13 ms·

Sustainable Energy without the Hot Air (Revised, Community Edition)

168 points by rufuspollock 5y ago

ycomb-uit-co-uk 5y ago
Have a look at http://2050-calculator-tool.decc.gov.uk/ http://2050-calculator-tool.decc.gov.uk/ (I was David's Editor for "Sustainable Energy - without the hot air". There's been quite a bit of interest in updating the book, but there are obvious difficulties. If have suggestions, let me know. Niall Mansfield sewtha-2.0@uit.co.uk )
- lucb1e 5y ago
  I wonder if this is correct. Setting the nuclear slider to max single-handedly reduces emissions by 30%, decreases energy costs rather than increases, does not require land use change, improves air quality, and also reduces electricity demand by using the waste heat for district heating. Now add: (1.) electrification of freight transport, (2.) tackling the (relatively) quick wins in industry electrification, and (3.) carbon capture, and one gets to 75% emissions reduction with less than one percent of cost increase and zero behavioural changes (such as eating less meat or flying less often) are required. I can't find any other combination in this calculator that leaves nature so untouched, requires so little land use, requires no behaviour adjustment, or is so cheap while still reducing emissions meaningfully. (Well, geothermal is nearly as good but then its maximum potential is only a small percentage of energy demand and it's also a bit more expensive per Joule.) Probably the most unrealistic part is public support for the choice, but in a perfect world? Would it be this simple?!
  - johnny53169 5y ago
    > (3.) carbon capture, and one gets to 75% emissions reduction with less than one percent of cost increase Carbon capture and less than one percent cost increase looks suspect to me
    - lucb1e 5y ago
      Agreed. I didn't use it at first because I thought it would be cheaper to just reduce emissions than undo emissions, at least up until this 80% goal that the site poses. Without any carbon capture, you're still at 61% emissions reduction and the cost actually decreases by 0.8% from today rather than increasing by 0.6%. If you get to 61% with the only change being "build nuclear and make use of it" (no lifestyle changes, no cost changes, no landuse changes), that would be amazing. Hence my main question is about the nuclear aspect. The argument against nuclear is usually that it's super scary and dangerous (easy enough to disprove that with numbers, so long as you're not talking to someone from germany) and the fallback argument is that it's so expensive now that PV+wind became so much cheaper. This calculator seems to show the opposite of that latter argument (when looking purely at price).
      - zbrozek 5y ago
        Surely there are studies of LCOE for both when trying to produce baseload capacity. Personally, I suspect nuclear construction costs are dominant, but that should also be addressible through improvements in technology and policy.
  - m4rtink 5y ago
    Not a big surprise given the insanely high power density of nuclear reactors.
  - addicted 5y ago
    This is strange considering nuclear continues to be the most expensive new form of fuel and has only been getting more expensive with every passing decade. There is new research in nuclear which if successful would bring costs down but it’s hard to see how maxing out on nuclear reduces average costs. Edit: I see now. The original data is at least over 5 years old, at which point it’s possible that wind/solar may still have been more expensive than nuclear. Editx2: The original book on which the original site is based was published in 2008/2009. It’s not clear how much of the data on this new site has been updated.
  - sdenton4 5y ago
    See also, peak uranium : https://en.m.wikipedia.org/wiki/Peak_uranium https://en.m.wikipedia.org/wiki/Peak_uranium 2017 known supply is enough for 130 years at current usage (supplying about 10% of global energy). Each doubling of production halves the peak timeline. Basically no one expects discovery to outpace usage. So, at best, nuclear is a stop gap and part of a different long term solution. Which could be fine! But the extremely low LCOE and fast build time for modern renewables suggests that nuclear is simply losing the race for relevance.
    - korantu 5y ago
