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Post by David B. Benson on Jul 23, 2019 19:18:07 GMT 9.5
A thread about providing enough power for the future. Not just electricity but space heating and cooling, transportation and industrial, also commercial, requirements. We start with So You Think We Are Reducing Fossil Fuel Use? Think Again James Conca 2019 Jul 20 Forbes www.forbes.com/sites/jamesconca/2019/07/20/so-you-think-were-reducing-fossil-fuel-think-again/#5d2d756952fbWherein Dr. Conca suggests --- stop building new fossil fuel plants ASAP --- 35,000,000 new MW of wind turbines --- 1,400,000 MW of new nuclear reactors, particularly SMRs which are especially ideal for load-following renewables --- 2,100,000 MW of new solar --- 1,200,000 new MW of hydro w/80,000 MW existing All but the last point I nod yes to. But hydro schemes ruin rivers. Instead build that much more nuclear, solar and wind power plants, for a much smaller cost. But also think about desalination: www.forbes.com/sites/jamesconca/#5d15ebfc6b07The desalinated water can be used for the Rankine cycle cooling water. Don't just evacuate to the atmosphere but capture the water vapor for later beneficial use.
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Post by Roger Clifton on Jul 23, 2019 21:54:57 GMT 9.5
Given a sufficiently frightened global political climate, it would be possible to replace thermal power stations as fast as nuclear reactors can be manufactured and assembled on site. The world would have to somehow accelerate the production of pressure heads, massive lids for the reactor pressure vessels.
The main attraction of SMRs is that they are designed so they can be factory built, thus enabling mass production. Arriving on a truck, already assembled, they are essentially ready to plug and play. They are also easily adapted to air cooling, thus replacing open cycle gas turbines. The bottleneck would then become the shortage in trained operators.
It would be contradictory to be adding renewables in a world that had sounded the death knock for all open cycle gas turbines. Constraining a nuclear plant to stop production so that a nearby solar or wind farm could inject noise into the grid, need only be a temporary political measure, perhaps until the panels or turbines obsolesced.
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Post by engineerpoet on Jul 24, 2019 0:49:36 GMT 9.5
The world would have to somehow accelerate the production of pressure heads, massive lids for the reactor pressure vessels. There are only a few forges in the world big enough to make RPVs for gigawatt-scale LWRs, and they're fully subscribed already. You'd have to add the lead time to build new forges to the timeline for even beginning that acceleration. NuScale gets around this by radically downsizing the RPV. LMFBRs and MSRs operate at close to atmospheric pressure. They may be the future just because of manufacturing issues. Dunno where you got this "air-cooled" idea. I started digging into the question of what it would take to do dry cooling with a natural-draft tower for a LWR but I couldn't find data on density and enthalpy increase in conventional wet towers so I had no basis from which to calculate the required buoyancy and flow for a dry tower. If the Highview Power LAES scheme gets traction as a buffer in RE-heavy areas, it'll also prevent the NPPs from having to throttle back; it'll be the fossil plants that get idled instead. 10 hours of buffer is plenty of time to get a gas-fired plant from cold shutdown to full power. That may be just what we've been looking for all this time.
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Post by Roger Clifton on Jul 24, 2019 9:27:51 GMT 9.5
Dunno where you got this "air-cooled" idea Well, then you don't know. Check out the facts before you disparage a comment, please. Air cooling is in fact a standard technique, used in water-constrained areas such as at Kogan Creek PS in inland Queensland. Air cooling is unpopular elsewhere because its fans consume ~5% of the output power. There are increasingly hybrid systems, allowing for a weaker air flow with water being reserved for times of greatest heat stress.
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Post by engineerpoet on Jul 24, 2019 11:50:06 GMT 9.5
Air cooling is in fact a standard technique, used in water-constrained areas such as at Kogan Creek PS in inland Queensland. Air cooling is unpopular elsewhere because its fans consume ~5% of the output power. I meant "where did you get that air-cooling was an option for SMRs?" Because it looks like nobody's even thinking about selling that as a feature yet. Air cooling doesn't have to use power for fans; you can run a natural-draft tower either wet or dry. The problem is going to be higher condenser temperatures and consequent turbine back pressure, so the turbine design may have to change to leave off an expansion stage or two. You're also going to take a serious hit to the thermal efficiency, but uranium is cheap enough that the impact on the capital cost per kW(e) probably matters a great deal more. As I said, I started digging into the question of what it would take to do dry cooling with a natural-draft tower. You need X000 MW of heat-rejection which requires Y kg/sec of air flow at Z degrees K temperature rise divided by 1005 J/kg/K constant-pressure specific heat. The buoyancy of the air in the tower is proportional to Z, the temperature rise. If I could get a representative operating point for even a wet cooling tower, just the inlet and outlet temperature and humidity and thermal power, I could come up with ballpark figures for this. So far I've not discovered anything detailed enough to use. I gave up.
