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Post by David B. Benson on Apr 8, 2020 8:21:58 GMT 9.5
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Post by David B. Benson on Apr 12, 2020 13:05:18 GMT 9.5
I had hoped for more discussion on this thread. However, we have few discussants.
As an "opener", I point out that using wind power appears to lead to an increase in natural gas burners. I understand why this occurs in ERCOT Texas. There natural gas is inexpensive. Somehow the same has occurred in the state of South Australia, where, as far as I know, natural gas must be imported.
Enough for a lead-off.
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Post by Roger Clifton on Apr 12, 2020 18:26:02 GMT 9.5
using wind power appears to lead to an increase in natural gas burners... the same has occurred in the state of South Australia, where, as far as I know, natural gas must be imported. SA has gas. SANTOS is a big gas producer in SA and NT – no surprise there. However the market for gas is decided by international prices, as most Australian gas production is exported as LNG. Contrarily, the SA market for electricity is decided by the politics of wind generation. When the operators of open cycle gas turbines in SA refused to back up wind variation as unprofitable, the pro-wind government of the day was angered enough to make the questionable purchase of "the world's biggest battery". As elsewhere in the world, South Australian fans of wind generation are in shouting denial that most of their energy is generated by the fossil backup. Consequently the same government had to discreetly purchase 250 MW of fossil backup generation. It would have cost more than the battery, but it was needed to provide the power that the battery could not. Thus it provided the autonomy of reserve backup that the battery was loudly touted as providing. The subsequent anti-wind government considered it wasteful to have a generator sitting idle in reserve, so set it working continuously to contribute to baseload. Consequently the backup for the wind shifted (along a fragile interconnector) across the state border into Victoria, forcing an increase of the spinning reserve into the brown coal generation there. Which is pretty well where the story began.
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Post by Roger Clifton on Apr 12, 2020 20:11:50 GMT 9.5
using wind power appears to lead to an increase in natural gas burners. Yes. Intermittency of wind generation requires similarly intermittent gas backup whose inefficiency overwhelms the savings due to the wind generation... Consider a future grid where all capacity to respond to variation is already committed. Then supplying an increase of demand with an increase in wind generation (of 30% capacity factor) requires matching with an equal capacity of responsive open cycle gas turbines (of ~35% efficiency). Thus the generation of 100 MW by the combination will consume - 100*(1.00-.30)/0.35 = 200 MW (t) of gas On the other hand, if the opportunity to use wind is ignored and combined cycle gas turbines (of ~66% efficiency) are used, they will consume – 100*(1.00)/0.66 = 150 MW (t) of gas. Far from reducing gas consumption, the wind generation actually increases it. Changing the efficiency estimates will change those numbers somewhat, but the comparison will almost inevitably confirm that introduction of wind power increases emissions.
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Post by David B. Benson on Apr 14, 2020 4:07:09 GMT 9.5
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Post by David B. Benson on Apr 14, 2020 11:52:18 GMT 9.5
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Post by engineerpoet on Apr 24, 2020 6:20:18 GMT 9.5
Discovered and read: "Costs of Reprocessing Versus Directly Disposing of Spent Nuclear Fuel" www.cbo.gov/sites/default/files/cbofiles/ftpdocs/88xx/doc8808/11-14-nuclearfuel.pdfMoney quote from page 3:$1300/kg sounds like a lot, but based on reprocessing of 10,000 tons/year of driver fuel plus another 5,000 tpy of breeding blanket material (much of which can probably be cycled 2-3 times before reprocessing) to generate 1.3 TW(e), the cost of reprocessing would only be 1.71 mills/kWh(e). It would be closer to 20¢/million BTU thermal; this is about 1/10 the current cost of steam coal. At $1300/kg, recycling 15000 tpy is $19.5 billion per year. Peanuts. We can do this, and we ought to be able to do it for cheap. And we can make the "waste" literally go away.
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Post by Roger Clifton on Apr 26, 2020 17:23:02 GMT 9.5
We can do this, and we ought to be able to do it for cheap. And we can make the "waste" literally go away. The linked report, " Costs of Reprocessing Versus Directly Disposing of Spent Nuclear Fuel" is dated 2007 and compares the costs of uranium-only fuel and mixed-oxide fuel for slow neutron reactors. The 2011 book, " Plentiful Energy" makes a similar analysis for fast neutron reactors and reaches a similar conclusion. In both cases the cost to the consumer of recycling is less than one cent per kilowatt-hour. In a profit driven landscape, bean counting would save that tiny amount and bury the bulky once-used fuel instead. Recycling should appeal to everyone concerned, but it would take legislation requiring recycling and fission of the transuranics elements. The cost gap between once-only and recycled fuel is doomed to widen. The cost of enrichment has been declining stepwise across the decades. Recycling was competitive in the days of energy-expensive gaseous diffusion. It became less attractive when gas centrifuges came in. Imminently, enrichment by laser excitation will make enrichment cheaper still. Further, new techniques for finding and extracting uranium have permanently driven down the cost of raw uranium to the order of $100 per kilogram – an even smaller fraction of a cent per kilowatt-hour. The Chinese forward plans for reactors are to expand their fleet of slow neutron reactors until they are producing about 1 kW per capita by 2050, and then transition to fast neutron reactors after that towards 2100. However the transition date of 2050 seems to be calculated on the basis that the start-up fuel (containing reactor grade plutonium) for the fast reactors has to be produced by recycling the accumulated slow reactor fuel. However, the declining cost of enrichment suggests that the Chinese fleet will have fast reactors before 2050 by using (perhaps ~20% enriched) uranium-only as their start-up fuel.
