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Post by cyrilr on Apr 20, 2023 23:51:02 GMT 9.5
Pit thermal energy storage. www.sciencedirect.com/science/article/pii/S2352152X22017042Various succesful projects around, especially in Denmark. Seems the cheapest option yet - dig a hole, at an angle below the angle of repose of the local soil so it doesn't need expensive ground reinforcements, line with cheap durable plastic and insulating floating cover. Would make for a decent cheap dump load for otherwise curtailed wind and solar. Would also be interesting to consider a molten salt thermocline version - with stainless steel liner and refractory insulation but otherwise the same idea. I'm going to work on that.
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Post by cyrilr on Apr 20, 2023 20:29:31 GMT 9.5
Yeah, basically the investors are getting rich on high interest rates on the money they borrow. Which means they stand to gain on cost overruns and delays - them being at the receiving end of those cost overruns. Ditto for contractors - more re work Means more money for them. And even the regulator gets paid by the hour so they also benefit from delays. A pervese situation. Capitalism has failed nuclear new builds in the West.
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Post by cyrilr on Apr 19, 2023 14:41:10 GMT 9.5
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Post by cyrilr on Apr 19, 2023 8:28:03 GMT 9.5
… the Chinese EPRs are just as complex … Nope. The Chinese EPRs might be called EPR1 design, modified to have additional, expensive safety features for the Finland EPR, call it EPR2. Then further modified for the EPR under construction in France, say EPR3. The French engineers say it is too complex and have designed what I’ll call EPR4 for further construction, if any. Please provide engineer source for this. I’m a nuclear engineer and these designs look nearly identical to me. In fact I have difficulty finding where all the money goes. If you could provide a breakdown of costs better than “nope” I would be much obliged.
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Post by cyrilr on Apr 18, 2023 18:40:57 GMT 9.5
Europe’s largest nuclear reactor enters service in Finland 2023 Apr 16 Phys.org techxplore.com/news/2023-04-europe-largest-nuclear-reactor-finland.htmlThe third EPR to be completed, after 14 years of delays. In my opinion, the EPR is far too complex as, being large, it requires extensive safety features unnecessary for SMRs. But at least it is now available to produce 30% of Finland’s electricity for the next 60+ years. The problem with that opinion is that the Chinese EPRs are just as complex (basically technological clones) yet they were built on time and budget. To me it is obvious that the real problems are in how things are done rather than what. That is where lessons should be learned. Sadly, because that is mostly politically, socially and legally engrained, we are unlikely to learn anything. Indeed; people’s jobs depend on not learning this. Future EPRs built in the West will be plagued by more delays and cost overruns. Heck we will pat ourselves on the back for it. Mark my words.
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Post by cyrilr on Apr 15, 2023 0:18:05 GMT 9.5
Why China Could Dominate the Next Big Advance in Batteries Kieth Bradsher 2023 Apr 12 The New York Times www.nytimes.com/2023/04/12/business/china-sodium-batteries.htmlSodium batteries are much less expensive than lithium batteries but have only about half the energy storage per unit weight. Perfectly suited for stationary applications; possibly useful for some of the batteries in less expensive automobiles. You can mix and match as well. For example a high end EV would Use mostly lithium and some or even no sodium batteries. A mid range model would be perhaps half and half. Then the entry level EV would use only sodium to cut costs. That makes for a great stepping stone approach, where you can get some production economics going and get rolling along the learning curve, and as sodium energy density improves you put in more and more sodium, gradually phasing out lithium over decades. Lithium is not going to sit back and read the newspapers though. It will improve as well. Nice arms race. Competition is good.
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Post by cyrilr on Apr 14, 2023 18:02:24 GMT 9.5
Not really the right thread though. My concerns are on a global scale - powering the world is about more than putting up enough wind and solar, it has to be connected to a grid. Delivered when and where it is needed and spatial and temporal mismatch must be resolved at local, regional and national level at every second, minute, hout, day, year heck decade. If we need to 5x global electric transmission infrastructure to make a wind and solar powered world then that is a huge red flag and a total non starter for renewable energy. And 5x may be a severe underestimate. See Devanney’s paper. Most of the renewable energy is dumped to make a predominant wind and solar grid. But you need the grid capacity to dump loads as well. We could well be looking at 10x electric grid capacity. Which is firmly in the “ forget about it” category.