      Fuel is very small part in cost of nuclear generation; As fuel price start increasing, more sources become viable, including sea water. There is practically unlimited supply once it happens, and this is before accounting for reprocessing. (and reprocessing happens in France, for example)
      - sdenton4 5y ago
        Right, but the fuel cost goes up over time as extraction gets harder (eventually requiring entire new types of facilities, which themselves take a decade to build), even as wind and solar continue their exponentially decreasing LCOE cost curve. The exponentially decreasing cost curve is the part that I think people haven't actually internalized. The arguments on the pro-nuclear side are pretty much the same as they were ten years ago. (right down to 'we'll have thorium in ten years!') But things are very different now: It's like arguing for large scale investment in punch-card sorting machines circe 1960. Yes, the punch-card sorting machines can be used to manage all your bank data, but the digital processing are getting exponentially better with time and have been actually better for a couple years. But the proponents of punch card sorting machines haven't internalized the message yet.
        cnlevy 5y ago
        > Right, but the fuel cost goes up over time as extraction gets harder Uranium demand is declining, there has been almost no Uranium prosection in the last decades; Therefore it's no wonder reserves are diminishing. If demand picks up, prospecting will renew, and a lot more uranium will be discovered. This is not accounting for thorium reserves, which have never been seriously prospected.
- rufuspollock 5y ago
  Thanks Niall - updating the book is exactly what we are hoping to do and still thinking the best form for that. Re that tool i've been in correspondence with one of the other creators re trying to understand the source code etc - see https://github.com/life-itself/climate/issues/2 https://github.com/life-itself/climate/issues/2
- tito 5y ago
  Rufus, terrific work here! Niall - great to see you here. My mind goes towards helping others with "powers of 10 math" about climate. SWITHA for me embodied this concept of "how to think about the climate" more than anything. That type of thinking is needed more now than ever. Even that line "2 billion years of energy reserves", so powerful.
- deleted 5y ago
  [deleted]
algo_trader 5y ago
Alas, this is probably pointless. Some technologies (PV, batteries, wind) have improved by an order of magnitude - and swamp out all other considerations. EDIT: to be clear, i loved the original book, and have re-read it several times over the years.
- bjelkeman-again 5y ago
  David MacKay’s work was for me very important. It showed how one should do a systems analysis for a country to understand how one can achieve the change required. I was astonished when I talked to several of the leading people responsible for energy policy in several political parties in my country, to find they really had no clue about what they where doing on a systems level. I think that updating this book is not pointless, but more importantly doing the same for more countries is really important.
  - phreeza 5y ago
    It would be fantastic to turn the chapters into Templates where one has to plug in the relevant parameters for a country and see the calculations for that country.
    - algo_trader 5y ago
      And multiple PhD students have done so! For example, the Stanford/Jacobson study on powering the world with wind/solar/water. Some results were famously silly, such as filing Finland with solar panels, or adding the cost of nuclear war to nuclear reactors. Jacobson sued other academics then backed down. The point is, 5-10 years on, these models turned out to be over pessimistic! Australia doesn't need fancy modelling - simple roof top solar there is on target to meet full day time demand in 2-3 years. Conversely we still dont really know how to meet the last 5% of outlier energy demand scenarios.
      - selimthegrim 5y ago
        Has Jacobson stopped suing people though
lr1970 5y ago