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Post by engineerpoet on Apr 27, 2020 5:42:44 GMT 9.5
I was thinking of it more as a way to eliminate the perceived problem of HLW, which at a fraction of a cent per kWh would be worth more politically than it would cost fiscally. Being able to use Cs-137 and perhaps Sr-90 to remove pathogens from wastewater or produce shelf-stable meat and milk would be another value-added option.
The 2007 report does not contain the string "pyroprocessing", so it's certain that it over-estimates the cost. But as I said, $1300/kg is a ceiling and is still affordable.
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Post by Roger Clifton on Apr 27, 2020 10:59:56 GMT 9.5
I was thinking of it more as a way to eliminate the perceived problem of HLW Yes, I'm with you there. I feel that we should tidy up after ourselves, even if the bean counting says that it's cheaper to store used fuel indefinitely. To me that's creating waste and labelling it as dirty. If we were to reprocess and recycle, there would only be fission products to bury to the order of one gram per person per year. A tiny quantity, easily buried as deeply as the fearful require. But that's a hypothetical world where we recycle on principle. We need a real world where we recycle because that is the law. When the antis chant off "what about the waste?", I riposte "let's recycle it".
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Post by David B. Benson on Apr 28, 2020 10:53:51 GMT 9.5
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Post by engineerpoet on Apr 28, 2020 20:31:30 GMT 9.5
'Think small, learn fast' might be the way to go for novel energy technologies Pretty much the philosophy of NuScale, no?
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Post by David B. Benson on May 1, 2020 8:47:48 GMT 9.5
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Post by engineerpoet on May 1, 2020 13:38:41 GMT 9.5
Not a word about nuclear power nor grid stability issues. Green hydrogen appears to be the only energy store in this summary of the IRENA report. A $110 trillion effort. Cost of supplying 800 quads of primary energy (heat) using nuclear reactors @$1500/kW(t): almost exactly $40 trillion investment, plus O&M. 800 quads is well above today's primary energy use.
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Post by David B. Benson on May 1, 2020 13:55:33 GMT 9.5
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Post by David B. Benson on May 22, 2020 15:47:20 GMT 9.5
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Post by David B. Benson on May 29, 2020 20:37:29 GMT 9.5
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Post by David B. Benson on May 29, 2020 23:09:50 GMT 9.5
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Post by David B. Benson on Jun 2, 2020 19:56:32 GMT 9.5
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Post by David B. Benson on Jun 2, 2020 23:52:36 GMT 9.5
Assume no more hydropower added, which would be better for the rivers. Available then are, with estimates of future LCOE: Solar PV, $10/MWh @ utility-scale Wind power, $20/MWh Existing coal, $30/MWh Combined cycle gas turbines, $50/MWh Nuclear power plants, $40/MWh and up, maybe less than that in Texas
In addition, utility-scale batteries, $10/MWh plus the cost of charging
These costs are assumed to include the grid surcharge for the ancillary services which keep the grid up and functioning. In any case, in an energy-only market it is the relative prices which matter. For the least price bid is the next dispatched, although everybody that generates receives the top bid for the last required generator.
With these prices, lots of solar PV will be built. The mid-day excess goes to charging batteries for the evening power requirements. If there is even more excess, it costs so little that the hydrogen maker can afford to hydrolyze even maybe sea water. The hydrogen is stored against future need. I believe that hydrogen fuel cells are still very expensive, so imagine the hydrogen is burned in the combined cycle turbines. So the cost of hydrogen has to be less than the cost of natural gas.
Of course, the combined cycle turbines, not running often, needs plenty of $$ when actually running. Somehow ERCOT manages to do something akin to this every summer, but still burning natural gas and coal.
And some nuclear power plants provide baseload power, but only so long as this is less expensive than making and burning hydrogen.
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Post by David B. Benson on Jun 18, 2020 3:55:28 GMT 9.5
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Post by David B. Benson on Jun 20, 2020 7:50:24 GMT 9.5
Analysis Supports Coal-Like Fuel For Power Plants Darell Proctor 2020 Jun 19 Power Magazine www.powermag.com/analysis-supports-coal-like-fuel-for-power-plants/SERF is made out of whatever burns and acts almost like anthracite. Available in two formulations for ex-coal burners and also for Portland cement manufacture. Claimed to cut CO2 emissions to 4/9ths of using coal, although that might be in comparison to bituminous or even sub-bituminous coal grades. The claim is that this keeps coal fired thermal generators in operation to the end-of-life. More interesting is the possibility of reducing CO2 emissions from Portland cement production.
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Post by engineerpoet on Jun 21, 2020 7:35:01 GMT 9.5
The use of the SERF acronym without ever expanding it is irritating (and yes I checked the website). The fuel itself looks a great deal like torrefied biomass.
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Post by David B. Benson on Jun 21, 2020 7:55:03 GMT 9.5
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Post by David B. Benson on Jun 30, 2020 9:48:43 GMT 9.5
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Post by David B. Benson on Jul 2, 2020 12:50:04 GMT 9.5
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Post by David B. Benson on Jul 8, 2020 15:07:37 GMT 9.5
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Post by David B. Benson on Jul 25, 2020 0:17:36 GMT 9.5
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Post by David B. Benson on Aug 5, 2020 16:04:01 GMT 9.5
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Post by David B. Benson on Aug 6, 2020 11:07:56 GMT 9.5
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