contacted some people at the schools and the monitoring site, I got responses (mostly - I dunno, I'll pass it on to someone), but the monitoring site admin mentioned that weather records show we had snow recently. Well, I knew that of course, and I looked over at the neighbor's roof, and yep - all covered with snow. So now these panels are producing near zero power for another solid week (so far). I never really noticed, but it seems we can have snow on our roofs for a long time. I wonder how much lost power this will be on average?

So for everyone who claims that solar is getting near cheap enough to compete with coal - you need to consider that it is very intermittent. It can't really compete w/o storage. And storage is not really practical, maybe possible if you have access to pumped hydro, and it has costs, and conversion losses. And can you imagine weeks of storage, followed by a few days of some sun, followed by another week of snow covered panels? That's a LOT of storage!


Without storage, the other option is to build an equal sized peaker plant, and feed it Nat Gas and run turbines when the Sun isn't shining or there is snow on the panels. So add the cost of a peaker plant to Solar PV - is it still 'cheap'? And how much fossil fuel was saved if the peakers are running through some of the day/night (depending on baseline power levels), and during overcast/snow days?

Unless something else comes along, I think these nuclear plants are our best option - we need reliable base line power.

-ERD50

 

[Texas Proud]

I think we really need something like this. Small, modular nuclear units just make so much more sense in so many ways. Distribute them to reduce losses in the grid, and improved redundancy.

As much as I'd like to see renewables gain in providing our power, they just are not practical at this point (and I'll wager not for another 20 years either) to provide significant % of our power. There are two large, recent Solar PV installations in our general area, 448KW each, each one covers the roof of a large school. I started watching their monitoring websites - well, much of our Dec was very overcast (not uncommon, but this was above norms), so very little power produced over a period of two weeks. I started looking again after the holidays, and was shocked to see almost no power being produced on a bright sunny day! I contacted some people at the schools and the monitoring site, I got responses (mostly - I dunno, I'll pass it on to someone), but the monitoring site admin mentioned that weather records show we had snow recently. Well, I knew that of course, and I looked over at the neighbor's roof, and yep - all covered with snow. So now these panels are producing near zero power for another solid week (so far). I never really noticed, but it seems we can have snow on our roofs for a long time. I wonder how much lost power this will be on average?

So for everyone who claims that solar is getting near cheap enough to compete with coal - you need to consider that it is very intermittent. It can't really compete w/o storage. And storage is not really practical, maybe possible if you have access to pumped hydro, and it has costs, and conversion losses. And can you imagine weeks of storage, followed by a few days of some sun, followed by another week of snow covered panels? That's a LOT of storage!


Without storage, the other option is to build an equal sized peaker plant, and feed it Nat Gas and run turbines when the Sun isn't shining or there is snow on the panels. So add the cost of a peaker plant to Solar PV - is it still 'cheap'? And how much fossil fuel was saved if the peakers are running through some of the day/night (depending on baseline power levels), and during overcast/snow days?

Unless something else comes along, I think these nuclear plants are our best option - we need reliable base line power.

-ERD50

I will take that wager.... but I am taking the over....

But, what do you consider significant (Also, need to throw out nat gas... for some reason they put that into the 'green' energy here)....

 

[ERD50]

I will take that wager.... but I am taking the over....

But, what do you consider significant (Also, need to throw out nat gas... for some reason they put that into the 'green' energy here)....

Oh I don't know - how about renewable (wind and/or solar) providing 25% of the average power in a couple dozen good sized metro areas as a fairly low bar?

There might be some cities in Europe/UK in that ballpark, but I think they either depend a lot on hydro (not available everywhere, and its 'greenness' is questionable), and/or relying on neighboring grids to draw from and/or dump excess. So that average depends on what you look at as a denominator.

If solar on average is providing its power for say 8 hours, that's 1/3rd of the day, so it would need to provide roughly 75% of the grid power during those 8 hours to average 25%. Some of that average could come from wind, but then again, these are all intermittent, so peaks will need to be higher to average out to even 25%. And (using admittedly very rough estimates), if the peaks are that much higher, some of the energy will go to waste if there is no storage. That's why even 25% is a pretty tough number IMO.


-ERD50

 

[samclem]

The present high availability and low prices of oil/gas are great, but they won't last forever. The liquid stuff will be needed for a >long< time for some applications (air transport, chemical production, maybe surface transport), so it makes sense to use this breathing spell and the relatively good economic conditions fostered by cheap oil/gas to do the research into this nuclear baseline power. And to the degree it can displace coal for electricty production and even process heat, that's great (CO2 aside, mining coal leaves a mess and burning it does pollute the air). If it makes electricity cheaper, that helps the plug-in EV case and >might< even reduce oil use.