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Post by cyrilr on Apr 14, 2023 1:11:17 GMT 9.5
One major issue that is almost pathologically ignored by renewables enthusiasts is how to get power from wind and solar generators to the end user. Musk is saying we need 30 TW of wind and solar plus batteries. He ignores the transmission issue entirely. 30TW several times today’s global electric grids capacity. That is like rebuilding all electric grids, built at great cost and effort over the last few centuries, several times over - in the span of mere decades!!
1. What will this cost 2. Who will pay for it 3. How much steel, copper, aluminium and other metals, not to mention fossil fuels, are required to build, operate and maintain this future behemoth grid?
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Post by cyrilr on Apr 1, 2023 21:13:24 GMT 9.5
BWRX-300 is probably about as simple as an LWR gets. Direct cycle natural convection boiler with dry containment. Being smaller means easier financing, at the cost of higher $/kW. Simplifications such as dry containment and silo construction should mitigate the cost but it will always be more expensive than bigger plants. Nukes have such strong scale economies, even more so today due to endless red tape and bureaucracy (which costs the same for a small reactor thus blowing out $/kW almost proportionally). Project in Poland should have less red tape. The projects in Canada are fairly hopeless in this respect. The Canadians are gleefully taking 50 years just to figure out where to put a repository, with endless stakeholder engagement and other woke nonsense.
GE-H developed the SBWR previously and that went nowhere. Then they developed the ESBWR from that and that went nowhere. Let’s hope three times is a charm.
Kind of funny how they consider it the tenth generation. 8th and 9th generation were not built. I don’t see how paper reactors (even licensed ones) count as a product generation.
I would prefer the Kerena reactor over the BWRX. More output, more efficiency, and no reliance on valves for core cooling (isolation condensers have lots of valves). Plus the pressure pulse transmitters allowpassive switching which GE-H product doesn’t have.
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Post by cyrilr on Mar 29, 2023 19:33:09 GMT 9.5
Running a capital intensive steel making plant intermittently at 10 or 20% capacity factor is not a break through. It’s economic nonsense. No sane investor would get behind this, when he or she could invest in the same plant running on 24/7 reliable baseload power and make 3X or 5x the revenues. Low temperature is definitely the way to go, though, whenever feasible. People have been trying for over a century and failed. Don’t hold your breath.
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Post by cyrilr on Mar 24, 2023 18:20:13 GMT 9.5
So the author published an article on high cost using a figure that wasnt a cost figure. The entire premise of his article was false. An honest author would retract the article. He just put in a footnote.
Axes to grind. Is there an anti nuke out there who doesnt have them?
I will concede one point. 20 MW is too small.
That is not the key issue however. The key issue is how things are done. Not how big the reactor is. Nukes cost under $300/kWe in the early days. That was FOAK costs as well. The same LWRs as we have today. What has changed is how things are done. Red tape. Massive double standards. ALARA aka good is never good enough so lets spend more. Safety fascism. Pretentious “we are nuclear we are special” attitudes. These are the things that make nuclear expensive. And ironically leads to low quality.
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Post by cyrilr on Mar 20, 2023 0:12:27 GMT 9.5
www.ecovat.eu/These guys over here want to store hot water in big underground tanks on seasonal scale. Simple and low visual and environmental impact. They claim it is cheap but their own estimates suggest prices in the ballpark of 20000 euros per household. That is very expensive by any comparison. A gas boiler is 2000 euros installed. They probably have to scale the tank up. A lot. To get cost down.