Sir David Mackay [0] was a great mind who contributed major discoveries in Machine Learning, Information Theory, Coding Theory and Physics. His book "Information Theory, Inference, and Learning Algorithms" is a great resource for anyone learning ML and who wants to understand how ML, Information Theory and Statistics all fit together. The book is available for free download as a pdf [1] as well as for purchase. His untimely death from cancer in 2016 at the age of 48 is a big loss to Science. His book on Climate Change "Sustainable Energy without the Hot Air" (also available as pdf) [2] is a testament to breadth and versatility of his scientific interests. [0] https://en.wikipedia.org/wiki/David_J._C._MacKay https://en.wikipedia.org/wiki/David_J._C._MacKay [1] http://www.inference.org.uk/mackay/itila/book.html http://www.inference.org.uk/mackay/itila/book.html [2] http://www.withouthotair.com/ http://www.withouthotair.com/ EDIT: typos
- femto 5y ago
  Here's the download link for the Without Hot Air book: http://www.withouthotair.com/download.html http://www.withouthotair.com/download.html The parent's link was for his other book "Information Theory, Inference, and Learning Algorithms", which is a happy thing to stumble upon. Edit: Just realised that I misread the parent comment and the link to the Info Theory book was intentional.
542458 5y ago
One thing that feels a bit strange to me is that he uses timelines of 1000 years when calculating nuclear reserves. I don’t believe we need a plan for the next 1000 years - think of what our understanding of power generation and transmission was a millennium ago. Assuming that we will still be using the same technologies in 1000 years seems a bit pessimistic to me.
- cbmuser 5y ago
  Physics won’t change in a thousand years and it’s very unlikely we’ll find anything more powerful and energy-dense beyond nuclear fission and fusion.
  - ben_w 5y ago
    On that timescale I expect us to engineer antimatter-based energy storage. Or do something literally incomprehensible — a thousand years ago we didn’t have the language to describe the language to describe relativity.
    - dredmorbius 5y ago
      Antimatter might conceivably be viable as a form of energy storage. But as with hydrogen or other synfuels, it would never be a primary energy source, and the losses in production of antimatter are likely to remain large. Ultimately, antimatter is a battery or fuel, not an energy source. And if it ever were a viable energy source ... well, we'd likely have bigger problems.
    - gnramires 5y ago
      It doesn't quite work like that. 1000 years ago Europeans (you may say) only traveled routinely within 1 continent. Today, they travel routinely to all 7 continents. You can't say in another 1000 years anyone will travel to 14 continents -- there's only so much Earth to discover :) We can know Earth in better detail, but it's inherently limited. In the same vein, there's no guarantee we will continue to discover revolutionary engineering strategies, and certainly no guarantee of discovering (or not discovering) new physics. In fact, physics has seen a slower pace of discoveries since mid-20th century. This kind of (not necessarily justifiable) optimism is in fact quite a risk when evaluating some technologies on sustainability.
samch93 5y ago
It‘s such a tragedy that he died so young. Prof Mackay was a role model who impacted our world in many positive ways (e.g. his work in information theory, Bayesian statistics, environmental science). I recommend his lecture on information theory which is available on youtube [1]. He also documented the progress of his cancer very detailed on his blog [2], which is a very interesting (and sad) read. [1] https://youtu.be/BCiZc0n6COY https://youtu.be/BCiZc0n6COY [2] http://itila.blogspot.com/?m=1 http://itila.blogspot.com/?m=1
mcot2 5y ago
It sounds like this should have a date attached to it as the numbers are quite outdated for todays world. This did have some good data for back when it was written of course. * An efficient EV will do less than 12kWh/100km these days. * Utility scale solar pv cost declines have been dramatic. It is now the cheapest form of new energy to deploy. * Developments in deep water off-shore wind have led to much larger turbines which are capturing more wind energy for longer periods of time. * Large scale batteries are now viable as a storage mechanism for renewables and are going to rapidly replace things like peaker plants. * Lots of new research is happening with Nuclear like thorium/molten-salt reactors which will still be important for baseload generation.
- credit_guy 5y ago