The modular design of these plants (and some other fission reactor types) is key to keeping construction costs down and safety high (e.g. welds and other fabrication done in the controlled environment of a factory are much more easily done and inspected). Standardization across hundreds of cores and plants makes sure lessons learned at one can be directly applied elsewhere. This is an issue with our present nuclear plants: in many ways, each is unique and having scores of "pilot plants" ain't an optimum situation. This is one of those (rare) places where I see government involvement to enforce standardization (worked out with industry) to likely be required and beneficial (for public safety and, ultimately, the health of the industry). Any "savings" from doing things slightly differently at a plant are actually costs imposed on the public and on existing and future plants, and should be recognized as such and reduced as much as practical.

 

[Texas Proud]

Oh I don't know - how about renewable (wind and/or solar) providing 25% of the average power in a couple dozen good sized metro areas as a fairly low bar?

There might be some cities in Europe/UK in that ballpark, but I think they either depend a lot on hydro (not available everywhere, and its 'greenness' is questionable), and/or relying on neighboring grids to draw from and/or dump excess. So that average depends on what you look at as a denominator.

If solar on average is providing its power for say 8 hours, that's 1/3rd of the day, so it would need to provide roughly 75% of the grid power during those 8 hours to average 25%. Some of that average could come from wind, but then again, these are all intermittent, so peaks will need to be higher to average out to even 25%. And (using admittedly very rough estimates), if the peaks are that much higher, some of the energy will go to waste if there is no storage. That's why even 25% is a pretty tough number IMO.


-ERD50

I did not have hydro on my mind... when was the last big hydro plant built

But I will still take the over... I do not see wind/solar/wave/geothermal making up 25% of production in let's say 10 major cities in the US.... heck, I would be surprised if you even expanded it to the world (this excludes hydro)....


Edit to add.... I just looked at green providers for my area and they say that renewable energy production for Texas is 11%.... so I could be wrong... Hope the bet was not that big...

 

[ERD50]

....

Edit to add.... I just looked at green providers for my area and they say that renewable energy production for Texas is 11%.... so I could be wrong... Hope the bet was not that big...

Yes, but each additional percentage point becomes harder and harder.

At 11%, you are probably talking about mostly being able to wind down the peaker plants when the renewables are producing. No big changes to the grid, and the renewables save them the fuel costs of the peakers. Works fairly well.

But as you add renewables, you need to keep cutting back the big coal and nuke plants to let the renewables take that bigger portion. And the coal and nukes don't throttle up/down well. So what then? You need more peakers and they need to run more to fill in the gaps from the intermittent renewables. Peakers cost more to run than coal and nuke, offsetting the benefits of the added renewables. It's vicious.

-ERD50

 

[Texas Proud]

Yes, but each additional percentage point becomes harder and harder.

At 11%, you are probably talking about mostly being able to wind down the peaker plants when the renewables are producing. No big changes to the grid, and the renewables save them the fuel costs of the peakers. Works fairly well.

But as you add renewables, you need to keep cutting back the big coal and nuke plants to let the renewables take that bigger portion. And the coal and nukes don't throttle up/down well. So what then? You need more peakers and they need to run more to fill in the gaps from the intermittent renewables. Peakers cost more to run than coal and nuke, offsetting the benefits of the added renewables. It's vicious.

-ERD50

Also, one of the other things is that they say that the energy that is 'used' at your house might not be green at all... it is just that they will put that amt of electricity in the system somewhere....

There is a lot of wind mills out in West Texas.... pretty bad eyesore IMO... but there are not enough transmission lines to get it to East Texas... and remember that Texas is not connected to any other grid...


Here is what Texas has... so 50% coal and nuclear:

ERCOT Texas State Average Fuel Mix
State Average (2013)
Coal and lignite 39%
Natural gas 40%
Nuclear 10%
Renewable energy 11%
Other <1.0%
Total
100%

 

[ERD50]

Yes, but each additional percentage point becomes harder and harder.

At 11%, you are probably talking about mostly being able to wind down the peaker plants when the renewables are producing. No big changes to the grid, and the renewables save them the fuel costs of the peakers. Works fairly well.

But as you add renewables, you need to keep cutting back the big coal and nuke plants to let the renewables take that bigger portion. And the coal and nukes don't throttle up/down well. So what then? You need more peakers and they need to run more to fill in the gaps from the intermittent renewables. Peakers cost more to run than coal and nuke, offsetting the benefits of the added renewables. It's vicious.

-ERD50

A follow up to this post - I've seen some recent reports that Denmark is getting ~ 39% of their power from wind. Now that would seem to be very difficult based on what I said in my earlier posts. The following link says they actually got 100% from wind at one point. How to explain this?


