PowerGen pros and cons - an honest discussion

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Great post. Your typically awesome utility scale enlightenment Overkill.

Although pro nuke myself, there have been occasional catastrophes.

Chernobyl, fukushima, and a slew of smaller ones.

To your mind is this all design and human based , and totally preventable, or are there likely to be another or more like these?
 
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Run-of-river is less disruptive, but all hydro is going to have some impact on water flows and the life that exists within them.

Here's a local run-of-river dam, it's the one that I noted was ~150 years old, it's the London St. Generating Station which has a 10MW nameplate capacity:
View attachment 46106
Going by the above orientation:
- Bypass is on the bottom (flow through, there's your "minimal impact on fish")
- Turbines are in the centre
- Control dam (water height/flow) on the top

Thanks for that. Way back when we vacationed in Oregon where power was generated by a hydro turbine fed by a pipeline that originated on a large creek. The pipe was underground so the only thing you could see was the intake and then the turbine house. It was fascinating for us 50 years ago as the engineer who lived there gave a a complete tour. I’m not sure how many homes it powered. That area was mostly ranches and cabins.

There is a big push in the Pacific Northwest to get rid of the dams. The people on that side of the argument seem to not care about the flood control and the irrigation those projects gave us and the benefits of those projects. Agriculture is obviously a huge benefactor.
 

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Great post. Your typically awesome utility scale enlightenment Overkill.

Although pro nuke myself, there have been occasional catastrophes.

Chernobyl, fukushima, and a slew of smaller ones.

To your mind is this all design and human based , and totally preventable, or are there likely to be another or more like these?
I guess it depends.

Chernobyl was clearly the combination of operator error and a lack of containment, which was due to trying to keep costs down. Even after the meltdown, the plant continued to operate the remaining units up until the early 2000's after containment was added. There are still operational RBMK's around if you were not aware, which is somewhat surprising. With secondary containment, the event would have been far less catastrophic, but still devastating for those who struggled to contain it; it would have had no impact on that aspect of how that played out.

Fukushima was utility arrogance, having been implored by the Nuclear Safety Commission, but isolated from required action through grandfathering of old designs, to increase the height of the sea wall to what was considered the modern standard and relocate the emergency generators from sea level below the facility to behind it and above. TEPCO did neither and so the sea wall was breached, the generators flooded; their fuel tanks washed away and they couldn't cool the plant.

There are other designs that can be passively cooled however, that even if the situation had played out as it did, wouldn't have melted down.

I worry that China might cut a corner or 5 on one of their builds and have a "situation", but that concern may be misplaced. Modern safety standards, particularly post-Fukushima have really worked to improve facility hardening against LOC's.
 

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Thanks for that. Way back when we vacationed in Oregon where power was generated by a hydro turbine fed by a pipeline that originated on a large creek. The pipe was underground so the only thing you could see was the intake and then the turbine house. It was fascinating for us 50 years ago as the engineer who lived there gave a a complete tour. I’m not sure how many homes it powered. That area was mostly ranches and cabins.

There is a big push in the Pacific Northwest to get rid of the dams. The people on that side of the argument seem to not care about the flood control and the irrigation those projects gave us and the benefits of those projects. Agriculture is obviously a huge benefactor.
There were several pipe projects at Niagara Falls, though comparatively huge to the facility you mentioned. The Beck plants are both fed by huge tunnels from above the falls that run underneath the city of Niagara falls and I believe Moses is also tunnel-fed in a similar manner. I posted some pictures of one of the no longer operational tunnel heads and its facility below the falls in one of the picture threads recently, let me know if you missed it and I'll link you.

Yes, typically those advocating for the dismantling of the dams have little to no knowledge as to the impacts of doing so. Water flows and flooding have been controlled through these and removing them can have huge, and far-reaching impacts downstream.
 