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Post by Roger Clifton on Jul 24, 2019 13:56:30 GMT 9.5
I meant "where did you get that air-cooling was an option for SMRs?" Because it looks like nobody's even thinking about selling that as a feature yet. When commenters speak with such authority, we need to trust that they know what they are talking about. Rather than assert an unchecked factoid, it would be safer to say, "As far as I know...." In fact, mPower planned for 31% efficiency with air cooling. Holtec has a design with air cooling for the SMR-160 too. Toshiba's 4S had an air cooled option for desert locations.
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Post by David B. Benson on Jul 24, 2019 17:30:54 GMT 9.5
Back to a previous topic:
In an Energy Only grid such as ERCOT Texas, the ISO accepts offers to generate in so-called merit order, i.e., lowest cost energy first, up to the required total generation. Then all generators are paid at the highest accepted rate.
The generators offer, typically, the LCOE of the equipment, plus, I assume a very small profit. This has the general effect of accepting the bids from solar PV first, then from wind farms and lastly other sources to meet the demand. I simplify by leaving out hydro and also solar thermal, etc.
The effect is that the thermal generators must load follow. Coal burners can't and so go out of business. Just now in the USA gas turbines generally do fine, certainly so in ERCOT Texas. Many conclude that new nuclear power plants must load follow in order to have a role. Of course, one might find another market for the generation not going to the grid.
To be clear, this is market driven not political. It works the same way in locations without subsidies for certain forms of generation.
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Post by Roger Clifton on Jul 25, 2019 9:45:33 GMT 9.5
The generators offer, typically, the LCOE of the equipment, plus... I am puzzled here by the qualifier, "of the equipment", so perhaps you may be able to enlighten me. As I understand it, the LCOE includes the costs of fuel, carbon tax, rents on fly ash lakes and other costs external to the equipment itself. Thus a major part of the LCOE of say, an open cycle gas turbine should include the cost of gas delivered to the site. It does make sense to me that a generator would bid with a minimum price that would just cover all of his costs, yet keep him out of bankruptcy indefinitely. Perhaps I'm missing the point. In a fiercely competitive situation, an operator need only be able short-term to pay salaries and interest on the equipment until the debt collector comes knocking for the rest.
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Post by David B. Benson on Jul 25, 2019 9:59:34 GMT 9.5
Roger Clifton, yes, all the expenses making up the LCOE for each generator bid. May be different for each generator.
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Post by David B. Benson on Jul 27, 2019 15:56:08 GMT 9.5
Solar energy becomes biofuel without solar cells Elin Backstrom 2019 Jul 26 Phys.org m.techxplore.com/news/2019-07-solar-energy-biofuel-cells.htmlFinally have evolved cynobacteria to produce useful concentrations of butanol, a potential transportation fuel. Maybe this could actually scale up enough to make a difference.
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Post by David B. Benson on Jul 28, 2019 22:53:14 GMT 9.5
Scotland Renewables making enough Electricity to power Two Scotlands and other Wind Power Successes Juan Cole Informed Comment www.juancole.com/2019/07/wind-two-scotlands.htmlDespite the dizzy style this piece does inform one of new generation in other parts of the world. Scotland is the least of it.
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Post by David B. Benson on Jul 30, 2019 10:20:24 GMT 9.5
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Post by engineerpoet on Jul 30, 2019 12:31:09 GMT 9.5
This is but a solar cell with an evaporation unit right behind it to utilize the photons the solar PV is unable to capture. It's not using the photons, it's using the photon energy that's not converted to electric power. The band gap of most PV semiconductors is rather low and any photon energy above that is wasted. Low band gap means most photons get absorbed, but not much of their energy appears at the output terminals. So long as the cell type isn't much affected by increasing temperature it should work. Silicon would not be a good choice for this, IIUC. And of course you want a nice, impervious layer of something like glass between your cells and the saltwater.
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Post by David B. Benson on Jul 30, 2019 12:53:04 GMT 9.5
Yes, unusable photons produce just heat. If radiant heat, then far infrared photons. Otherwise, phonons.
