Perceptions of nuclear risks

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  • Dave WDave W Shipmate
    Some years (10-15, probably) ago I read an article in an automotive engineering magazine according to which BMW was pooh-poohing vehicles with electric drive trains - they were pushing internal combustion engines burning hydrogen - but it looks like they only made 100 of them back in 2005-7.
  • There are a number of hydrogen-fuelled buses around - and now an experimental train.
  • @Merry Vole, please don't regret your comment. Please keep them commenting as vigorously as rhetorically and as informedly as you have! And well done for your persistence; I've all but suggested XR will take the next step, because I don't think they will for the reasons given. They're not that coherently radicalized. Unabomber type lone wolf, mad dog or Weathermen group type attacks may come if the propaganda continues terrorizing the young, as it did me 50 years ago. But in those 50 years there have been no terrorist murders by extremist environmentalists per se. Ecotage per se has had no significant impact on the global economy.
  • KarlLBKarlLB Shipmate
    KarlLB wrote: »
    Hydrogen fuel is produced from methane, with carbon dioxide as a side product. It gains over burning methane by concentrating the CO2 in one place where it can be more readily sidelined into other industrial processes. You still need the gas wells, and probably fracking and all the other associated technology, to provide that methane which makes it a fossil fuel.

    There are already battery powered tractors available. Not the big tractors used on western commercial monoculture farms, but smaller organic mixed-produce farms don't need tractors of that size.

    In fairness you could get hydrogen from electrolysis of water, but if you manage to make that energy efficient and cost effective you've solved the storage problem and wind and solar can provide all our energy needs.

    Well quite - it's really just a way of storing energy - the energy from burning hydrogen is the energy you put in to electrolyse it in the first place.

    You'd normally use a fuel cell to convert back to electricity, I think, rather than burning hydrogen.

    Same reaction though.
  • Martin54Martin54 Shipmate
    edited October 2020
    @Merry Vole... Please keep them coming...
  • There are a number of hydrogen-fuelled buses around - and now an experimental train.

    Great! All the more reason for an order of magnitude more fission power in the developed world and any at all elsewhere, Iran included. Nothing like it for making cultures grown up.
  • A hydrogen fuelled transport system doesn't need a baseload generating capacity, it's ideally suited to generating capacity based around renewables. Generating hydrogen can follow capacity output - if the wind blows and there's more power being generated than needed elsewhere you increase hydrogen generation, if it's not as windy and the rest of the economy is needing more electricity then you decrease hydrogen generation.
  • OK Sensei, why would you bother with low density energy renewables? Where's the economic sense in that? Including the economic sense in the environmental impact in fertile land use, bird, bat and insect slaughter, energy storage, carbon sequestration and gas backup? Even in a mature economy? As the world needs all the electricity it can get, does it make economic sense to generate the hydrogen with renewables alongside maximizing fission power, let alone replacing it?
  • Why bother? well, the numbers make sense.

    Current global energy use is approaching 175000 TWh per year (of which about 15% is electricity). Let's assume we replace all that with electricity in some form or other (eg: through using that power to produce hydrogen).

    Let's assume we're building 10MW wind turbines (currently off shore turbines are about 12-15MW). Assuming about 30% of installed capacity, that's about 25000 MWh per year. To generate enough power for the whole world we'd need 7m such turbines (to account for increases in energy use, let's call it 10m).

    If each turbine occupies about 0.5 km² that would need an area of about 5m km² about 1% of the earths surface.

  • If each turbine occupies about 0.5 km² that would need an area of about 5m km² about 1% of the earths surface.

    And of course that's a massive overestimate in terms of land usage as the land around turbines is still usable, much of it already grazing land.

    As for @Martin54 's repeated assertion of bird, bat and insect destruction, there is little evidence of that. There are some areas where birds would be particularly vulnerable but there is such an abundance of viable wind power sites it's not beyond the wit of man or woman to choose safer ones.
  • Why bother? well, the numbers make sense.

    Current global energy use is approaching 175000 TWh per year (of which about 15% is electricity). Let's assume we replace all that with electricity in some form or other (eg: through using that power to produce hydrogen).

    Let's assume we're building 10MW wind turbines (currently off shore turbines are about 12-15MW). Assuming about 30% of installed capacity, that's about 25000 MWh per year. To generate enough power for the whole world we'd need 7m such turbines (to account for increases in energy use, let's call it 10m).

    If each turbine occupies about 0.5 km² that would need an area of about 5m km² about 1% of the earths surface.

    I'm being insufferably and ineluctably, incurably dim here I'm sure. No really. I just don't get it. We need to double energy consumption to bring 10 billion people up to our level and more. There are a third of a million wind turbines in the world. We need 30 x as many plus all the storage of which there is none. None. Another 1% for whatever that will be. Plus all the backup from rapidly depleting fossil gas (unless we frack and convert coal). Unless it has to be bio. Another 1%. When is Nigeria going to get to our level then, whenever that is, with this strategy? And India and China and Indonesia and Russia and Pakistan and Iran and Mexico and Turkey and Brazil and Congo and?

    Why not maximize nuclear and big hydro regardless as rapidly as possible?
  • Martin54 wrote: »

    Why not maximize nuclear and big hydro regardless as rapidly as possible?