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While the nuclear powering of Navy vessels, both carriers, and the different classes of submarines, does not have anything to do with supplying power to any grid, I still recall back in December of 2000 when I was in California to have my back worked on, I had a conversation with a retired alpha sub navigator, and I told him that one of my big concerns with nuclear is what could happen if a tsunami hit a costal region that had a nuclear reactor. And that I was both concerned about commercial reactors, and those on Navy vessels that were in port. He did not think the Navy vessels were anything to worry about and said that he considers the nuclear propulsion systems to be black boxes that are designed well and not part of anything he had to get involved with. My point is that if a reactor on a carrier or a sub were still hot enough from recent running to be requiring a flow of sea water to keep it properly cooled, and that vessel were to be picked up and carried ashore and set down and then the water drained away, it may be that they find themselves with an uncontrollably meltdown. To that extent I think it should be mandated that before any such vessel reach ports or for that matter shores where a tsunami could possibly leave it tossed onto dry land, the reactor(s) be cool enough to not require any cooling from sea water. And this requirement may not be necessary at some island ports if the combination of the layout of the port, the island, and the ocean including seismic activity sites meant that there was really no chance of that problem happening at that location.

I know that just the idea that something could be powerful enough to carry a vessel that large inland is almost outrageous, but the way big ships were tossed around in the Japan tsunami shows that it is not impossible.

I know the Navy is meticulous when it comes to nuclear power safety, but I still have to wonder if a tsunami is something that could cause a serious problem with a nuclear powered vessel that was in port or near shore when it hit.

I know it sounds far fetched and like a one in a million chance, or maybe it is more like 1 in 10 trillion, but it is not zero. Heck, just the possibility of a tsunami is a very very low chance. But back in 2000 I was also concerned about the possible effects of a tsunami effecting commercial units and that was before the Fukushima Daiichi disaster.

One of the things that stays in my mind is a history channel show I once saw about how far inland and at what elevation, evidence of a tsunami wave exists in a few places on the U.S. west coast. While I do not recall the specific data, the distance and height was way beyond what most people would expect.
 
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While the nuclear powering of Navy vessels, both carriers, and the different classes of submarines, does not have anything to do with supplying power to any grid,
Don't know if you noticed my mention of the Russian SMR's earlier, but that's exactly what they are, naval propulsion units slightly tweaked for providing shore power. There are two of them operating in Siberia on a barge right now and they have others under construction currently that are going to be deployed on land. Definitely the quickest and most cost-effective way to get an SMR.

On the ships and subs I'd assume that external water (sea water) is on the 2nd or even 3rd loop of the unit. These are also not very high thermal capacity when compared to a stationary unit so the cooling requirements would be massively smaller, particularly when shutdown. There may be enough thermal capacity within the internal loops to keep the units cool without any seawater in the shutdown state actually. I know a CANDU unit, which is HUGE in comparison, can convection cool using the flooded steam generators when in a shutdown state.

I can ask a twitter acquaintance of mine if you'd like a real answer, to see if he knows. He's a former navy man turned plant operator, so he might have that knowledge.
 
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While the nuclear powering of Navy vessels, both carriers, and the different classes of submarines, does not have anything to do with supplying power to any grid, I still recall back in December of 2000 when I was in California to have my back worked on, I had a conversation with a retired alpha sub navigator, and I told him that one of my big concerns with nuclear is what could happen if a tsunami hit a costal region that had a nuclear reactor. And that I was both concerned about commercial reactors, and those on Navy vessels that were in port. He did not think the Navy vessels were anything to worry about and said that he considers the nuclear propulsion systems to be black boxes that are designed well and not part of anything he had to get involved with. My point is that if a reactor on a carrier or a sub were still hot enough from recent running to be requiring a flow of sea water to keep it properly cooled, and that vessel were to be picked up and carried ashore and set down and then the water drained away, it may be that they find themselves with an uncontrollably meltdown. To that extent I think it should be mandated that before any such vessel reach ports or for that matter shores where a tsunami could possibly leave it tossed onto dry land, the reactor(s) be cool enough to not require any cooling from sea water. And this requirement may not be necessary at some island ports if the combination of the layout of the port, the island, and the ocean including systemic activity sites meant that there was really no chance of that problem happening at that location.

I know that just the idea that something could be powerful enough to carry a vessel that large inland is almost outrageous, but the way big ships were tossed around in the Japan tsunami shows that it is not impossible.

