Potential for worldwide displacement of fossil-fuel...

[huon]

This post was published May 15, 2015 on Brave New Climate. Link here:
bravenewclimate.com/2015/05/15/potential-for-worldwide-displacement-of-fossil-fuel-electricity-by-nuclear-energy-in-three-decades-based-on-extrapolation-of-regional-deployment-data/

The paper by Qvist and Brook covered here was a forerunner of the excellent book A Bright Future by Goldstein and Qvist.

This BNC Discussion Forum thread is for the comments related to this BNC post.

[David B. Benson]

Just now there is not encouraging news.

The price of natural gas keeps dropping so many turn to that as the backup for wind, maybe also solar. Until the nuclear engineers can design a price competitive unit, gas will win.

[huon]

Yes, that's a challenge, DBB. A moderate carbon tax would certainly help.

According to a table in this article, a carbon tax of $20 (per metric ton of CO2) would raise the price of gasoline by 18 cents per gallon, and the price of natural gas by $1.06 per 1000 cu. ft. So if gasoline is selling for $3.00, $0.18 would add. about 6%, but for natural gas at $2.75, $1.06 would add nearly 39%.

If memory serves, the cost of combined-cycle electricity would rise about 1 cent per kWh, and that of open cycle almost two.

[David B. Benson]

StarCore Nuclear is advancing a 15 MWe HTGR through Canadian approvals, according to World Nuclear News. The size of this SMR is abound right to use as backup for wind power. I don't know if the other characteristics are suited for that role.

GFP, Global First Power, has a 5 MWe HTGR further along in Canadian approvals; same article.

[David B. Benson]

Alas, while pricing is goodnight for off grid localities, these are much more expensive than firing pipelined natural gas.

[huon]

Moltex Energy has designed a molten salt reactor with the fuel salts confined in tubes. To provide load-following reserve, some molten salt can be stored in tanks. The company anticipates the cost of this reserve electricity to be 38.21 Pounds (~$50) per megawatt hour, which is less than the cost of natural gas backup.
www.moltexenergy.com/learnmore/An_Introduction_Moltex_Energy_Technology_Portfolio.pdf (See Section 6.4 and Section 7)

[David B. Benson]

huon --- Could you explain more about this proposed molten salt store? I'm interested but not enough to attempt a pdf on this mobile device.

I assume that the proposed thermal store contains no actinides; that it operates to transfer heat solely via heat exchangers.

I suspect that they do not mention a maximum feasible size.

Thank you in advance, David

[huon]

Hi, DBB. Yes, no actinides in the thermal store. The Moltex website has a quick description of their reactor and the "GridReserve" option: www.moltexenergy.com/stablesaltreactors/

In the technical paper, Moltex has this to say about the reserve size: "GridReserve is envisaged to cater for several hour's generation from the SSR [Stable Salt Reactor]. For a 1GW plant, the storage will therefore be 1 GWh for each hour of storage capacity, enabling the plant to export double or triple capacity at times of peak demand/frequency response requirement."

I hope this information helps a little. Also, here is some reporting on Moltex by World Nuclear News:
www.world-nuclear-news.org/NN-Moltex-partners-in-New-Brunswick-SMR-project-1607185.html

[huon]

But back to the big picture. From the paper's abstract, quoted in the BNC post:

"Analysis of these regional deployments [by Sweden and France] show that if the world built nuclear power at no more than the per capita rate of these exemplar nations during their national expansion, then coal- and gas-fired electricity could be replaced worldwide in less than a decade. Under more conservative assumptions...our modelling estimates that the global share of fossil-fuel derived electricity could be replaced within 25-34 years. This would allow the world to meet the most stringent greenhouse-gas mitigation targets."

Prof. Brook concludes the BNC post:

"I think this is a genuinely exciting finding--yes we can!"

[Roger Clifton]

Decarbonising our electricity is one milestone, decarbonising our entire energy consumption is the main target. American per capita electricity consumption is 1.3 kW, but raw energy consumption is 9.2 kW (*).

If you consider that 1 kW of electricity requires about 3 kW of thermal energy then the "main target" would require about three times as much noncarbon power generation as the "milestone".