    Because wind is cheaper, doesn't require complex maintenance, doesn't produce waste that needs to be stored for 10s of thousands of years, can be deployed rapidly rather than taking decades to construct and even more decades to decommission, can be deployed before a full grid system exists in a country, and if it fails you get a small fire and some flying debris at worst. Rapid expansion of nuclear and trying to do it cheaply means accidents, corners being cut and the potential for another disaster or 10.
  • Martin54Martin54 Shipmate
    edited October 2020

    If each turbine occupies about 0.5 km² that would need an area of about 5m km² about 1% of the earths surface.

    And of course that's a massive overestimate in terms of land usage as the land around turbines is still usable, much of it already grazing land.

    As for @Martin54 's repeated assertion of bird, bat and insect destruction, there is little evidence of that. There are some areas where birds would be particularly vulnerable but there is such an abundance of viable wind power sites it's not beyond the wit of man or woman to choose safer ones.

    'less than 1 acre per megawatt is disturbed permanently', 640 acres per square mile, global capacity to last year 651 GW: just doing OOM leads to a thousand square miles taken out of production globally.

    That's the impact now. On arable land. You can't use tractors and combines. To get the world to our level we need 400 PWh per year. I guessed that prior to the following fag packet:

    1 W average = 8.76 kWh per year (365 × 24 Wh per year)

    UK per capita 4K W ~ 40 kWh per year (US, Canada over 2 x that)

    (40,000)

    World population by 2100 reasonably rounded, 10 Bn

    (10,000,000,000)

    Will need 400 PWh per year.

    (400,000,000,000,000)

    So my fag packet agrees with my finger in the air.

    That's 400 000 000 MWh per year which means 400 000 000 acres = 625,000 square miles = 1.6 million square kilometres.

    Typical capacity factors are 15–50% Call it 33%. Scotland and Germany are less than 25.

    So we'd need three times that.

    About 5 million square kilometres.

    We agree Alan!

    There's no quantifiable overestimate in that whatsoever. Let alone a massive one.
    Martin54 wrote: »

    Why not maximize nuclear and big hydro regardless as rapidly as possible?

    Because wind is cheaper, doesn't require complex maintenance, doesn't produce waste that needs to be stored for 10s of thousands of years, can be deployed rapidly rather than taking decades to construct and even more decades to decommission, can be deployed before a full grid system exists in a country, and if it fails you get a small fire and some flying debris at worst. Rapid expansion of nuclear and trying to do it cheaply means accidents, corners being cut and the potential for another disaster or 10.

    I'm working on my bald assertions, which come from science. Do the same.

    Air fauna stats to follow.
  • Martin54 wrote: »

    If each turbine occupies about 0.5 km² that would need an area of about 5m km² about 1% of the earths surface.

    And of course that's a massive overestimate in terms of land usage as the land around turbines is still usable, much of it already grazing land.

    As for @Martin54 's repeated assertion of bird, bat and insect destruction, there is little evidence of that. There are some areas where birds would be particularly vulnerable but there is such an abundance of viable wind power sites it's not beyond the wit of man or woman to choose safer ones.

    'less than 1 acre per megawatt is disturbed permanently', 640 acres per square mile, global capacity to last year 651 GW: just doing OOM leads to a thousand square miles taken out of production globally.

    That's the impact now. On arable land. You can't use tractors and combines. To get the world to our level we need 400 PWh per year. I guessed that prior to the following fag packet:

    1 W average = 8.76 kWh per year (365 × 24 Wh per year)

    UK per capita 4K W ~ 40 kWh per year (US, Canada over 2 x that)

    (40,000)

    World population by 2100 reasonably rounded, 10 Bn

    (10,000,000,000)

    Will need 400 PWh per year.

    (400,000,000,000,000)

    So my fag packet agrees with my finger in the air.

    That's 400 000 000 MWh per year which means 400 000 000 acres = 625,000 square miles = 1.6 million square kilometres.

    Typical capacity factors are 15–50% Call it 33%. Scotland and Germany are less than 25.

    So we'd need three times that.

    About 5 million square kilometres.

    We agree Alan!

    There's no quantifiable overestimate in that whatsoever. Let alone a massive one.

    Let's clarify these numbers. You're saying global consumption will rise to the current UK average, I could argue with that assumption but let's take it for now. 4kW means a 5MW turbine at 30% capacity (Scotland is actually 31%, despite your claim) services 375 people. That means for a 10 billion population you need around 27 million turbines. Now, I don't buy for a minute that a 5MW turbine occupies 5 acres of land (the data you cite is 7 years old and based on legacy stock much smaller than new installations) but, again, let's roll with it. I still end up with a factor of 9 less than you.

    You also keep asserting that turbines would be built on arable land, which there is no reason to believe, and there is no reason you wouldn't be able to utilise the ground around them even if it were arable land.

    Plus, it's all very well bandying these huge figures around, but have you considered that your plan relies on building around 42 000 Hinkley Point Cs? And fuelling them. And keeping them safe. Currently there are fewer than 500 civilian nuclear power plants worldwide. Which do you think is going to be easier to scale safely?
  • Martin54 wrote: »
    @Merry Vole... Please keep them coming...

    No worries @Martin54 , I'm learning so much from the Ship -including from my fellow Groovejet fan :wink:
  • Plus, it's all very well bandying these huge figures around, but have you considered that your plan relies on building around 42 000 Hinkley Point Cs? And fuelling them. And keeping them safe. Currently there are fewer than 500 civilian nuclear power plants worldwide. Which do you think is going to be easier to scale safely?

    I'll compare and contrast 'the math' prior later.

    As for yours (and why shouldn't Nigeria use as much per capita as we?)