  > Utility scale solar PV [...] is now the cheapest form of new energy to deploy. I've been hearing this claim for a few years now, and I took it at face value, until a few days ago. I was having a discussion with a friend and told him that PV's share of electricity generation must by quite high, and then I checked the EIA website [1], and it turns out only 2.3% of the electricity comes from PV, while about 40% come from gas and 20% from coal. Something does not add up. If PV is so cheap, why don't we see more electricity being produced by PV? [1] https://www.eia.gov/tools/faqs/faq.php?id=427&t=3 https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
  - baybal2 5y ago
    > Something does not add up. If PV is so cheap, why don't we see more electricity being produced by PV? > Utility scale solar PV [...] is now the cheapest form of new energy to deploy For China... The West has very few semiconductor grade silicon smelters, and no industrial scale ones for PV ingots. I think all of PV cell makers in the West just dice Chinese boules
    - Robotbeat 5y ago
      Correct, EXCEPT for thin film cells by First Solar (who make the whole module). Although hopefully this is changing.
aborsy 5y ago
Before research into sustainable energy, David MacKay had rediscovered Low Density Parity Check (LDPC) codes in early 90s, perhaps the most common type of error correction codes used nowadays in commercial systems (alongside with Reed Solomon codes used for storage). He then worked on sustainable energy long before it became fashionable. His early death was a significant loss. He blogged cheerfully from hospital til few days before his death http://itila.blogspot.com/2016/04/perhaps-my-last-post-well-see.html?m=1 http://itila.blogspot.com/2016/04/perhaps-my-last-post-well-... Rest In Peace David MacKay.
barathr 5y ago
I highly recommend Prof. Tom Murphy's new book "Energy and Human Ambitions" (freely available as well) that is sort of a deeper dive into some of the questions that Mackay explored: https://escholarship.org/uc/item/9js5291m https://escholarship.org/uc/item/9js5291m
- spodek 5y ago
  I came here to write about Tom's book. I consider it Mackay's successor and called it The Science Book of the Decade in my review of it. He wrote it for non-science undergraduates. Here's the review: https://joshuaspodek.com/the-science-book-of-the-decade-energy-and-human-ambitions-on-a-finite-planet-by-tom-murphy https://joshuaspodek.com/the-science-book-of-the-decade-ener...
fghorow 5y ago
The original of this book is a wonderful resource. I am very happy to see a community bringing it up-to-date because MacKay had the foresight to license the work using CC.
ZeroGravitas 5y ago
I wonder if he'd be happy that his legacy seems to have just fueled fossil fuel funded conspiracies by adding some aura of credibility to their lies. I can't imagine he would.
olau 5y ago
There was indeed a lot of hot air in sustainability thoughts in 2008, and probably still is, but Mackay's treatment is sometimes bordering the absurd. For instance, the chapter on wind power starts by comparing a back of the envelope calculation on wind power with energy usage by a fossil car. While there are occasional good points, I would not recommend reading this book unless you actually know something about the things the book is discussing. It's simply too misleading in important places. In case anyone is wondering about this, there are real studies on the feasibility of 100% renewables by organizations that actually know this stuff and have done the modelling work.
- gnramires 5y ago
  Mackay's point is that you could get through the confusion relatively quickly, and showing in principle how to evaluate and fight the problem. I don't think it was meant as a final solution -- just to show that it was feasible, and approachable as a problem. Without getting into politics or ideology. I got a quite good intuitive sense of the scales involved, and at least for me Solar clearly reveals itself as an outstanding source of energy (at say 150W/m2).
- rufuspollock 5y ago
  Could you reference some of the "real studies" you mention - this would help update and amend MacKay's work.
pfdietz 5y ago
Didn't this book also assume substantial biomass energy grown in the UK? If I recall correctly, it was negative on solar due to land use, but that was mostly due to this biomass (which has extremely low energy capture efficiency, requiring a lot of land.)