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Post by David B. Benson on Aug 3, 2019 15:02:04 GMT 9.5
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Post by Roger Clifton on Aug 3, 2019 18:34:41 GMT 9.5
... prediction of vastly more batteries. Is there that much lithium? There is no shortage of lithium in the ground to make vastly more batteries. In 1970, I led teams with four geophysical tools to help delineate the pegmatite swarm at Greenbushes in Western Australia. Nearly 50 years later, that pegmatite is still producing and is currently the main source for the world's lithium consumption. However pegmatites containing spodumene (lithium mineral) are common all over the world. As demand increases, other pegmatites or brine lakes are being explored and opened up. Initially demand will be oversupplied, the lithium price will crash and only the mines that could produce at less than the market price of the day will stay open. Mineral exploration technology and mining technology have been advancing such that any mineral can be located and extracted at ever decreasing cost. Minerals now are a minor component of the cost of almost any product. Even the market price of that immensely valuable commodity, uranium is less than $100 per kilogram. If educated people ever tolerate the suggestion that "the world is running out of mineral X", we are not just wrong. We are allowing a dangerous deception to take place. Because there is absolutely no possibility that mineral non-renewables could ever run out, there is no justification for anyone saying that renewables are necessary to replace fossil fuels. The urgency is too great to indulge such ignorance, no matter how fashionable.
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Post by engineerpoet on Aug 4, 2019 8:02:33 GMT 9.5
Lithium is always going to cost more than air, though. Highview Power's LAES scheme looks like it uses cheap materials (plus a lot of air of course). Then there's "solar salt" storage for heat up to about 500-550°C, which is also much cheaper than lithium. Those really need to be the go-to solutions for stationary grid-scale energy storage, saving lithium for mobile applications.
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Post by David B. Benson on Aug 4, 2019 12:23:24 GMT 9.5
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Post by engineerpoet on Aug 5, 2019 4:55:04 GMT 9.5
Here she points to the backup problem and the resulting higher cost. That, plus the extra fuel burned during the more-frequent starts for fossil-fired plants, needs to be billed to the "renewables". They're currently, as my erstwhile co-blogger notes, freeloading on the rest of the grid.
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Post by David B. Benson on Aug 5, 2019 10:20:00 GMT 9.5
They're currently ... freeloading on the rest of the grid. Not in ERCOT Texas nor, I believe, in PJM or CalISO nor other grids with using the PJM two phase energy payment system; see the last post on the Simplified Grid Dispatching thread.
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Post by David B. Benson on Aug 6, 2019 22:15:18 GMT 9.5
Systematic high-resolution assessment of global hydropower potential Hoes et al. 2017 PLoS ONE v. 12 journals.plos.org/plosone/article?id=10.1371/journal.pone.0171844So by ignoring all the biological and other effects, about 50 PWh/annum, if all sites utilized fully. The authors state that this is 10x the current hydropower generation, worldwide. While good to know, I cringe at the thought of utilizing much more hydro. Too many unintended and unfortunate consequences.
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Post by engineerpoet on Aug 6, 2019 22:24:34 GMT 9.5
Not in ERCOT Texas nor, I believe, in PJM or CalISO nor other grids Yes, those places too. Anywhere that wind and PV are selling energy without compensating the rest of the grid for providing balancing services, reactive power and spinning reserve, they are freeloading.
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Post by David B. Benson on Aug 6, 2019 23:02:31 GMT 9.5
Anywhere that wind and PV are selling energy without compensating the rest of the grid for providing balancing services, reactive power and spinning reserve, they are freeloading. But such places, if any, do not include those RTOS using the PJM pricing scheme. Read the entire Introduction to Power Markets that I linked one chapter of in the Simplified Grid Dispatching thread. One method for wind farms is to include a nominal one hour duration battery. There is such not 2 km north of me and it works great; the lights never even flicker anymore during lightening storms. The one installed in South Australia to much fanfare proved it's worth during two grid transients of considerable size. I posted about this in the Australian Grid thread. A small unfairness that ERCOT generators must bear is that everyone pays for the entire transmission system. Since the longest and newest transmission lines are for West Texas wind farms, this appears to favor them. A larger unfairness, perhaps, is the PTC, Production Tax Credit, for wind turbines in the USA. This means the operators can still make money while paying customers to consume their power. This has led to serious market distortions on occasion; I still remember a famous one here in the Pacific Northwest.