    Power output = energy / time

    1 terawatt hour per year = 1×1012 Wh / (365 days × 24 hours per day) ≈ 114 million watts,

    equivalent to approximately 114 megawatts of constant power output, the factor being the 8.76 k below.


    400 PWh per year / ( (3.2 GW x (1 W average = ) 8.76 kWh per year (365 × 24 Wh per year) ) = ) 28 PWh = 14

    The world only needs fourteen Hinkley Point Cs... which is nonsense, not three thousand times that...

    What am I missing Alan?


    But there's no question that nuclear wins hands down on safety, even with a Fukushima a year. A Three Mile Island a year would be pushing it. Show your workings and sources and I'll show mine.

    Show your latest figures for Scotland. I had 24, the average of 2008-10, but used 33 which exceeds your 31.
  • The nominal output of Hinkley C is 3.2GWe, which will generate about 22TWh/y (assuming an approx. 80-90% load factor, the reactors will be shut down for at least 10% of the time, and in shut down will consume a lot of power to keep the pumps going)

    My calculation earlier for total global energy use was 175000 TWh/y (which is a fair bit above current use, to allow for some increases) - divide those numbers and you get about 8,000 Hinkley C's to provide the current global energy usage. How much above that for projected energy use is going to depend on how much more energy use you're going to account for - currently that's increasing by about 4% per annum, much higher in developing nations, whereas in developed nations our energy use is falling (though, part of that could be related to 'outsourcing' our energy use with energy costs in manufacturing now being counted elsewhere).
  • Nigeria won't reach our consumption levels as they can use more efficient technologies and don't have the legacy of older technologies with their high energy consumption. The UK has a lot of existing infrastructure that could be made more efficient. Nigeria also doesn't need heating to anything like the extent of the UK.

    As for my working, I have now spotted an error in mine:
    0.3 × 5000kW/turbine ÷ 4kW/person = 375 people/turbine
    10 billion people ÷ 375 people/turbine = 26.7 million turbines (3 s.f.)
    However, 3200MW ÷ (0.3 × 5MW) = 1920 turbines per nuclear plant rather than 640, so "only" 14 000 nuclear plants (26.7 million ÷ 1920).
  • Nigeria won't reach our consumption levels as they can use more efficient technologies and don't have the legacy of older technologies with their high energy consumption. The UK has a lot of existing infrastructure that could be made more efficient. Nigeria also doesn't need heating to anything like the extent of the UK.

    As for my working, I have now spotted an error in mine:
    0.3 × 5000kW/turbine ÷ 4kW/person = 375 people/turbine
    10 billion people ÷ 375 people/turbine = 26.7 million turbines (3 s.f.)
    However, 3200MW ÷ (0.3 × 5MW) = 1920 turbines per nuclear plant rather than 640, so "only" 14 000 nuclear plants (26.7 million ÷ 1920).

    You lost me mate. 1920 turbines per nuclear plant?

    I see a major error in mine:

    1 W average = 8.7[7] kWh per year (365[.25] × 24 Wh per year) [a factor of 8770, OOM ten thousand, missing in my PWh figures too]

    UK per capita 4K W ~ 40,000 kWh per year (US, Canada over 2 x that) [not ten!]

    4kW = 35 (40 rounded) MWh per year... per Brit. But round down for efficiencies eh? 30 MWh per year by 2100

    x 9 (10 rounded) billion world pop. by 2100 = 270 billion MWh per year

    270 000 000 000 000 000 Wh per year

    270 PWh not far from my 400 PWh... except for the three missing zeroes in me petawatts...

    1 terawatt hour per year = 1×10^12 Wh / (365 days × 24 hours per day) ≈ 114 million watts

    1 000 000 000 000 / 114 000 000 = 8770

    leads to 0.03 PW, 30 TW, 30,000 GW, / 4000 W = 7.5 billion people, 9 billion with efficiencies.

    30,000 GWe / 3.2 GWe Hinkley C = 9000 Hinkley Cs which ballpark agrees with the blessed @Alan Cresswell AND yourself @Arethosemyfeet.

    What factors do more efficient technologies from scratch avail? And upgrading our infrastructure (how?) will avail us what? Nigeria will need air con and refrigeration that at least matches our heating per capita. Hotter, rich small countries use at least 2 to 6 x more than we.

    The rhetorical tennis continues. I owe you air fauna stats.
  • Leorning CnihtLeorning Cniht Shipmate
    edited October 2020
    Nigeria also doesn't need heating to anything like the extent of the UK.

    AFAIK, the cooling needs of hot countries quite considerably exceed the heating needs of cold ones.

    The UK is fortunate in that, with its temperate climate, a well-insulated building needs scarcely anything in the way of heating or cooling at all. Most countries are worse off than the UK in that regard.
  • Nigeria also doesn't need heating to anything like the extent of the UK.

    AFAIK, the cooling needs of hot countries quite considerably exceed the heating needs of cold ones.

    The UK is fortunate in that, with its temperate climate, a well-insulated building needs scarcely anything in the way of heating or cooling at all. Most countries are worse off than the UK in that regard.

    My point ickzackly. But wait! The global average temperature is inexorably rising to at least 2 degrees above pre-industrialization, by 2100, so we're going to need the air con too.

    Nuke it baby, nuke it.
  • Martin54Martin54 Shipmate
    edited October 2020
    Today the PM claimed:

    "Offshore wind farms will generate enough electricity to power every home in the UK within a decade, Boris Johnson has pledged.