168 points by rufuspollock 5y ago

Have a look at http://2050-calculator-tool.decc.gov.uk/ http://2050-calculator-tool.decc.gov.uk/ (I was David's Editor for "Sustainable Energy - without the hot air". There's been quite a bit of interest in updating the book, but there are obvious difficulties. If have suggestions, let me know. Niall Mansfield sewtha-2.0@uit.co.uk )

lucb1e 5y ago
I wonder if this is correct. Setting the nuclear slider to max single-handedly reduces emissions by 30%, decreases energy costs rather than increases, does not require land use change, improves air quality, and also reduces electricity demand by using the waste heat for district heating. Now add: (1.) electrification of freight transport, (2.) tackling the (relatively) quick wins in industry electrification, and (3.) carbon capture, and one gets to 75% emissions reduction with less than one percent of cost increase and zero behavioural changes (such as eating less meat or flying less often) are required. I can't find any other combination in this calculator that leaves nature so untouched, requires so little land use, requires no behaviour adjustment, or is so cheap while still reducing emissions meaningfully. (Well, geothermal is nearly as good but then its maximum potential is only a small percentage of energy demand and it's also a bit more expensive per Joule.) Probably the most unrealistic part is public support for the choice, but in a perfect world? Would it be this simple?!
- johnny53169 5y ago
  > (3.) carbon capture, and one gets to 75% emissions reduction with less than one percent of cost increase Carbon capture and less than one percent cost increase looks suspect to me
  - lucb1e 5y ago
    Agreed. I didn't use it at first because I thought it would be cheaper to just reduce emissions than undo emissions, at least up until this 80% goal that the site poses. Without any carbon capture, you're still at 61% emissions reduction and the cost actually decreases by 0.8% from today rather than increasing by 0.6%. If you get to 61% with the only change being "build nuclear and make use of it" (no lifestyle changes, no cost changes, no landuse changes), that would be amazing. Hence my main question is about the nuclear aspect. The argument against nuclear is usually that it's super scary and dangerous (easy enough to disprove that with numbers, so long as you're not talking to someone from germany) and the fallback argument is that it's so expensive now that PV+wind became so much cheaper. This calculator seems to show the opposite of that latter argument (when looking purely at price).
    - zbrozek 5y ago
      Surely there are studies of LCOE for both when trying to produce baseload capacity. Personally, I suspect nuclear construction costs are dominant, but that should also be addressible through improvements in technology and policy.
- m4rtink 5y ago
  Not a big surprise given the insanely high power density of nuclear reactors.
- addicted 5y ago
  This is strange considering nuclear continues to be the most expensive new form of fuel and has only been getting more expensive with every passing decade. There is new research in nuclear which if successful would bring costs down but it’s hard to see how maxing out on nuclear reduces average costs. Edit: I see now. The original data is at least over 5 years old, at which point it’s possible that wind/solar may still have been more expensive than nuclear. Editx2: The original book on which the original site is based was published in 2008/2009. It’s not clear how much of the data on this new site has been updated.
- sdenton4 5y ago
  See also, peak uranium : https://en.m.wikipedia.org/wiki/Peak_uranium https://en.m.wikipedia.org/wiki/Peak_uranium 2017 known supply is enough for 130 years at current usage (supplying about 10% of global energy). Each doubling of production halves the peak timeline. Basically no one expects discovery to outpace usage. So, at best, nuclear is a stop gap and part of a different long term solution. Which could be fine! But the extremely low LCOE and fast build time for modern renewables suggests that nuclear is simply losing the race for relevance.
  - korantu 5y ago
    Fuel is very small part in cost of nuclear generation; As fuel price start increasing, more sources become viable, including sea water. There is practically unlimited supply once it happens, and this is before accounting for reprocessing. (and reprocessing happens in France, for example)
    - sdenton4 5y ago
      Right, but the fuel cost goes up over time as extraction gets harder (eventually requiring entire new types of facilities, which themselves take a decade to build), even as wind and solar continue their exponentially decreasing LCOE cost curve. The exponentially decreasing cost curve is the part that I think people haven't actually internalized. The arguments on the pro-nuclear side are pretty much the same as they were ten years ago. (right down to 'we'll have thorium in ten years!') But things are very different now: It's like arguing for large scale investment in punch-card sorting machines circe 1960. Yes, the punch-card sorting machines can be used to manage all your bank data, but the digital processing are getting exponentially better with time and have been actually better for a couple years. But the proponents of punch card sorting machines haven't internalized the message yet.
      - cnlevy 5y ago
        > Right, but the fuel cost goes up over time as extraction gets harder Uranium demand is declining, there has been almost no Uranium prosection in the last decades; Therefore it's no wonder reserves are diminishing. If demand picks up, prospecting will renew, and a lot more uranium will be discovered. This is not accounting for thorium reserves, which have never been seriously prospected.
rufuspollock 5y ago
Thanks Niall - updating the book is exactly what we are hoping to do and still thinking the best form for that. Re that tool i've been in correspondence with one of the other creators re trying to understand the source code etc - see https://github.com/life-itself/climate/issues/2 https://github.com/life-itself/climate/issues/2
tito 5y ago
Rufus, terrific work here! Niall - great to see you here. My mind goes towards helping others with "powers of 10 math" about climate. SWITHA for me embodied this concept of "how to think about the climate" more than anything. That type of thinking is needed more now than ever. Even that line "2 billion years of energy reserves", so powerful.
deleted 5y ago
[deleted]

algo_trader 5y ago

Alas, this is probably pointless. Some technologies (PV, batteries, wind) have improved by an order of magnitude - and swamp out all other considerations. EDIT: to be clear, i loved the original book, and have re-read it several times over the years.