I know the Navy is meticulous when it comes to nuclear power safety, but I still have to wonder if a tsunami is something that could cause a serious problem with a nuclear powered vessel that was in port or near shore when it hit.

I know it sounds far fetched and like a one in a million chance, or maybe it is more like 1 in 10 trillion, but it is not zero. Heck, just the possibility of a tsunami is a very very low chance. But back in 2000 I was also concerned about the possible effects of a tsunami effecting commercial units and that was before the Fukushima Daiichi disaster.

One of the things that stays in my mind is a history channel show I once saw about how far inland and at what elevation, evidence of a tsunami wave exists in a few places on the U.S. west coast. While I do not recall the specific data, the distance and height was way beyond what most people would expect.


The 2011 Japan tsunami reached up to 133 feet.

Sometimes no matter what is done the unthinkable happens. There were discrepancies at Fukushima but would a taller sea wall have helped? A 9.1 earthquake is a monumental occurrence.
 

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The 2011 Japan tsunami reached up to 133 feet.

Sometimes no matter what is done the unthinkable happens. There were discrepancies at Fukushima but would a taller sea wall have helped? A 9.1 earthquake is a monumental occurrence.
Yes, yes it would. The sister plant closer to the epicentre that had the much higher seawall fared just fine.
 
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I know it varies with different reactor designs but in general after shutdown there is a significant percentage of heat still being generated for many hours. And that is often enough to be seriously concerned about, because it is enough to cause huge climbs in temperature if it is not removed. That is the Achilles heal that could cause a disaster with a unit that was shutdown recently and then lost cooling. It is NOT like an internal combustion engine where you turn off the ignition and everything goes to sleep.
 

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To add some data that might help visualize some of the stuff mentioned in the OP:

This wind output diagram is from a particularly bad period of wind generation during the summer in Ontario:
Screen Shot 2021-01-10 at 10.55.42 AM.jpg


You can see I include:
- Capacity (nameplate) which is just under 5,000MWe
- Average Output (this is Capacity adjusted for CF for the period)
- Capacity Factor
- Output for the period (MWh)

This is the overall plot of wind in Ontario for 2020. You can clearly see the spring/fall surges and the summer lulls:
Screen Shot 2021-02-01 at 11.39.46 PM.jpg


Here's another type of graph, this is generation output by source plotted against demand:
Screen Shot 2021-02-02 at 12.53.59 PM.jpg


And here's Darlington from last year when all units were online:
Screen Shot 2020-07-27 at 5.03.06 PM.jpg


I typically plot Darlington instead of Bruce because Bruce is a lot more work (double the number of units) and the amount of power it produces is just ridiculous. Even with a unit that went down for maintenance just over half-way through the period, average output at Bruce was north of 6,000MW and it produced >2TWh:
Screen Shot 2021-02-21 at 7.25.09 PM.jpg
 
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I’m with Miller88 on thinking nuclear is a good idea, but in my area supplemented with solar+battery backup on a home level.

Interesting when you look at OK's first post.

If there's 1,000MW of thermal...OK, let's say "schedulable" power, i.e. the Grid can dial the load up and down, so Nuke, coal, Gas thermal, Combined cycle, biomass, geothermal, their market can be cut out by 6-700MW of solar....in Oz, they are often being forced to PAY to generate during the middle of the day as renewables bid in at zero, or negative prices pull the daytime load out.

BUT it takes 3-4,000 MW of solar, plus batteries to replace it....then it becomes VERY VERY expensive, levelised cost of storage for a free KWh means that it costs 25c to store and retrieve on an Li battery.

Oz rooftop solar is getting about 10c/KWh at the moment versus around 30c if you are buying it....but as the rooftop capacity increases, there is serious talk about the householder paying to feed into an oversupplied, negatively priced market.

Peak demand (evening) has been flat for 7 years, but average is down markedly.
 

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Interesting when you look at OK's first post.

If there's 1,000MW of thermal...OK, let's say "schedulable" power, i.e. the Grid can dial the load up and down, so Nuke, coal, Gas thermal, Combined cycle, biomass, geothermal, their market can be cut out by 6-700MW of solar....in Oz, they are often being forced to PAY to generate during the middle of the day as renewables bid in at zero, or negative prices pull the daytime load out.