    Speaking to the Conservative party conference, the PM announced £160m to upgrade ports and factories for building turbines to help the country "build back greener".

    The plan aims to create 2,000 jobs in construction and support 60,000 more.

    He said the UK would become "the world leader in clean wind energy".

    "Your kettle, your washing machine, your cooker, your heating, your plug-in electric vehicle - the whole lot of them will get their juice cleanly and without guilt from the breezes that blow around these islands," he said."

    "Mr Johnson said the government was raising its target for offshore wind power capacity by 2030 from 30 gigawatts to 40 gigawatts."

    2 years ago it was 22. So we've gained 8 in 2 years? Or rather 6 in the last after 2 in the previous? Another 10 in 10 isn't that impressive. Hang on, 'Wind power delivers a growing fraction of the energy in the United Kingdom and at the beginning of November 2018, wind power in the United Kingdom consisted of nearly 10,000 wind turbines with a total installed capacity of just over 20 gigawatts: 12,254 megawatts of onshore capacity and 7,897 megawatts of offshore capacity.' So in 2 years offshore has gone from 12 to 30? Wow! OK so going from 30 to 40 in 10 is EZPZ. Slouching in fact.

    (In a Matt Dawson BoJo voice) And with a capacity factor of a third, for there to be no gas required, we'll need, oooooh 'Energy use in the United Kingdom stood at 2,249 TWh ... in 2014.' which is 256 GWe, of which 49+/- GWe is domestic gas and electricity and only 12 of that is electricity and we only need 36 capacity to generate that, why, we're actually nearly there!

    We'd need 150 GWe from wind, ten times as much, without gas backup, to fully power all UK homes.

    Aren't we all driving fully electric cars then too? Marvellous!
  • Martin54Martin54 Shipmate
    edited October 2020
    Domestic transport uses 440,000 MWh. 440 GWh. Per year. 50 MW flat out. x 3 = 150 MW. Only 10 offshore turbines needed! To run all of Britain's 33 million cars!! (Imagine Matt Dawson wobbling his jowls.)

    UK Gov. figures 2017 37,524 MTOE x 11.63 = 436,406 MWh/yr, /8766 (365.25 x 24) = 50 MW rounded. And offshore turbines will provide 15 MW. A third of the time. Well never actually, but you know what I mean.

    Can't be right!
  • Our PM IS known for being a wind-bag....
  • Merry Vole wrote: »
    Our PM IS known for being a wind-bag....

    Perfect. We can use him to power the turbines during lulls in the meteorological supply of fast-moving air then.
  • Martin54 wrote: »
    Domestic transport uses 440,000 MWh. 440 GWh. Per year. 50 MW flat out. x 3 = 150 MW. Only 10 offshore turbines needed! To run all of Britain's 33 million cars!! (Imagine Matt Dawson wobbling his jowls.)

    UK Gov. figures 2017 37,524 MTOE x 11.63 = 436,406 MWh/yr, /8766 (365.25 x 24) = 50 MW rounded. And offshore turbines will provide 15 MW. A third of the time. Well never actually, but you know what I mean.

    Can't be right!
    The 2019 UK gov figures are here (pdf), a total of 143MTOE (1700 TWh, approx. 1% of global total)- about 55MTOE (640 TWh) for transport, and 40MTOE (470TWh) for domestic use. 40GW installed capacity will produce about 100TWh ... so about 1/4 of domestic energy use.
  • Thanks Alan, I'm using the same sources and believe it or not, they're wrong! As was I of course... always missing those three orders of magnitude. As were they! At least I'm consistently stupid.

    National Statistics . Energy consumption in the UK . ECUK: Consumption data tables . Table 7 uses MTOE, all the other 18 use KTOE. I've emailed the author.

    It's one of the Accompanying Tables in your link.

    From Table 7, Transport energy consumption allocated to domestic, industrial and service sectors (1990-2017), 2017, Domestic KTOE = 37,524

    38 MTOE

    1 toe = 11.63 megawatt-hours (MWh)

    gives 436,406 GWh/yr

    436 TWh/yr (which compares with your 640 for 2019)

    / 8766 (hrs per year) = 50 GW

    which is in the ballpark of your 40 GW.

    I defer of course.

    8,000 15 MW offshore turbines with 33% capacity.

    Call it 10,000 rounded to power all UK domestic transport by electricity without gas backup and with perfect storage. A quarter of what will be needed for all the energy Johnson is talking about.

    Equivalent to our existing turbine stock and assuming parity of energy use whether by ICE or battery. All in the next 10 years.

    A valid fag packet?
  • 33% for offshore is likely a substantial underestimate. Capacity factors for existing offshore farms here:
    https://energynumbers.info/uk-offshore-wind-capacity-factors
    The lifetime capacity factor for existing stock is over 38%, and last year exceeded 40%. As floating turbines become more common we should expect that to rise. Note also that the siting of many of these farms doesn't expose them to the open Atlantic winds on Scotland's west coast that provide better capacity factors. The load duration curve for the Hywind floating turbine farm is particularly interesting, recording above 90% capacity 30% of the time. The average annual capacity factor has crept up almost 10% since 2006. Both the technology of the turbines themselves and the ability to site them in the best locations have been and are continuing to improve.
  • Sigh. We'll need to quadruple what we have at least in ten years. And create storage for about half the energy (China loses that)? Call it a third. Of your petawatt hour per year? 4 GW?