Nevertheless, the main target remains achievable. The energy revolution of Sweden and France was achieved with reactor designs that are now decades superseded. The rising sentiment for mass produced reactors provides the main hope for a mass rollout. Proof of that is only several years away, when the NuScale prototypes in Idaho begin to produce commercial electricity. Place your orders now!

Although its development is many years behind, synthetic fuel promises to deliver nuclear energy everywhere that powerlines cannot. Heating, trucking, shipping, aviation, agriculture and so on. So far, the antique Fischer-Tropsch synthesis is well-proven, but we need the chemists to bring us up-to-date news of more efficient processes.

(*) Source is World Bank after converting accountants' units to International Units.

[David B. Benson]

Roger Clifton --- So far Nuscale does not have a definite 2nd customer lined up.

[Roger Clifton]

So what? There is presently a world of interest watching the NuScale prototype plant go through its licensing. At some point, placing of orders will begin to accelerate and suddenly there will be a queue a mile long. Place your orders now!

[huon]

Romania, for example, just showed some interest in NuScale.
world-nuclear-news.org/Articles/Romania-to-explore-Nuscale-SMR-deployment

But, of course, much will depend on how the actual reactor performs.

[David B. Benson]

Also interest from Jordan and most important, Bruce Power in Ontario, Canada. Of course, Jordan is new to matters nuclear but has expressed interest to several potential vendors. Bruce Power, on the other hand, has 8 reactors. They need to replace 2 "soon" and need 2 more in addition.

[engineerpoet]

Mar 18, 2019 19:38:14 GMT 9.5 Roger Clifton said:

Decarbonising our electricity is one milestone, decarbonising our entire energy consumption is the main target.

This is a point that's lost on way too many "environmentalist" types.  They hype wind and PV, while ignoring not one but two elephants in the room:

1. Wind and PV are almost entirely confined to use for electric generation.
2. Other uses, such as transportation, space heat, industrial process heat and the chemical industry emit far more carbon than the electric generation sector; even if the latter was 100% decarbonized we would still have failed utterly.

American per capita electricity consumption is 1.3 kW, but raw energy consumption is 9.2 kW (*).

No need to make vague references; the EIA has it all right here. 101.268 quadrillion BTU/yr is about 3.385 TW or just over 10 kW/capita.

If you consider that 1 kW of electricity requires about 3 kW of thermal energy then the "main target" would require about three times as much noncarbon power generation as the "milestone".

That depends heavily on the technology; non-LWR reactors can get thermal efficiencies upwards of 40%.

Nevertheless, the main target remains achievable.

Indeed it does, and we have our choice of ways to get there.

If we had a government that was serious about dealing with the twin issues of climate change and energy security, we'd already have an effort at something like NRTS to build a zero-emission city.  The technology that's nearest to deployment right now is probably NuScale, so go with that.  The meltdown-proof nature of the NuScale reactor means that the emergency planning zone can (and should) be limited to the walls of the building.  Ergo, the reactor goes smack dab in the center of the development.

Electric power is decarbonized, of course.  Space heat and DHW is decarbonized by district heating with hot water heated in the turbine condensers (perhaps augmented with solar thermal panels to maximize electric generation for A/C in summer).  Transportation is mostly decarbonized with plug-in vehicles.  That leaves industrial process heat, which can also go electric if power is cheap enough.

I have not seen the full info on the uprate of the NuScale from 50 MW(e) to 60 MW(e), but I assume that it involves a thermal uprate from 160 MW(t) to 192-200 MW(t).  Assuming 10 kW(t)/capita one NuScale should be able to support ~20,000 people.  This is probably pessimistic because that would include a whopping 3 kW(e)/capita and something like 6 kW(t) of heat for space heat and DHW.  6 kW(t) is about 20,000 BTU/hr; multiply by 4 for a typical family and you have the rating of a decent-sized furnace.

If you really wanted to get clever, you'd have a dump load of some kind to turn excess electric power into storable energy.  The easiest of those is ice storage for A/C, but you'll also want chemical fuels for long-term storage and backup.  Ammonia is one such, but plasma gasification of solid waste and sewage sludge into syngas is the first step in making almost any desired liquid fuel.  That gets rid of 3 problems and turns them into 1 asset.  The only solid effluent is slag, which I understand is generally non-leachable and can be used in a host of ways.