bjelkeman-again 5y ago
David MacKay’s work was for me very important. It showed how one should do a systems analysis for a country to understand how one can achieve the change required. I was astonished when I talked to several of the leading people responsible for energy policy in several political parties in my country, to find they really had no clue about what they where doing on a systems level. I think that updating this book is not pointless, but more importantly doing the same for more countries is really important.
- phreeza 5y ago
  It would be fantastic to turn the chapters into Templates where one has to plug in the relevant parameters for a country and see the calculations for that country.
  - algo_trader 5y ago
    And multiple PhD students have done so! For example, the Stanford/Jacobson study on powering the world with wind/solar/water. Some results were famously silly, such as filing Finland with solar panels, or adding the cost of nuclear war to nuclear reactors. Jacobson sued other academics then backed down. The point is, 5-10 years on, these models turned out to be over pessimistic! Australia doesn't need fancy modelling - simple roof top solar there is on target to meet full day time demand in 2-3 years. Conversely we still dont really know how to meet the last 5% of outlier energy demand scenarios.
    - selimthegrim 5y ago
      Has Jacobson stopped suing people though

lr1970 5y ago

Sir David Mackay [0] was a great mind who contributed major discoveries in Machine Learning, Information Theory, Coding Theory and Physics. His book "Information Theory, Inference, and Learning Algorithms" is a great resource for anyone learning ML and who wants to understand how ML, Information Theory and Statistics all fit together. The book is available for free download as a pdf [1] as well as for purchase. His untimely death from cancer in 2016 at the age of 48 is a big loss to Science. His book on Climate Change "Sustainable Energy without the Hot Air" (also available as pdf) [2] is a testament to breadth and versatility of his scientific interests. [0] https://en.wikipedia.org/wiki/David_J._C._MacKay https://en.wikipedia.org/wiki/David_J._C._MacKay [1] http://www.inference.org.uk/mackay/itila/book.html http://www.inference.org.uk/mackay/itila/book.html [2] http://www.withouthotair.com/ http://www.withouthotair.com/ EDIT: typos

femto 5y ago
Here's the download link for the Without Hot Air book: http://www.withouthotair.com/download.html http://www.withouthotair.com/download.html The parent's link was for his other book "Information Theory, Inference, and Learning Algorithms", which is a happy thing to stumble upon. Edit: Just realised that I misread the parent comment and the link to the Info Theory book was intentional.

542458 5y ago

One thing that feels a bit strange to me is that he uses timelines of 1000 years when calculating nuclear reserves. I don’t believe we need a plan for the next 1000 years - think of what our understanding of power generation and transmission was a millennium ago. Assuming that we will still be using the same technologies in 1000 years seems a bit pessimistic to me.

cbmuser 5y ago
Physics won’t change in a thousand years and it’s very unlikely we’ll find anything more powerful and energy-dense beyond nuclear fission and fusion.
- ben_w 5y ago
  On that timescale I expect us to engineer antimatter-based energy storage. Or do something literally incomprehensible — a thousand years ago we didn’t have the language to describe the language to describe relativity.
  - dredmorbius 5y ago
    Antimatter might conceivably be viable as a form of energy storage. But as with hydrogen or other synfuels, it would never be a primary energy source, and the losses in production of antimatter are likely to remain large. Ultimately, antimatter is a battery or fuel, not an energy source. And if it ever were a viable energy source ... well, we'd likely have bigger problems.
  - gnramires 5y ago
    It doesn't quite work like that. 1000 years ago Europeans (you may say) only traveled routinely within 1 continent. Today, they travel routinely to all 7 continents. You can't say in another 1000 years anyone will travel to 14 continents -- there's only so much Earth to discover :) We can know Earth in better detail, but it's inherently limited. In the same vein, there's no guarantee we will continue to discover revolutionary engineering strategies, and certainly no guarantee of discovering (or not discovering) new physics. In fact, physics has seen a slower pace of discoveries since mid-20th century. This kind of (not necessarily justifiable) optimism is in fact quite a risk when evaluating some technologies on sustainability.

samch93 5y ago

It‘s such a tragedy that he died so young. Prof Mackay was a role model who impacted our world in many positive ways (e.g. his work in information theory, Bayesian statistics, environmental science). I recommend his lecture on information theory which is available on youtube [1]. He also documented the progress of his cancer very detailed on his blog [2], which is a very interesting (and sad) read. [1] https://youtu.be/BCiZc0n6COY https://youtu.be/BCiZc0n6COY [2] http://itila.blogspot.com/?m=1 http://itila.blogspot.com/?m=1

mcot2 5y ago

It sounds like this should have a date attached to it as the numbers are quite outdated for todays world. This did have some good data for back when it was written of course. * An efficient EV will do less than 12kWh/100km these days. * Utility scale solar pv cost declines have been dramatic. It is now the cheapest form of new energy to deploy. * Developments in deep water off-shore wind have led to much larger turbines which are capturing more wind energy for longer periods of time. * Large scale batteries are now viable as a storage mechanism for renewables and are going to rapidly replace things like peaker plants. * Lots of new research is happening with Nuclear like thorium/molten-salt reactors which will still be important for baseload generation.