    Nuke it.
  • Martin54 wrote: »
    Sigh. We'll need to quadruple what we have at least in ten years. And create storage for about half the energy (China loses that)? Call it a third. Of your petawatt hour per year? 4 GW?

    Nuke it.

    Remind me, how much nuclear capacity has been brought online in the UK in the last decade? How much wind? Which one is costing more?
  • Martin54Martin54 Shipmate
    edited October 2020
    You tell me. And what has that got to do with my fag packet? It would be typically British to go for a Heath-Robinson solution. Quaint. While the rest of the world nukes it. I laughed till the tears ran down my trouser leg, my wife too at Johnson last night. Saudi the oil capital of the world. Britain the wind capital. Fart power.

    Nuke it.
  • Martin54Martin54 Shipmate
    edited October 2020
    33% for offshore is likely a substantial underestimate. Capacity factors for existing offshore farms here:
    https://energynumbers.info/uk-offshore-wind-capacity-factors
    The lifetime capacity factor for existing stock is over 38%, and last year exceeded 40%. As floating turbines become more common we should expect that to rise. Note also that the siting of many of these farms doesn't expose them to the open Atlantic winds on Scotland's west coast that provide better capacity factors. The load duration curve for the Hywind floating turbine farm is particularly interesting, recording above 90% capacity 30% of the time. The average annual capacity factor has crept up almost 10% since 2006. Both the technology of the turbines themselves and the ability to site them in the best locations have been and are continuing to improve.

    Isn't that 27%? So, we'd only need twice as many as we need best case. The 4 GW storage? Where's that going to be?

    Nuke it.
  • Martin54 wrote: »
    33% for offshore is likely a substantial underestimate. Capacity factors for existing offshore farms here:
    https://energynumbers.info/uk-offshore-wind-capacity-factors
    The lifetime capacity factor for existing stock is over 38%, and last year exceeded 40%. As floating turbines become more common we should expect that to rise. Note also that the siting of many of these farms doesn't expose them to the open Atlantic winds on Scotland's west coast that provide better capacity factors. The load duration curve for the Hywind floating turbine farm is particularly interesting, recording above 90% capacity 30% of the time. The average annual capacity factor has crept up almost 10% since 2006. Both the technology of the turbines themselves and the ability to site them in the best locations have been and are continuing to improve.

    Isn't that 27%? So, we'd only need twice as many as we need best case. The 4 GW storage? Where's that going to be?

    Nuke it.

    Your 27% ignores that it operates at capacity below 90% the other 70% of the time, raising the overall capacity factor for the site to 55%

    4GW storage? We already have 2.8GW in pumped hydro storage. Another 1.2GW between expansion of that (already planned at Cruachan), battery storage (100MW units already exist), flywheels et al should not present a major problem. The bigger question is not peak load but capacity. 4GW is no good if it only lasts 15 minutes.
  • Even at 100% capacity, 40GW of off shore wind generates 350TWh per year ... cf: domestic use of >450TWh/y. And, the government claims that 40GW will power all the homes in the country. Either I'm missing something, or even with a following wind (almost literally) that 40GW off shore capacity will be a significant short fall compared to the amount we currently use to power our homes. Is this a fictitious number the PM has plucked from the air like £350m? The answer, my friend, is blowing in the wind.
  • Martin54 wrote: »
    33% for offshore is likely a substantial underestimate. Capacity factors for existing offshore farms here:
    https://energynumbers.info/uk-offshore-wind-capacity-factors
    The lifetime capacity factor for existing stock is over 38%, and last year exceeded 40%. As floating turbines become more common we should expect that to rise. Note also that the siting of many of these farms doesn't expose them to the open Atlantic winds on Scotland's west coast that provide better capacity factors. The load duration curve for the Hywind floating turbine farm is particularly interesting, recording above 90% capacity 30% of the time. The average annual capacity factor has crept up almost 10% since 2006. Both the technology of the turbines themselves and the ability to site them in the best locations have been and are continuing to improve.

    Isn't that 27%? So, we'd only need twice as many as we need best case. The 4 GW storage? Where's that going to be?

    Nuke it.

    Your 27% ignores that it operates at capacity below 90% the other 70% of the time, raising the overall capacity factor for the site to 55%

    4GW storage? We already have 2.8GW in pumped hydro storage. Another 1.2GW between expansion of that (already planned at Cruachan), battery storage (100MW units already exist), flywheels et al should not present a major problem. The bigger question is not peak load but capacity. 4GW is no good if it only lasts 15 minutes.

    I didn't ignore it at all. Hence my 'half'. And aye, it needs to last 45% of the time by your best estimates?
  • Martin54Martin54 Shipmate
    edited October 2020
    Even at 100% capacity, 40GW of off shore wind generates 350TWh per year ... cf: domestic use of >450TWh/y. And, the government claims that 40GW will power all the homes in the country. Either I'm missing something, or even with a following wind (almost literally) that 40GW off shore capacity will be a significant short fall compared to the amount we currently use to power our homes. Is this a fictitious number the PM has plucked from the air like £350m? The answer, my friend, is blowing in the wind.