Call it "Nukeville".  We could start building it in the Idaho desert today if we had a government with vision.  Unfortunately the visionaries who like nuclear think climate change is a commie plot, and the visionaries who think climate change must be dealt with generally think that nuclear energy is downright satanic and would rather follow floundering Germany than decarbonized France, Sweden and Ontario.  This is a recipe for failure, and we've been following it to the letter.

[engineerpoet]

Mar 8, 2019 11:10:18 GMT 9.5 huon said:

Moltex Energy has designed a molten salt reactor with the fuel salts confined in tubes. To provide load-following reserve, some molten salt can be stored in tanks.

I just went there to look.  They are proposing to use the same "solar salt" as Cal Abel and co-author did in their 2013 paper.

[Roger Clifton]

Mar 31, 2019 3:15:02 GMT 9.5 engineerpoet said:

Assuming 10 kW(t)/capita one NuScale should be able to support ~20,000 people.

... and their workplaces, including heavy industry, which sucks up a lot of power.

If you really wanted to get clever, you'd have a dump load of some kind to turn excess electric power into storable energy.

What to do with excess electrical power has long been an unsolved problem for the intermittent generators and remains so: any serious industrial process that could use large quantities of electric power when it is active, must pay interest on its capital whether it is active or idle. Nevertheless a system of tanks and pumps appears to have low enough capital to justify pump hydro as a means of storing electricity. But that's about it.

Storing excess thermal power would seem to be even worse proposition. However desalination by multistage flash distillation of water does involve a series of tanks with water at various temperatures. Vapour is pumped from each tank of higher temperature and condensed in a heat exchange with the next cooler tank. Perhaps the tanks of highest temperature could be boosted intermittently by steam bypassing the turbines. If all exhaust heat went into the tanks instead of a cooling tower, the variation between full generation and full dump would only be 2:3 or so.

Dumping all the exhaust heat into a desalination plant has the advantage that fresh water is not being consumed by evaporation in a cooling tower. Instead the heat returns to the atmosphere by radiation and convection from the pipe farm. Shedding a gigawatt of heat would require one square kilometre to face the sky if the rate is 1 kW per square metre, so a NuScale desal would require 20 hectares.

you'll also want chemical fuels for long-term storage and backup.

… and for aviation, shipping, trucking etc. The venerable Fisher-Tropsch synthesis of liquid fuels starts off with CO and H2. This feedstock is available with the simple water shift reaction from CO2 and H2. However chemically inclined readers might see a more direct pathway from CO2 to hydrocarbons, perhaps by electrolysis. Please tell us if so!

Replacement of crude oil with recycled CO2 might seem to be decades away. However modern fuel refineries are already using 20% of their incoming oil (of chemical energy ~5 GW) for power, lighting, pressure, heating and hydrogen production. All of that fossil fuel could be replaced right now by an on-site nuclear power station.

[Roger Clifton]

BTW - the "kilogram of oil equivalent" is not a vague unit, it was actually defined precisely as ten million calories. With this definition, the World Bank has used the long-obsolete centimetre-gram-second system of units, but I guess that upgrading to the modern standard International System of units must seem like a commie plot to people so conservative they consider that oil is a fundamental quantity. (Insert laughing emoji here)

Similarly, the "ton of TNT equivalent" is precisely defined as one billion calories. That converts to 4.18 GJ and a kiloton converts to 4.18 TJ. That's not really all that much energy and I wish journalists would stop using it as a measure of awesomeness. Surely "terajoules" is impressive enough!

[engineerpoet]

Mar 31, 2019 13:23:46 GMT 9.5 Roger Clifton said:

any serious industrial process that could use large quantities of electric power when it is active, must pay interest on its capital whether it is active or idle.

This is why low capital cost and/or operation at reduced capacity when surplus power is not available is an essential feature.  Obviously the latter requires some other supply of energy.

Storing excess thermal power would seem to be even worse proposition.

Depends how you do it.  Cal Abel is a fount of ideas along these lines, and one of the things he came up with is a steam compression system for LWRs which increases the temperature enough to make solar-salt storage usable; you take the LWR outlet steam, squeeze it hard enough and you get ~500 C temperatures.  This really only works for buffering daily and maybe weekly cycles, of course.  The reverse step generates steam at much greater than LWR temperatures so you'd want a topping-cycle turbine which exhausts at close to LWR steam conditions and feeds the nuclear plant main turbine.  You might be able to get a 3:1 or 4:1 turndown ratio that way without having to reduce the reactor output a single watt.  For buffering highly variable sources like wind and PV you might just have resistance heaters in your molten salt system; do that and you could have more than 100% of rated plant output going into storage, just the thing for California's daily PV peak.