Denmark surpasses 100 percent wind power – German Energy Transition


Ahhhh, it's all a matter of what you use for the denominator. Denmark is linked to the grids of Sweden, Norway and Germany. So when they have excess, it goes out of the country. And when they have a deficit, they import electricity. So is it really 'fair' to say that Denmark gets 39% of its power from wind? I think its more fair to include the grids in Norway and Germany and Sweden in the denominator, and then figure that % from wind.

So this illustrates my point - at 39%, they are very reliant on outside grids. Without that added source/sink, they would max out at a much lower % before they would need to shut down wind turbines to keep from over-driving the grid. So every added turbine past that point gets less and less utilization, so they need to charge more and more to cover their capital costs and ongoing maintenance.

So this would be like getting to the (hypothetical) point where Texas claimed it was producing 40% of its power from wind, but was reliant on neighboring states with no wind power (again, hypothetically) for source/sink of excess/deficit. We could not claim the US was at 40%.

-ERD50

 

[meierlde]

A follow up to this post - I've seen some recent reports that Denmark is getting ~ 39% of their power from wind. Now that would seem to be very difficult based on what I said in my earlier posts. The following link says they actually got 100% from wind at one point. How to explain this?


Denmark surpasses 100 percent wind power – German Energy Transition


Ahhhh, it's all a matter of what you use for the denominator. Denmark is linked to the grids of Sweden, Norway and Germany. So when they have excess, it goes out of the country. And when they have a deficit, they import electricity. So is it really 'fair' to say that Denmark gets 39% of its power from wind? I think its more fair to include the grids in Norway and Germany and Sweden in the denominator, and then figure that % from wind.

So this illustrates my point - at 39%, they are very reliant on outside grids. Without that added source/sink, they would max out at a much lower % before they would need to shut down wind turbines to keep from over-driving the grid. So every added turbine past that point gets less and less utilization, so they need to charge more and more to cover their capital costs and ongoing maintenance.

So this would be like getting to the (hypothetical) point where Texas claimed it was producing 40% of its power from wind, but was reliant on neighboring states with no wind power (again, hypothetically) for source/sink of excess/deficit. We could not claim the US was at 40%.

-ERD50

If you monitor the ERCOT site you find that wind power varies greatly, at times up to 30% now that the transmission system has been upgraded, since the turbines are not where the grid ran in the past. With this upgrade wind curtailments on the ercot grid have nearly disappeared compared with before the completion of the transmission upgrades. (note that the percentage also varies with the load). Tx is at roughly 11 GW of wind turbines on the grid.

 

[meierlde]

Also, one of the other things is that they say that the energy that is 'used' at your house might not be green at all... it is just that they will put that amt of electricity in the system somewhere....

There is a lot of wind mills out in West Texas.... pretty bad eyesore IMO... but there are not enough transmission lines to get it to East Texas... and remember that Texas is not connected to any other grid...


Here is what Texas has... so 50% coal and nuclear:

ERCOT Texas State Average Fuel Mix
State Average (2013)
Coal and lignite 39%
Natural gas 40%
Nuclear 10%
Renewable energy 11%
Other <1.0%
Total
100%

Out around Sweetwater what scenery is spoiled non in fact the turbines provide some more variety in scenery. So the issue of eyesore is in the eye of the beholder.

 

[ERD50]

If you monitor the ERCOT site you find that wind power varies greatly, at times up to 30% now that the transmission system has been upgraded, since the turbines are not where the grid ran in the past. With this upgrade wind curtailments on the ercot grid have nearly disappeared compared with before the completion of the transmission upgrades. (note that the percentage also varies with the load). Tx is at roughly 11 GW of wind turbines on the grid.

Am I misreading the site stats?

Energinet

Right now (around midnight there, which I would expect to be lower consumption and higher wind), it shows a lot of exports.

1405 > Jutland NO
351 > Jutland SW
903 > Zealand SW
14 > Bornholm SW

And imports:

860 + 590 from Germany

says net 1234 export, 3314 consumption... does that add up,( yes close net 1223 - it is in real time, so some numbers changed a bit as I entered them)?

Wind producing 3135; 980 + 433 from power plants. OK, that adds up (total power minus consumption minus net exports near zero).

So something like 40% of their wind right now would need to be shut down (not earning $) if they couldn't export it. It might be worse, since from what I read, that import from Germany is also wind, but Denmark has the grid connections to absorb their excess and pass it on to Norway and Sweden. I'm guessing this is fairly typical through the night?

They may not be curtailing (shutting down) the turbines, but they do seem to depend on the external grids for sink/source. This is why I say it isn't apples-apples to a comparison of where the US could go with wind %, w/o some not-yet-available-storage-system.

-ERD50

 

[Chuckanut]

Ahhhh, it's all a matter of what you use for the denominator. Denmark is linked to the grids of Sweden, Norway and Germany.

Like my old grand pappy used to say. "Figures don't lie, but liars sure figure."