    : ) made my wife laugh too! And she's a green eyed non-evidence based optimist like allllll our friends. The con will work and guarantee him another 5 years as tut North will be building windmills. No need for a Robin Hood tax! Huzzah!
  • Martin54 wrote: »
    Martin54 wrote: »
    33% for offshore is likely a substantial underestimate. Capacity factors for existing offshore farms here:
    https://energynumbers.info/uk-offshore-wind-capacity-factors
    The lifetime capacity factor for existing stock is over 38%, and last year exceeded 40%. As floating turbines become more common we should expect that to rise. Note also that the siting of many of these farms doesn't expose them to the open Atlantic winds on Scotland's west coast that provide better capacity factors. The load duration curve for the Hywind floating turbine farm is particularly interesting, recording above 90% capacity 30% of the time. The average annual capacity factor has crept up almost 10% since 2006. Both the technology of the turbines themselves and the ability to site them in the best locations have been and are continuing to improve.

    Isn't that 27%? So, we'd only need twice as many as we need best case. The 4 GW storage? Where's that going to be?

    Nuke it.

    Your 27% ignores that it operates at capacity below 90% the other 70% of the time, raising the overall capacity factor for the site to 55%

    4GW storage? We already have 2.8GW in pumped hydro storage. Another 1.2GW between expansion of that (already planned at Cruachan), battery storage (100MW units already exist), flywheels et al should not present a major problem. The bigger question is not peak load but capacity. 4GW is no good if it only lasts 15 minutes.

    I didn't ignore it at all. Hence my 'half'. And aye, it needs to last 45% of the time by your best estimates?

    That's... not how it works. At all. The capacity factor gives you an idea of how much extra capacity you need in total assuming you can freely redistribute that energy in time. Clearly without sufficient storage capacity you can't do that. However, a 40% capacity factor doesn't mean you need storage to cover the other 60%, the modelling of how much storage you need is way more complex than that, depending on the energy mix, peak demand, how much demand can be managed down, how big a grid you're working with (e.g. can you import solar energy from southern Europe when it's still and cloudy here?). Even a fully nuclear grid needs storage, because it's massively problematic to keep turning nuclear plants on and off. The French grid frequently needs to dump electricity because it can't adjust to demand very quickly, and as such is the largest exporter of electricity in the world. It relies on its neighbours to be able to store electricity or adjust their own supply rapidly to compensate.
  • Martin54Martin54 Shipmate
    edited October 2020
    Martin54 wrote: »
    Martin54 wrote: »
    33% for offshore is likely a substantial underestimate. Capacity factors for existing offshore farms here:
    https://energynumbers.info/uk-offshore-wind-capacity-factors
    The lifetime capacity factor for existing stock is over 38%, and last year exceeded 40%. As floating turbines become more common we should expect that to rise. Note also that the siting of many of these farms doesn't expose them to the open Atlantic winds on Scotland's west coast that provide better capacity factors. The load duration curve for the Hywind floating turbine farm is particularly interesting, recording above 90% capacity 30% of the time. The average annual capacity factor has crept up almost 10% since 2006. Both the technology of the turbines themselves and the ability to site them in the best locations have been and are continuing to improve.

    Isn't that 27%? So, we'd only need twice as many as we need best case. The 4 GW storage? Where's that going to be?

    Nuke it.

    Your 27% ignores that it operates at capacity below 90% the other 70% of the time, raising the overall capacity factor for the site to 55%

    4GW storage? We already have 2.8GW in pumped hydro storage. Another 1.2GW between expansion of that (already planned at Cruachan), battery storage (100MW units already exist), flywheels et al should not present a major problem. The bigger question is not peak load but capacity. 4GW is no good if it only lasts 15 minutes.

    I didn't ignore it at all. Hence my 'half'. And aye, it needs to last 45% of the time by your best estimates?

    That's... not how it works. At all. The capacity factor gives you an idea of how much extra capacity you need in total assuming you can freely redistribute that energy in time. Clearly without sufficient storage capacity you can't do that. However, a 40% capacity factor doesn't mean you need storage to cover the other 60%, the modelling of how much storage you need is way more complex than that, depending on the energy mix, peak demand, how much demand can be managed down, how big a grid you're working with (e.g. can you import solar energy from southern Europe when it's still and cloudy here?). Even a fully nuclear grid needs storage, because it's massively problematic to keep turning nuclear plants on and off. The French grid frequently needs to dump electricity because it can't adjust to demand very quickly, and as such is the largest exporter of electricity in the world. It relies on its neighbours to be able to store electricity or adjust their own supply rapidly to compensate.

    Believe it or not I know that too. That it's complex. Hence my ? So what's the ball park? If we need to build enough so the 55% offshore fulfils our 1 PW needs, how much storage do we need? 0.1%?

    Nuke it.
  • Complex? A bit certainly, but it's not nuclear physics complex. We have a pretty good idea of our average energy consumption. You need average power generation to be slightly more than that (because there will be some losses in whatever storage method you have to even out the fluctuations). That's the simple part.

    It gets more complex because demand is variable, and can change very rapidly (the classic of all the kettles in the country going on when the half time whistle blows at the world cup final). Supply is also variable, but usually without very rapid shifts (exceptions would be unscheduled shutdowns of large generating capacity, eg: an emergency scram at a nuclear station). Wind or solar power is also predictably variable, weather forecasts can be very effective at identifying when these will be higher or lower than average over a few days. Generally variations in generator output even out to a considerable extent over large networks - a single wind generator can change output between 0 and 100% over a couple of days as weather systems change, but the total power output for an array of wind turbines across a large geographical area will vary over a smaller range and the larger the geographical area the smaller that variation in total output (there can be issues with heavy reliance on solar which, obviously, drops to zero at night across very large areas).

    There are several options to deal with these variations in output and demand, and the optimal solution will almost certainly include a combination of these.