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Post by David B. Benson on Aug 8, 2019 17:26:31 GMT 9.5
How much energy storage costs must fall to reach renewable energy's full potential 2019 Aug 07 Phys.org m.techxplore.com/news/2019-08-energy-storage-fall-renewable-full.html10x. That is, a tenth of the current cost. The piece implies this is improbable; I concur. So an alternative for fortunate locations is massive pumped storage. The late Roger Andrews wrote several threads about such on Energy Matters; one has to dig for those. This article states that the problem is the worst 5% of the time. What it fails to state, at least in this summary, is those worst times happen during the hottest summer weeks or the coldest in winter. A solution is a variation on peakers, which rarely provide power and so that for a very high price. Usually those produce carbon dioxide.
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Post by David B. Benson on Aug 12, 2019 16:05:06 GMT 9.5
One of the world's largest banks thinks the writing is on the wall for the oil industry Joe Romm 2019 Aug 09 Climate Progress thinkprogress.org/oil-faces-irreversible-decline-thanks-to-electric-cars-and-solar-warns-worlds-8th-largest-bank-d128101ef4a8/So with a pricing scheme for retail electricity akin to that for the wholesale market, one charges the EV battery when electricity is the least expensive. Always, that is overnight but where solar power has been overbuilt, also midday. Such developments make it easier for constant producers such as nuclear power plants. This is easy to see for increased overnight demand, flattening the demand curve. As for midday, the increased demand would tend to flatten the "duck's back in the so-called California duck curve, possibly raising prices toward flat. So bring on EVs to diminish the oil industry!
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Post by engineerpoet on Aug 13, 2019 0:46:02 GMT 9.5
So with a pricing scheme for retail electricity akin to that for the wholesale market, one charges the EV battery when electricity is the least expensive. Always, that is overnight but where solar power has been overbuilt, also midday. That assumes you have a choice in the matter. If you have an EV, you have to charge every X miles or you are stranded. The smaller the battery, the fewer your options. Cloudy day? Gotta charge anyway. The limitations on battery manufacturing (particularly cobalt) are going to drive things away from full EVs and toward PHEVs and down to HEVs. PHEVs are great (I own one) but they have to be charged as frequently as every 15-20 miles to get the maximum benefit from carrying that battery. Needless to say, you don't get much choice about when to charge it, so waiting for a period of solar or wind power is a luxury you cannot afford. I calculated what it would take to level the German PV generation peak using Chevy Volts. I came up with something like half a car per capita, and that was at the PV penetration of some years ago. It would take considerably more now. Doing a BOTE calculation for the USA, assume half the LDV fleet (125 M cars) carries 10 kWh each and fully charges it all every night between 9 PM and 7 AM. That comes to 1.25 TWh over 10 hours or 125 GW average. This is more than the nameplate generating capacity of all the USA's nuclear plants. Interestingly, it looks easier to do this with nuclear than solar. They are all "energy companies" now, with interests including natural gas. Natural gas is the obvious buffer fuel to provide that on-demand electric generation during the day. In short, they are going to get theirs.
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Post by David B. Benson on Aug 14, 2019 18:10:49 GMT 9.5
Study: all major Chinese cities capable of generating solar power more cheaply than grid Bob Yrka 2019 Aug 13 Phys.org m.techxplore.com/news/2019-08-major-chinese-cities-capable-solar.htmlAll 344 cities and without subsidies. Cheaper than coal. Tsinghua University is a major institution so I suppose these claims are justified. Despite this being what the state planners want.
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Post by David B. Benson on Aug 14, 2019 18:57:04 GMT 9.5
Growth of wind energy points to future challenges, promise 2019 Aug 13 Phys.org m.techxplore.com/news/2019-08-growth-energy-future.htmlNot a word about birds and bats. As for promoting grid stability, yes, with very expensive power electronics the inertia of wind turbines can be utilized. But less expen is to attach a low capacity battery to each wind farm for what are called ancillary services.
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Post by engineerpoet on Aug 14, 2019 20:35:31 GMT 9.5
Study: all major Chinese cities capable of generating solar power more cheaply than grid Does that include the cost of keeping the coal-fired plants on standby for all the times that the solar units are NOT generating? Rhetorical question. That's always Somebody Else's Problem. Edit: As I expected, the full paper is paywalled. Can't see the details to critique them without shelling out dough.
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Post by David B. Benson on Aug 15, 2019 17:49:50 GMT 9.5
Europe has the untapped onshore capacity to meet global energy demand 2019 Aug 14 m.techxplore.com/news/2019-08-europe-untapped-onshore-capacity-global.htmlThis University of Sussex study doesn't actually state what the headline implies. In any case, it isn't shown just how this is to support electric power grids, much less all the other power needs. Unfortunately, Mark Jacobson is quoted.
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