BUT it takes 3-4,000 MW of solar, plus batteries to replace it....then it becomes VERY VERY expensive, levelised cost of storage for a free KWh means that it costs 25c to store and retrieve on an Li battery.

Oz rooftop solar is getting about 10c/KWh at the moment versus around 30c if you are buying it....but as the rooftop capacity increases, there is serious talk about the householder paying to feed into an oversupplied, negatively priced market.

Peak demand (evening) has been flat for 7 years, but average is down markedly.
There would definitely need to be something like smart meters to help balance the load on the grid, but in my case I want to be able to operate independent of the grid in the case of a power outage (I’m still getting used to being on a well!).
 
Some recent back-and-forth's seemed to hint at the idea that we might want to discuss power generation in a bit more depth given the push for electrification and confusion surrounding some of the terminology. I'll preface this with the fact that I'm personally very pro-nuclear and pro-hydro but they each have their own merits and detractors just like any other source.

****If you are incapable of behaving yourself and contributing to a productive conversation, please don't bother posting.****

In terms of actual thermal plant operation, @Shannow has likely forgotten more about this topic than I know, but I don't think we need to get that deep.

First off, before getting into the sources themselves we should clarify some language that is regularly used and that quite often, the media uses incorrectly, swapping MW for MWh and similar.

Nameplate Capacity: Often abbreviated to just "capacity". This is the installed capacity for a specific source, typically in MW. It can apply to a single unit or as a whole, so a wind turbine can be 3MW or wind capacity can be 5,000MW speaking as to all units as a collective on a given grid, farm...etc.

Output: This is the amount of power a facility or generation unit produces, expressed typically in kWh, MWh, GWh, TWh. So, for example, a 1,000MW Nuclear reactor could theoretically produce: 1000x24x365=8,760,000MWh; 8,760GWh; 8.76TWh a year.

Capacity Factor: This is the amount of output, relative to Nameplate Capacity, that a facility or unit actually produces. So, that 1,000MW unit above, US nuclear units have an average CF of 93%, so in terms of Capacity that means 930MW, or in terms of Output 8.15TWh a year.

Each source we are going to discuss has wildly different capacity factors, which in turn means that their Installed Capacity (Nameplate) will not align with their relative contribution. This creates a lot of confusion particularly when we bring in things like Anticipated Capacity, which is essentially just a snapshot of CF for a specific period rather than the whole year.

Getting into the sources themselves now:

1. Nuclear
Pros:
- Very high Capacity Factor (highest of any source)
- Very predictable output
- Excellent baseload generator
- Small footprint
- Very cheap fuel
- Very low fuel consumption (refuelling period is typically every 18-24 months for a US PWR/BWR)
- Very high fuel security (fuel is stored on-site, so not vulnerable to supply disruption issues)
- Hardened and secured facilities are typically less vulnerable to weather related issues

Cons:
- Extremely high CAPEX (expensive to build)
- Relatively high OPEX (nukes have a considerable amount of staff)
- Poor load following capability (nukes can load follow, see: France, but economics are impacted, and fuel cycling becomes more frequent, lowest OPEX is baseload)
- Large unit size means that a single unit trip results in considerable capacity disappearing
- Long-term management of waste/used fuel, despite small footprint, will be required post-decommissioning

2. Hydro
Pros:
- High capacity factor (usually 60-80%)
- Very predictable output
- Excellent baseload generator
- Excellent load-following generator
- Excellent peaking generator
- Zero cost fuel
- Extremely low OPEX
- High fuel security (draughts that impact hydro output are reasonably rare)
- Hardened and secured facilities (dam operation centres are often inside the dam or in robust buildings nearby. The units themselves are contained.)