    1. Demand management. Not all uses of electrical power are time critical, and there are some where use can be readily varied to even out demand variations and/or match supply variations. An example could be pumping water to reservoirs for gravity feed to homes (something that makes Scottish Water the largest single electricity user in Scotland), as long as the reservoirs are kept at a suitable level it doesn't much matter when the water is pumped into them so can be shut down when demand exceeds supply or more water pumped when supply exceeds demand. Production of hydrogen to fuel cleaner vehicles could be another example.

    2. Ancillary power production. Have some additional generators that can be switched on and off rapidly to supplement supply shortfalls or demand spikes. At a local level this is probably the most effective for critical situations - hospitals and the like will already have emergency generator capacity to cope with interruptions to the power supply. As mentioned previously, this is a vital safety feature for nuclear power plants. The UK currently has several gas-fired power stations to fulfil this role nationally.

    3. Storage and buffering. This could be a variant on option 2, because it is effectively an ancillary power system, but I think it's sufficiently different to warrant a separate option. This could be local to the generator (eg: battery backup at a wind farm to level output), it could be discrete remote facilities (eg: pumped storage hydro), it could be dispersed (eg: having a proportion of battery capacity in electric vehicles hooked into charging points dedicated to matching supply and demand). Probably all three to differing extents. Modern (large) wind turbines also act to an extent as their own fly-wheel storage, the mass and associated inertia smooth out short time scale variations in wind strength (over a few hours).
  • DafydDafyd Shipmate
    The big problem with nuclear power is that it is highly inflexible. You do not want to be changing the output of your nuclear power plant suddenly to cope with everyone putting their kettles on. That makes nuclear excellent for covering your base load but for variations in power you ideally need something else.

    The other problem as I understand, it is that the kind of uranium that is plentiful is the same kind that makes your neighbours and assorted superpowers nervous if they don't get on with you.
  • Cuh! Fuh! You forget how insufferably, bet a dime Martini, sodding dim I am Alan. Or rather you forgive much.

    What om feelin in me water (in the shower; where my thinking is as good as it gets, prior to reading your last magisterial comment and reinforced by it) is that for the UK wind vs. nuclear comes out faster for wind; it can be implemented a turbine at a time, combined with hydro storage for Scotland to export to Britain. I feel in the same bladder load that nuclear's cheaper (including safer) using full green accounting.

    For the billions in the developing world, with less coast and wind per capita, it's still got to be nuclear. For the big rich regions too: US, Europe, Japan, S. Korea.
  • Nuclear and wind are both very safe, in terms of attributable deaths (which is ahead depends on who does the calculations), but new nuclear capacity is far more expensive.

    The US has thousands of square miles of desert (solar) and massive, windy coasts and hills. Japan is pretty damn coastal and mountainous too. Thing is, once we can float the things in open sea it won't matter who's got more coast, you can string them out to the 200 nm limit and export it inland (not that there are many populous countries without significant coastline.
  • Dafyd wrote: »
    The big problem with nuclear power is that it is highly inflexible. You do not want to be changing the output of your nuclear power plant suddenly to cope with everyone putting their kettles on. That makes nuclear excellent for covering your base load but for variations in power you ideally need something else.

    The other problem as I understand, it is that the kind of uranium that is plentiful is the same kind that makes your neighbours and assorted superpowers nervous if they don't get on with you.

    France seems to manage with 71% nuclear.

    That Pandora's box was opened 75 years ago.
  • Nuclear and wind are both very safe, in terms of attributable deaths (which is ahead depends on who does the calculations), but new nuclear capacity is far more expensive.

    The US has thousands of square miles of desert (solar) and massive, windy coasts and hills. Japan is pretty damn coastal and mountainous too. Thing is, once we can float the things in open sea it won't matter who's got more coast, you can string them out to the 200 nm limit and export it inland (not that there are many populous countries without significant coastline.

    Where is new nuclear far more expensive than wind, over its 60-80-100 year lifecycle with full green accounting? The Bristol Channel? What a political debacle. "According to December 2017 estimates, Hinkley is being built for £20.3bn by 2025, to be paid over a 35 year period. According to Dieter Helm, professor of Energy Policy at the University of Oxford, "Hinkley Point C would have been roughly half the cost if the government had been borrowing the money to build it at 2%, rather than EDF's cost of capital, which was 9%." In September 2019, further costs were identified that bring the estimated total to £22.9bn, and may further delay operations. The involvement of state-owned CGN was also questioned after it was sanctioned by the United States government for espionage."

    Solar is a toxic lie. It smells of Musk. You cannot pave deserts. Should not any way. You should irrigate them including with desalinated sea water using cheap electricity from nuclear. Solar will NEVER happen. Even more never than fusion.

    Funny thing about Japan. Why hasn't it thought of that? Maybe it has... They don't seem to care how much their electricity costs.

    The only argument I can see is that it's incremental 15 MW rated at a time and a mere 400 gets you a Hinkley Point C.
  • You keep referencing "full green accounting" like it's some magic formula to make nuclear look better. I'm struggling to see how including the decommissioning and waste disposal costs are meant to make nuclear look better.
  • Martin54 wrote: »
    Where is new nuclear far more expensive than wind, over its 60-80-100 year lifecycle with full green accounting? The Bristol Channel? What a political debacle. "According to December 2017 estimates, Hinkley is being built for £20.3bn by 2025, to be paid over a 35 year period. According to Dieter Helm, professor of Energy Policy at the University of Oxford, "Hinkley Point C would have been roughly half the cost if the government had been borrowing the money to build it at 2%, rather than EDF's cost of capital, which was 9%." In September 2019, further costs were identified that bring the estimated total to £22.9bn, and may further delay operations.
    A couple of points, but as this relates to finance it's not really my area of expertise.