But that's at the hot end of the system and distillation is at the other.  IIUC flash distillation of seawater runs into scaling problems well before you hit 100 C temperatures, so you're not going to take much of a hit on system output even if you take 100% of the remaining steam flow (after all the feedwater heaters) for the stills.  Calcium carbonate is a real headache, and I understand that bicarbonate starts breaking down into carbonate, CO2 and water at about 50 C.

[Roger Clifton]

Desalination by MSD achieves the purpose of providing an intermittent consumer of excess intermittent power. Being a series of low-pressure tanks and low-pressure pumps, it represents a minimum of capital being kept idle between surges of supply. Exhaust heat from a steam power station goes into the incoming non-freshwater and is moved as a vapour from tank to tank. Variations in the incoming heat can be stored as heated feedwater, while excess electricity is used as it becomes available to move or accelerate the vapour.

If the incoming water is from the nearby sea, most of the used heat would be taken away by the outgoing concentrated brine. Calcium carbonate scale is not a problem if temperatures and concentrations are kept low.

I see more of an attraction to inland cities, where fresh water is scarce and grey water needs recycling. Such places have become jealous of seeing their precious water disappearing as clouds leaving a cooling tower. Cooling towers are now better replaced by a source of freshwater.

[engineerpoet]

Apr 4, 2019 4:25:17 GMT 9.5 Roger Clifton said:

Desalination by MSD achieves the purpose of providing an intermittent consumer of intermittent excess power.

Not nearly as much as you think.  I ran some numbers and between condenser water out at 70 F and boiler feedwater in at 500 F and 700 psia, you've got the potential to take about 1/3 of the total enthalpy that's in the superheated steam being put out at 550 F and recycle it via feedwater heaters.  If you're tapping off barely-saturated steam at 140 F you've got at most 1/3 of your net energy remaining there (between energy extracted from the turbine and steam tapped to heat feedwater), so that's your maximum turndown ratio even if you can divert 100% of the 140 F steam.

The great thing about a steam-compression energy storage system is that it can both reduce net plant output by self-consumption of electric power for the compression system in addition to reduced turbine steam flow, and boost net output power by adding both additional generation and main-turbine steam flow when drawing down the heat store.  A ratio of 4:1 yields far more flexibility than 3:2.

Being a series of low-pressure tanks and low-pressure pumps, it represents a minimum of capital being kept idle between surges of supply.

I wouldn't underestimate the cost, especially O&M for stuff in a corrosive environment.

Variations in the incoming heat can be stored as heated feedwater

Low-grade heat is extremely expensive to store.

Calcium carbonate scale is not a problem if temperatures and concentrations are kept low.

Or if you just keep calcium and/or carbonate ions out of the system.  Using forward osmosis as the first step with e.g. pure NaCl solute as the carrier liquid does that; it gets rid of the need to treat the inlet water for anti-scaling purposes and probably anti-fouling also.

I see more of an attraction to inland cities, where fresh water is scarce and grey water needs recycling.

The city nearest to me apparently has to use reverse osmosis as the final polishing step before discharging its wastewater.  I'm not sure why, the newspaper fails to report details like that, but I suspect it has to do with nitrate and/or phosphate discharge limits.

Cooling towers are now better replaced by a source of freshwater.

You fail thermodynamics.  Large bodies of water are fairly efficient radiators of heat and lose a great deal less by evaporation than cooling towers do, but most power plants are sited on rivers which seldom have issues with insufficient water flow.  If you are willing to accept a hit to your thermal efficiency you can use dry cooling towers.

[huon]

Last weekend, Goldstein, Qvist and Pinker had an opinion piece in the New York Times:

"Nuclear Power Can Save the World"
www.nytimes.com/2019/04/06/opinion/sunday/climate-change-nuclear-power.html

Based on their excellent book A Bright Future, the authors' short essay is a gem.