Cons:
- High CAPEX (expensive to build)
- Geography dependant (cannot be built everywhere)
- Extremely large footprint (reservoir setups)
- Large environmental impact for reservoir setups (run of river is better, but has no reserve capacity)
- Vulnerable to long-term supply shortage, IE, rare draughts that reduce water availability
- Cannot run at 100% constantly due to water flows/reservoir capacity
- Permanent landscape/nature/water disruption even after facility is EOL

3. Coal
Pros:
- High capacity factor (usually next after nuclear)
- Excellent baseload generator
- Decent load-following generator
- Low OPEX
- Low CAPEX
- Good fuel security (coal is stored onsite)
- Relatively self-contained facilities are typically very low in terms vulnerability to extreme weather-related issues

Cons:
- Poor peaking generator (slow ramp)
- Relatively high footprint if significant coal is kept onsite or plant is adjacent to mine
- Very high emissions footprint (highest of any source)
- Extended supply disruptions could impact generation (if coal is shipped or brought in by rail)

4. Gas
Pros:
- High capacity factor (particularly with steam thermal plants and baseload CCGT's)
- Excellent baseload generator
- Excellent load-following generator (GT/CCGT)
- Excellent peaking generator (GT/CCGT)
- Small footprint
- Low OPEX
- Low CAPEX
- Relatively self-contained facilities can be setup to be of low vulnerability to weather events

Cons:
- High emissions footprint (lower than coal, but that's not setting the bar very high)
- JIT delivery of fuel means extremely vulnerable to supply disruptions

5. Wind
Pros:
- Extremely low OPEX
- Extremely low CAPEX
- Small footprint (per unit)
- Low lifecycle emissions (similar to nuclear)

Cons:
- Tends to produce out of phase with demand
- Variability means it must be backed 1:1 relative to nameplate, typically with gas
- Susceptible to extreme weather (extreme heat w/no wind, extreme wind: turbines shut down, extreme cold w/no wind...etc)
- Medium-low capacity factor (~30-40% depending on location)
- Susceptible to seasonal variance not reflected in overall CF (summer CF can be quite low depending on geography, in the order of 12-15%)
- Short lifespan (~20 years)
- Diffuse (multiple generators must be installed over a large area to prevent shadowing and achieve significant installed capacity)
- Significant transmission requirements due to the above

6. Solar
Pros:
- Relatively low CAPEX
- Extremely low OPEX
- Reasonably low lifecycle emissions (about double that of hydro)
- Output tends to align with a large portion of daytime peaking requirements during the summer months
- Can be roof-mounted

Cons:
- Low density
- Large footprint (commercial, 10MW nameplate can take up almost 200 acres)
- Extremely low capacity factor (12-24% depending on latitude)
- Even lower winter capacity factor
- Short lifespan (~20-25 years)
- Susceptible to extreme weather (hail damage for example)
- Variability in output means it must be backed with either storage to cover the morning/evening ramps or 1:1 capacity in the form of gas


I'm sure there are some I've forgotten.

So, let's say we want to replace 5,000MW of baseload coal with wind.
- We would not install 5,000MW of wind, because on average, at say 33% CF, that 5,000MW of wind would produce 1,650MW.
- We'd install significantly more nameplate wind capacity than the coal capacity we want to replace to give us our average of ~5,000MW, on the order of about 15,000MW, which would provide similar annual output to the coal plant.
- We'd firm it with fast-ramp GT gas capacity of ~5,000MW nameplate that would fill for when it isn't windy. We'd also be able to export wind when output was higher than planned capacity, or curtail it if nobody needs it, at low cost.

The above is how you get into a situation where in terms of installed capacity, wind is one of the largest generators, but in terms of actual sources of electricity, may be quite a ways down the list. I'll use Ontario as an example, from this page:
Overkill, do you know if Indian Point #3 near New York City is going to get shut down this year? Unit # 2 was shutdown last year. I can’t find any updates on the net.
 

OVERKILL

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Overkill, do you know if Indian Point #3 near New York City is going to get shut down this year? Unit # 2 was shutdown last year. I can’t find any updates on the net.
There was supposed to be an NRC meeting on it:

But it was cancelled. It looks like it is proceeding however, based on the transcript of the last meeting:

(Ray Lorson): Thank you, (Brett). Good evening. As mentioned, my name is (Ray Lorson), and I’m the Deputy Regional Administrator the inner-cities region, one office located in King of Prussia, Pennsylvania. Our region has the lead role in the NRC for oversight of the Indian Point site. Our role includes both the oversight of current operations and extends through the decommissioning process on expected shutdown of unit three in the spring of 2021.
 
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