    1. It doesn't make sense to compare costs with/without government financing when generating companies building wind farms, installing solar panels etc do so by borrowing at market rates rather than being funded by loans at rates the government can borrow at. If a wind farm gets a better rate than the 9% EDF are paying then that would reflect building windfarms is much lower financial risk than nuclear.

    2. The only way that Hinkley C works economically is with the government passing legislation guaranteeing that energy suppliers will buy the electricity at a minimum price significantly more than the price for other generating supplies.

    3. The price being charged reflects the initial investment (to pay off that £23b+ construction cost over 35y), a small amount to cover running costs (there'll be a lot of staff to pay), and then after the loan is paid off they'll need to build up a pot over the rest of the lifetime of the reactor to pay for decommissioning and waste disposal - and, as the method for disposing of spent fuel has not yet been determined how much that will cost is a wild guess at best (and, almost certainly end up being more than EDF put aside for it, leaving the tax payer to pick up the difference).
  • You keep referencing "full green accounting" like it's some magic formula to make nuclear look better. I'm struggling to see how including the decommissioning and waste disposal costs are meant to make nuclear look better.
    What a "full green accounting" would do is make fossil fuels, including the economic methods of producing hydrogen, look even more awful than they are.
  • Martin54Martin54 Shipmate
    edited October 2020
    Martin54 wrote: »
    Where is new nuclear far more expensive than wind, over its 60-80-100 year lifecycle with full green accounting? The Bristol Channel? What a political debacle. "According to December 2017 estimates, Hinkley is being built for £20.3bn by 2025, to be paid over a 35 year period. According to Dieter Helm, professor of Energy Policy at the University of Oxford, "Hinkley Point C would have been roughly half the cost if the government had been borrowing the money to build it at 2%, rather than EDF's cost of capital, which was 9%." In September 2019, further costs were identified that bring the estimated total to £22.9bn, and may further delay operations.
    A couple of points, but as this relates to finance it's not really my area of expertise.

    1. It doesn't make sense to compare costs with/without government financing when generating companies building wind farms, installing solar panels etc do so by borrowing at market rates rather than being funded by loans at rates the government can borrow at. If a wind farm gets a better rate than the 9% EDF are paying then that would reflect building windfarms is much lower financial risk than nuclear.

    2. The only way that Hinkley C works economically is with the government passing legislation guaranteeing that energy suppliers will buy the electricity at a minimum price significantly more than the price for other generating supplies.

    3. The price being charged reflects the initial investment (to pay off that £23b+ construction cost over 35y), a small amount to cover running costs (there'll be a lot of staff to pay), and then after the loan is paid off they'll need to build up a pot over the rest of the lifetime of the reactor to pay for decommissioning and waste disposal - and, as the method for disposing of spent fuel has not yet been determined how much that will cost is a wild guess at best (and, almost certainly end up being more than EDF put aside for it, leaving the tax payer to pick up the difference).

    You on a bad day are to be preferred over anyone else's good, he said sycophantically.

    I take your point about the level playing field.

    What does S. Korea do? I.e. are their any models of fair financing where nuclear is still the rational green option. I would posit that it always is regardless of waste (what's the Marianas Trench for?; ) and decommissioning. On site. Although I AM being persuaded that due to the 15MW incremental rollout of 55% capacity wind for two hundred miles out to sea, we can run the world by 2100. But that looks like a technofix - a NON-existent technology in terms of scale, sustainability and environmental impact - nearly as bad as solar, the worst of them all. OK, OK, not that bad, wind that is. Scaling up nuclear & big hydro for the world looks an OOM more feasible than big wind.
  • Dafyd wrote: »
    The other problem as I understand, it is that the kind of uranium that is plentiful is the same kind that makes your neighbours and assorted superpowers nervous if they don't get on with you.

    Naturally occurring Uranium is mostly (99.3%) U-238. U-238 isn't fissile, although it does undergo fission when bombarded with fast neutrons, and will produce Pu-239 by capturing a neutron followed by a couple of beta decays. Pu-239 is the most popular choice for a nuclear weapon.

    U-235 is the useful Uranium isotope both for fission power and for weapons, but it's about 0.7% of naturally occurring uranium. Little Boy - the gun-type bomb dropped on Hiroshima - was a U-235 device. It was a guaranteed explosion, but you have do to a lot of isotope separation to produce a U-235 enriched enough sample in order to explode. That's why Fat Man (the Nagasaki bomb) and the several backups waiting in the wings were all Plutonium devices - it took too long to produce enough weapons-grade Uranium*, whereas chemical purification of plutonium is relatively simple. The risk was that Plutonium bombs have to be implosion rather than gun-type devices, which have much more scope for a small error leading to a failed detonation.

    That's why Little Boy was dropped first - psychologically, the first bomb had to be guaranteed to work.


    *Reactors for nuclear power production need enriched fuel, but only need something like 4-5% U-235. Weapons require somewhere in the 90% ballpark, which is more challenging and time-consuming.

    If I'm lucky, Dr. Cresswell might give this summary a B-. I've glossed over several details.
  • Martin54Martin54 Shipmate
    edited October 2020
    That's why Little Boy was dropped first - psychologically, the first bomb had to be guaranteed to work.

    That's fascinating.
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