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Post by cyrilr on Mar 18, 2023 0:02:20 GMT 9.5
Author makes several salient points. Most hydrogen initiatives bleed out, and even the rare successes seem to only find niche uses. We will need a lot of hydrogen for industry. Replacing coal in steelmaking with hydrogen is a huge demand driver further in the future, unless direct high temperature or aqeous electrolysis turns out the winner. Disagree with his view on biofuels. These are part of the problem and should not be encouraged other than for niche and mainly local uses (re use of waste streams etc). Using biofuels for energy is also very inefficient, such complex molecules shouldn't be burned, they should be used for bio materials, medicine etc. Synthetic fuels (made with high temperature nuclear reactors) are a much better means of powering long distance travel like planes and boats. Not terribly efficient compared to electric vehicles but it's hard to see intercontinental flights and supertankers going about on batteries, even with large improvements like lithium-air etc.
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Post by cyrilr on Mar 14, 2023 17:46:54 GMT 9.5
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Post by cyrilr on Mar 14, 2023 17:28:16 GMT 9.5
VAWTs are uncompetitive due to lower generation from lower efficiency compared to HAWTs. Micro turbines are less efficient and have lower capacity factors. We tried them here in a windy location next to the sea with no obstacles. They got like 1 to 3% capacity factors. In a residential area it would be worse. It’s dumb, and proven so. Putting two bad ideas together does not a good idea make.
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Post by cyrilr on Mar 14, 2023 17:04:33 GMT 9.5
What about the ozone layer then?
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Post by cyrilr on Mar 14, 2023 1:35:44 GMT 9.5
Inside the Global Race to Turn Water Into Fuel Max Bearak 2023 May 11 The New York Times www.nytimes.com/2023/03/11/climate/green-hydrogen-energy.htmlIn remote West Australia there is plenty of sunshine and wind. There are customers for transportable energy to power the ultra-large mining machinery, iron ore haulers, and batteries won’t suffice. So the plan is to produce so-called green hydrogen via electrolysis of sea water and consume it right there in the haulers. Looks quite feasible. Have always been sceptical of green hydrogen schemes. Hydrogen production plants are industrial facilities. They are run 24/7 to recover the large investments. Capital intensive. Running them at 20% capacity factor (when the sun is shining) makes the CAPEX 4x higher than running it at 80% (as in a grid connected system powered by reliable power). Even if your energy cost is very low, it is hard to survive such a large CAPEX disadvantage. Any investor would prefer to have the hydrogen plant be grid connected so it can run at a high capacity factor. Which means it won't be green, other than in the usual accounting fraud of "renewable energy credits". Seems to me that this is the direction things are going. Pretend green hydrogen that actually comes from fossil power.
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Post by cyrilr on Mar 12, 2023 20:40:41 GMT 9.5
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Post by cyrilr on Mar 10, 2023 23:41:03 GMT 9.5
Pumped hydro in the desert? Where will they get the water? Huge problems already with Colorado water suppy & water rights.
Perhaps they can bring in seawater or contaminated waste waters.
In any case these are not long duration projects... high turnover is needed for economics and there are limits (geotechnical and economical) to the size of the upper reservoir.
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Post by cyrilr on Mar 9, 2023 3:20:26 GMT 9.5
Oops! I used the cooling formula and should have used the heating formula for COP: COP = (540+273)/(540-275) = 2.956 Still silly theoretical stuff. Just like Carnot limit. Real systems are way below this. Say you get 2. Then it is 0.45*2*0.45 = 40% efficiency. Thats a huge deal; way better than 33% PWR gets. Forget coal plants, you wanna make this a baseline for greenfield. But if it is closer to 1 then 20% or so. Not good. I suspect it is. Can’t even think about what this looks like. No one makes heat pumps in these tees. What refrigerant is suitable to these temperatures? Maybe you go for acoustic heat pumps using helium.
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Post by cyrilr on Mar 8, 2023 14:57:45 GMT 9.5
Units are degrees Celsius: For this application the heat pump has COP = (275+273)/(540-275) = 2.068 which seems poor, but the savings is in the reuse of the steam turbine and generator, considerable. That’s the theoretical COP. You never get that. What is the actual performance?
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Post by cyrilr on Mar 8, 2023 3:07:58 GMT 9.5
Yes, I guess you can view it that way. It will have a very low COP though as it is a high temperature heat pump. like close to 1 basically? Still makes little sense to me, using turbine power even at 45% efficiency to run a heat pump with low COP to generate more power in the same cycle. If it were something fancy like an acoustic heat pump with a COP of 2 then that would make some sense. Sounds expensive at these power levels as well.