[Roger Clifton]

The first point of the desal exercise is have the nuclear power station demonstrating its environmental credentials by generating potable water rather than consuming it. Worldwide, cities are running short of water supplies and are resorting to mining groundwater. Rather than adding to the problem by consuming water in highly visible cooling towers, a nuke can actually supply potable water to as many people as it supplies electricity. Now unpopular, cooling towers are better replaced by a source of freshwater.

A second value, in preferring evaporative desalination rather than the more fashionable reverse osmosis, is to provide an intermittent customer for intermittent power in a renewables-ridden grid. Exhaust heat from the power station provides the large quantities of latent heat needed for evaporative desalination. For a minority of the time, excess electricity on the grid now has a customer, to pump vapour between distillation tanks.

Apr 11, 2019 5:53:56 GMT 9.5 engineerpoet said:

If you're tapping off barely-saturated steam...

There is no need to tap off steam. The warming (not boiling) of the brine/grey water would be designed into the condensation stage of the power station.

Low-grade heat is extremely expensive to store.

Quite the opposite. We are not storing steam here. It is warmed water flowing into large tanks, which must be about the cheapest possible storage of heat.

Large bodies of water are fairly efficient radiators of heat

Near ambient temperatures, warm water loses its heat to the environment by evaporation rather than (net) radiation.

Most power plants are sited on rivers which seldom have issues with insufficient water flow.

Are you kidding? During high summer, thermal power plants are often shut down in North America and Europe to avoid overheating the rivers. Warmed water loses its oxygen, giving rise to extensive "fish kills". In Australia power is mainly generated on the coast, because even our biggest rivers often fail to reach the sea, although dry cooling towers are sometimes used inland. How much better would it be if local power plants continue to provide electricity during high summer, along with a copious flow of fresh water?

[engineerpoet]

May 12, 2019 19:34:44 GMT 9.5 Roger Clifton said:

There is no need to tap steam off.

You're always tapping steam off; that's part and parcel of the feedwater heaters.  (Speaking of which, I need to get back to my thermo analysis that I've been distracted away from.)  You're not going to be running a still on heat at condenser temperature because you don't have enough ΔT between the heat source and your ultimate heat sink.  You will instead be tapping steam off the turbines at somewhat greater than the temperature of your first distillation stage.  Instead of pushing turbine blades, that stream of heat powers the separation of fresh water from salt.  You're going to take a hit in turbine output when you do this.

We are not storing steam here.

You wrote "Variations in the incoming heat can be stored as heated feedwater".  You're talking flow rates on the order of the condenser coolant flow.  That's not going to be cheap.  It would be best just to size the still for the maximum thermal power.

Near ambient temperatures, warm water loses its heat to the environment by evaporation rather than (net) radiation.

Not true, and also highly dependent on ambient humidity.  Suez technologies says there is no significant loss.  This old study (well before the effort to demonize once-through cooling systems in order to shut down nuclear power plants) finds that evaporative losses in once-through systems are well below those of cooling towers or ponds.  Later results that I recall which showed that something like 70% of heat was given up as radiation are probably there but definitely buried under the hit pieces.

During high summer, thermal power plants are often shut down in North America and Europe to avoid overheating the rivers.

That's what auxiliary cooling towers are for.  Vermont Yankee had some; they are only needed when water temperatures are too high for condenser cooling water to be put directly back in the river.  They also do a really good job of oxygenating the water.

[Roger Clifton]

Perhaps I have not been clear. A multiple effect distillation plant takes water from a (possibly large) reservoir of warm water at ~70 C and atmospheric pressure. When electric power becomes available, the warm water is then fed through a series of closed tanks. The vapour at the top of one tank is then pumped into condensing pipes in the adjacent tank, so that the latent heat from the condensation is transferred to the next tank. The process is approximately isothermal, does not require a high temperature difference. If it is adjunct to a power station, heat flows into the reservoir/pond whenever the powerplant is running but the pumping can be run intermittently, when electricity is in low demand.

The power plant heat is lost from the desalination plant, from its outflows, and particularly from the large pond of warm water. Evaporation is the main cause of heat loss, not radiation. I recommend readers check out Figure 1 in this study. Radiation loss from the pond is less than the radiation gain from the sun and sky. In the absence of a desal process, it is the much greater evaporation that cools such ponds.