credit_guy 5y ago
> Utility scale solar PV [...] is now the cheapest form of new energy to deploy. I've been hearing this claim for a few years now, and I took it at face value, until a few days ago. I was having a discussion with a friend and told him that PV's share of electricity generation must by quite high, and then I checked the EIA website [1], and it turns out only 2.3% of the electricity comes from PV, while about 40% come from gas and 20% from coal. Something does not add up. If PV is so cheap, why don't we see more electricity being produced by PV? [1] https://www.eia.gov/tools/faqs/faq.php?id=427&t=3 https://www.eia.gov/tools/faqs/faq.php?id=427&t=3
- baybal2 5y ago
  > Something does not add up. If PV is so cheap, why don't we see more electricity being produced by PV? > Utility scale solar PV [...] is now the cheapest form of new energy to deploy For China... The West has very few semiconductor grade silicon smelters, and no industrial scale ones for PV ingots. I think all of PV cell makers in the West just dice Chinese boules
  - Robotbeat 5y ago
    Correct, EXCEPT for thin film cells by First Solar (who make the whole module). Although hopefully this is changing.

aborsy 5y ago

Before research into sustainable energy, David MacKay had rediscovered Low Density Parity Check (LDPC) codes in early 90s, perhaps the most common type of error correction codes used nowadays in commercial systems (alongside with Reed Solomon codes used for storage). He then worked on sustainable energy long before it became fashionable. His early death was a significant loss. He blogged cheerfully from hospital til few days before his death http://itila.blogspot.com/2016/04/perhaps-my-last-post-well-see.html?m=1 http://itila.blogspot.com/2016/04/perhaps-my-last-post-well-... Rest In Peace David MacKay.

barathr 5y ago

I highly recommend Prof. Tom Murphy's new book "Energy and Human Ambitions" (freely available as well) that is sort of a deeper dive into some of the questions that Mackay explored: https://escholarship.org/uc/item/9js5291m https://escholarship.org/uc/item/9js5291m

spodek 5y ago
I came here to write about Tom's book. I consider it Mackay's successor and called it The Science Book of the Decade in my review of it. He wrote it for non-science undergraduates. Here's the review: https://joshuaspodek.com/the-science-book-of-the-decade-energy-and-human-ambitions-on-a-finite-planet-by-tom-murphy https://joshuaspodek.com/the-science-book-of-the-decade-ener...

fghorow 5y ago

The original of this book is a wonderful resource. I am very happy to see a community bringing it up-to-date because MacKay had the foresight to license the work using CC.

ZeroGravitas 5y ago

I wonder if he'd be happy that his legacy seems to have just fueled fossil fuel funded conspiracies by adding some aura of credibility to their lies. I can't imagine he would.

olau 5y ago

There was indeed a lot of hot air in sustainability thoughts in 2008, and probably still is, but Mackay's treatment is sometimes bordering the absurd. For instance, the chapter on wind power starts by comparing a back of the envelope calculation on wind power with energy usage by a fossil car. While there are occasional good points, I would not recommend reading this book unless you actually know something about the things the book is discussing. It's simply too misleading in important places. In case anyone is wondering about this, there are real studies on the feasibility of 100% renewables by organizations that actually know this stuff and have done the modelling work.

gnramires 5y ago
Mackay's point is that you could get through the confusion relatively quickly, and showing in principle how to evaluate and fight the problem. I don't think it was meant as a final solution -- just to show that it was feasible, and approachable as a problem. Without getting into politics or ideology. I got a quite good intuitive sense of the scales involved, and at least for me Solar clearly reveals itself as an outstanding source of energy (at say 150W/m2).
rufuspollock 5y ago
Could you reference some of the "real studies" you mention - this would help update and amend MacKay's work.

pfdietz 5y ago

Didn't this book also assume substantial biomass energy grown in the UK? If I recall correctly, it was negative on solar due to land use, but that was mostly due to this biomass (which has extremely low energy capture efficiency, requiring a lot of land.)