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Post by cyrilr on Mar 7, 2023 19:07:40 GMT 9.5
I don’t get it. Using nuclear heat to make electricity at 33% efficiency, then using that to run a turbo at 90% efficiency, to make higher grade heat for a supercritical turbine at 45% efficiency. That’s 13% nuclear heat to electric efficiency. How is this a big idea?
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Post by cyrilr on Mar 7, 2023 2:15:11 GMT 9.5
But the renewables people keep telling me that solar now costs 2 cents per kWh in sunny areas and 4 cents per kWh in cloudy areas.
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Post by cyrilr on Mar 7, 2023 2:13:04 GMT 9.5
As an example here in Holland the average draw is about 15 GW and basically never over 20 GW. The LV grid takes only a fraction of that because households and small businesses use only a fraction of the electricity. Hard to find data but probably in the 5 to 10 GW range somewhere.
We get about 10% capacity factor with PV on rooftops (as little as 4% for badly installed ones, like facing north, with about 11% for ideally installed south facing). Using all rooftops we would have to use east and west and some north facing rooftops. We would get around 8% capacity factor.
To get 15 GW average over the year would need (15/0.08)= 188 GWp of PV (DC rated).
Putting 188 GW of intermittent uncontrollable power on a 5 or 10 GW LV grid. I don't know what to say. If we spend a fortune on resistance banks at every street corner and God knows how much in upgrading the LV grid. We'd have to go for industrial voltage (380V) probably. And we haven't supplied industry and heavy electric transport and so on, which guzzles half our electricity consumption. And we still get next to nothing in winter. We get about 1% capacity factor in Winter on average through the winter months. So 2 GW only. So we can't shut down our fossil plants. We'd need to install all this PV, make huge infra grid investments, and can't close down a single fossil generator basically.
How is this a plan?
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Post by cyrilr on Mar 7, 2023 1:56:51 GMT 9.5
Clever idea. Would be ideal w. Induction charging of the train. Flat panels are not great for Switzerland though. Would be better for rail in regions closer to the equator.
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Post by cyrilr on Mar 7, 2023 1:52:56 GMT 9.5
OK - I've been a fan of nuclear since you guys spent all that time with me learning the basics back in 2010? Forever ago. But now that we're here in 2023 there's a few things to note. Renewables have been on a economies-of-scale cost reduction to ridiculously low price. We used to ask how to do a 100% grid - and winter was a terrible bottleneck! It looked like you had to store power for months just to get through winter.Then as news of the price reductions got out and solar was 10% the cost of over a decade ago - I started to see a new trend in renewables papers. Massive OVERBUILD. That is, if winter halves your renewables output, then double your renewables! Don't even try 100% - do 200%! The modelling shows with enough HVDC transmission around Australia, and with decent overbuild, most places can get by with 2 days storage from off-river pumped hydro. If one spot has a really bad week in winter and uses up their 2 days, they can start to borrow storage from other places. There are all sorts of questions around this OVERBUILD strategy - but a number of independent models are starting to come together and say the same thing. But there might be reasons to attack these models - but this idea that there isn't enough land just needs to die! Consider - if we cover HALF the world’s rooftops with solar, it would provide all today’s electricity needs. theconversation.com/solar-panels-on-half-the-worlds-roofs-could-meet-its-entire-electricity-demand-new-research-169302 Cover ALL the world’s rooftops and you’ve got enough to electrify transport and industry. Singapore's Dr. Thomas Reindl points out that floating solar panels on just a tenth of human made fresh-water reservoirs is ALL today's electricity use. The solar panels reduce evaporation of our precious fresh water, and the water keeps the solar cool and efficient. If we cover ALL our water reservoirs it is 10 TIMES today's electricity! youtu.be/2hwpXCjmkRo So ALL our rooftops and ALL our water reserves would be 12 TIMES today’s electricity use. (And I haven’t even mentioned off-shore wind yet.) Even Japan with their huge population and tiny islands can power themselves 14 times over. Indonesia