If we are to appease a fearful public, it would help to get rid of the nukes' cooling towers.  To the educated they are wasters of precious water.  To the uneducated, they have become threatening demigods on our skyline, imposed by an arrogant technocracy. Without cooling towers or smokestacks, a nuclear power station could instead become invisible and unthreatening as a clutter of industrial buildings in an industrial area.

[engineerpoet]

May 13, 2019 9:48:56 GMT 9.5 Roger Clifton said:

Perhaps I have not been clear. A multiple effect distillation plant takes water from a (possibly large) reservoir of warm water at ~70 C and atmospheric pressure. When electric power becomes available, the warm water is then fed through a series of closed tanks. The vapour at the top of one tank is then pumped into condensing pipes in the adjacent tank, so that the latent heat from the condensation is transferred to the next tank.

You appear to be confusing multiple-effect distillation with vapor-compression systems.  This video has a decent description of a multiple-effect still:  www.youtube.com/watch?v=kHMlLDsJqXE

If we are to appease a fearful public, it would help to get rid of the nukes' cooling towers.  To the educated they are wasters of precious water.  To the uneducated, they have become threatening demigods on our skyline, imposed by an arrogant technocracy. Without cooling towers or smokestacks, a nuclear power station could instead become invisible and unthreatening as a clutter of industrial buildings in an industrial area.

Appeasing unreasonable fears is how we've gotten nuclear into the mess it is in today.  Every new "safety" measure creates demands for "more safety", while coal fly ash, natural-gas explosions and air emissions from both of them kill more people every year than nuclear has since day 1.  Yes, including Hiroshima and Nagasaki!

Cooling towers are a perfectly reasonable way to discharge waste heat where large bodies of water are not available.  They're clean and quiet.  Educating the public about the facts is the ONLY ultimate solution; appeasing fears brainwashed into people by relentless and un-opposed propaganda is the road to ruin.

[huon]

In their book A Bright Future, Goldstein and Qvist have this to say about carbon taxes (pp. 200 -202):

"On the whole, carbon pricing has great potential to help slow climate change. It takes effect quickly and changes behavior across the whole economy without needing to tinker with each wind turbine or electric-car charging station in an effort to engineer similar outcomes. [...]

"Probably the main effects of carbon pricing will be not on individual energy conservation (turning down the thermostat) but rather on fuel choices at a larger scale. When an electric utility has to pay for carbon pollution from coal, and when nuclear power receives the same treatment as other low-carbon sources, then the economy can more effectively transition from fossil fuel to clean sources."

Advanced nuclear power and carbon taxes are synergistic, and we really need both to address climate change.


(Here is a 20 minute interview (podcast) with the authors, as well as a short article based on the interview.)
knowledge.wharton.upenn.edu/article/can-nuclear-energy-save-the-planet/

[David B. Benson]

China may be on track to meet its carbon emissions goals early
Leah Burrows
2019 Aug 14
Phys.org
m.phys.org/news/2019-08-china-track-carbon-emissions-goals.html

No. Just 50 cities does not a China make. Stll, some progress appears to be occurring.

[huon]

Climate change is scarier than nuclear power
Jack Edmonston
The Barnstable Patriot
Dec 28, 2019
www.barnstablepatriot.com/opinion/20191228/climate-change-is-scarier-than-nuclear-power

The views of Goldstein and Qvist, authors of A Bright Future, are featured in this insightful opinion piece. Pushker Kharecha, a member of James Hansen's team, is also quoted:

"'Our window of time to mitigate the climate crisis is shrinking by the day.... Given this urgency it simply makes no sense to curtail a non-fossil fuel source like nuclear power in countries that produce significant power from fossil fuels.'"

[huon]

Feb 21, 2019 11:57:32 GMT 9.5 huon said:

This post was published May 15, 2015 on Brave New Climate. Link here:
bravenewclimate.com/2015/05/15/potential-for-worldwide-displacement-of-fossil-fuel-electricity-by-nuclear-energy-in-three-decades-based-on-extrapolation-of-regional-deployment-data/

The paper by Qvist and Brook covered here was a forerunner of the excellent book A Bright Future by Goldstein and Qvist.

Now the influential US director Oliver Stone has a new film Nuclear: Time to Look Again based on A Bright Future. Given the renewed interest in nuclear power, the film comes at a good time indeed.