can float enough solar in their calm oceans to power THE WORLD. This myth that solar and wind will take up too much land just needs to die - and it stinks of fear from big oil. I'm still a fan of nuclear but Lazard says renewables are 1/4 the cost of nuclear. That's plenty of room for overbuild in Australia - even if as Professor Andrew Blakers says 15% of the cost is storage, 15% is transmission - and the other 70% is wind and solar. It's just so cheap! By the end of the year solar could be 1/5 the cost of nuclear per kwh. AND I KNOW that's not the same as baseload - but that's the raw data we feed into the models that calculate it all based on Australia's weather over the last 40 years. (Griffith's Uni does this.) It still comes up around $70 per mwh - but could be heading down cheaper and cheaper. Nuclear industry in the Wst screwed itself up royally, for sure. China, Russia and S Korea seem to be the only suppliers that kept themselves sane and capable. But I don’t see how fitting 500 GWp of solar on the LV grid in a grid with 100 GW average draw is going to work. Like trying to put a 500 hp engine in 100 hp car. Ya gonna break it unless you replace literally everything. Here in Holland we get 10% capacity factor from pv. So we need 900% overbuild. That’s crazy. Utilities are already complaining about the overloaded LV gird at 10% penetration. You would need resistance dump banks at every street corner for this to work. And then you are dumping most energy generated. Which is also crazy. And you still generate nil power in winter - right when energy demand peaks...
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Post by cyrilr on Nov 17, 2021 5:34:26 GMT 9.5
A simple case in point.
My own country of Holland. We have a need for about 120 billion kWh/year, over 13 GWe average draw.
We can probably accomodate some 10 GWp of solar PV with some serious investments in grid upgrades. We have a lot of gas turbines which can accomodate big swings though some plants are must-run, cogen and steel related so that's a problem but let's ignore that to be kind to PV.
We get about 10% capacity factor fo PV. The best systems, ideally angled towards the south, and regularly cleaned get about 11%, but many systems are east or west facing and not so often cleaned so would get 7-9% capacity factor. Let's use 10% as a typical fleet average.
Our 10 GWp of solar PV only generates 1 GWe average on the year. So it provides under 1/13th the electrical energy or some 7% of total electrical demand.
The problem, as you might have noticed, is that we haven't addressed 93% of the problem, which is going to have to be mostly single cycle gas turbines throttled very inefficiently. Almost all coal stations will have to be shut down, which is a good thing on the environmental side, though not much help on the CO2 emissions side, since throttled peaker gas turbines emit almost as much CO2 per kWh as a coal plant.
You will have noticed that the vast majority of this "solar" grid is powered by natural gas, used very inefficiently in single cycle gas turbines.
Now, as a matter of fact, the CO2 emissions would be less if we powered most of the demand using efficient dual cycle gas-steam turbines for mostly baseload and load following service. Ironically, this would have a LOWER CO2 emission than the solar-gas grid.
The main point being that low capacity factor, intermittent, non-dispatchable solar energy sources only serve to lock us into using fossil fuels (very inefficiently) for as long as the solar energy sources persist. Which, I'm told, is forever since it is renewable.
Ouch. Reality hurts!
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Post by cyrilr on Nov 15, 2021 20:07:02 GMT 9.5
Yes, ignoring the two biggest problems can make any plan look feasible. If we ignore mortgage and energy bills, everyone can live in a Mcmansion! The article states 40% variation between winter and summer for northern latitudes. This is wrong. More like 4000% variation between best vs worst day. Here in Holland a winter day is 0 to 2% capacity factor. You cannot install 100 GWp of solar into a 20 GW grid. Such simple facts and logic is lost to entire nations, corporations and billionaires.
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Post by cyrilr on Aug 29, 2021 2:12:49 GMT 9.5
Uh, well technically, the conditions in the heart of the sun are rather different, in pressure, temperature, and even the fusion fuel type...
This is closer to what is happening in a nuclear weapon.
Of course, that's not very nice PR.
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