Top all-time · #3916
Chris Goodall
Personal blog · carboncommentary.com/blogeconomicsscience
Chris Goodall writes Carbon Commentary, a personal blog at carboncommentary.com about economics and science. Since 2016, 20 different Hacker News readers have linked it 27 times, most often “Keeping David MacKay's 'Sustainable Energy – without the hot air' up-to-date”. It is still writing: the last post was on 2026-10-27, and you can follow it by feed.
Too few sampled comments (20) to say how often HN recommends it.?
Why HN links it
HN readers link Chris Goodall's posts as sources on hydrogen, nuclear, carbon capture and transport emissions, and as updates to David MacKay's 2008 energy book, which commenters say has become outdated.
Summarised by Claude from a sample of 20 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
A critical appraisal of issues in the move to a low-carbon economy. Chris Goodall is the author of "Sustainability: All That Matters" and "Ten Technologies to Save the Planet".
Most-linked posts?
- Keeping David MacKay's 'Sustainable Energy – without the hot air' up-to-date7 people · 9 mentions · first linked 2017-03-31
- /blog/2017/7/5/hydrogen-made-by-the-electrolysis-of-water-is-now-cost-competitive-and-gives-us-another-building-block-for-the-low-carbon-economy2 people · 2 mentions · first linked 2021-08-15
What Hacker News says?
This book is from 2008, and, while reportedly very good for its time, now out of date. https://www.carboncommentary.com/blog/2017/3/30/l6qcqgoedse1... In particular, nobody back then anticipated how quickly solar PV prices would drop. https://rameznaam.com/2020/05/14/solars-future-is-insanely-c...
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “Sweden’s incoming cabinet says new nuclear reactors will be built”Submitted Keeping David MacKay's 'Sustainable Energy – without the hot air' up-to-date as a story · 106 points
HN discussionThat book was a helpful contribution to the debate when it was published in 2008, but by 2017 people were already pointing out[0] its obsolete assumptions about renewables, and there is now an open source collaborative effort to produce a more accurate and up-to-date version.[1] I don't want to speak ill of the late great David MacKay, but it does seem that reality has exposed his pro-nuclear bias, which was already…
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “Germany to Rethink Nuclear Shutdown as Energy Crisis Deepens”Submitted Renewable energy unambiguously reduces UK wholesale power prices as a story · 5 points
HN discussionNote that while it is an excellent book, some of its contents are outdated now as it was published in 2009. In particular: solar, wind and battery technology have improved much faster than predicted. This blog post discusses some possible updates that could be made to the book: https://www.carboncommentary.com/blog/2017/3/30/l6qcqgoedse1...
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “Scotland to use 100% renewables on time to host 2020 climate summit”Submitted UK electric car sales started growing by 7% a month in 2019 as a story · 4 points
HN discussion> with bike/bus/walking space is an incredibly high impact carbon reduction strategy. It is not. On a CO2 per mile bases cars emit less than non-vegan humans, because it takes a lot of energy to grow food. If you put 2 people in the car it's not even close. https://www.carboncommentary.com/blog/2014/07/22/walking-can... http://web.mit.edu/2.813/www/readings/DrivingVsWalking.pdf > but after it takes place everyone ag…
Comment linking /blog/2014/07/22/walking-can-be-more-carbon-intensive-than-driving
on “Paris to ‘get rid of 70k parking spaces’”Submitted 'Renewables plus hydrogen' – almost all that we need as a story · 2 points
HN discussionA summary of the virtuous cycle created by cheap renewables and hydrogen electrolyzation: https://www.carboncommentary.com/blog/2020/6/17/renewables-p... Lots of comments on this thread that reveal folks are up to date with the state of hydrogen infrastructure c. 2017. It's changing really fast as billions of dollars are poured into R&D and pilot projects. For example, storage and transport: https://uk.reuters.com/a…
Comment linking /blog/2020/6/17/renewables-plus-hydrogen-almost-all-that-we-need
on “After many false starts, hydrogen power might now bear fruit”Submitted Lessons from the collapse of GE as a story · 2 points
HN discussionI read this analysis of the SMR farm announcement in Canada a few months ago and I found it quite insightful: https://www.carboncommentary.com/blog/2025/5/11/the-first-te...
Comment linking /blog/2025/5/11/the-first-test-for-new-small-modular-reactors-smr
on “Microsoft doubles down on small modular reactors and fusion energy”Submitted How much space will a 100% renewables UK require? as a story · 1 points
HN discussionI also recommend this book heartily - it's amazing. There have been mutterings about crowdsourcing an update, and I think I saw a github repo once but I can no longer find it. Here's an example: https://www.carboncommentary.com/blog/2017/3/30/l6qcqgoedse1...
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “Scientists say we’re on the cusp of a carbon dioxide–recycling revolution”Submitted The Time Needed for Energy Transitions as a story · 1 points
HN discussionI posted this about David MacKay's book "Sustainable Energy - without the hot air", which advocates nuclear energy, to a discussion about solar panels, and llukas pointed out that solar power development has exceeded MacKay's expectations, and linked to a page with updates, and dane-pgp also posted some interesting criticisms and links. If Solar Panels Are So Clean, Why Do They Produce So Much Toxic Waste? (forbes.c…
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “Nuclear power is the only green solution (2004)”What that article doesn't address is the concurrent shift to electrify domestic heating. A worked analysis of the impacts can be found here: https://www.carboncommentary.com/blog/2022/2/11/how-much-ele...
Comment linking /blog/2022/2/11/how-much-electricity-will-the-uk-need-as-it-switches-to-electric-heating-and-cars
on “Porsche's idea for a six-stroke internal combustion engine”Very good book but tech went lot further than David expected in many places (ie. solar power efficiency vs price). This page tried to keep it updated: https://www.carboncommentary.com/blog/2017/3/30/l6qcqgoedse1...
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “If Solar Panels Are So Clean, Why Do They Produce So Much Toxic Waste?”https://www.carboncommentary.com/blog/2021/7/30/the-struggle... Carbon sequestration is probably going to be important, but if it in any way enables more fossil fuels to be burnt, then it's probably a net negative. We need it to take stuff back out of the atmosphere, not extract and then store yet more fossil Carbon.
Comment linking /blog/2021/7/30/the-struggles-to-make-ccs-work
on “Gen Z members flock to climate careers”Covestro, a German company, already has a signed contract and made advance payments to receive the equivalent of up to 100,000 tonnes of green hydrogen (GH2) per year commencing 2025. A kilogramme of hydrogen - the unit most often used – has an energy value of about 33.3 kWh.[1] So a tonne of hydrogen delivers about 33 MWh and a million tonnes about 33 terawatt hours (TWh). To provide a sense of scale, the UK uses a…
Comment linking /blog/2021/6/11/some-rules-of-thumb-of-the-hydrogen-economy
on “Using copper to convert CO₂ to methane”That's between 1.5 and 2 million tonnes of hydrogen .. in a world that currently produces about 74 million tonnes of hydrogen annually already. There are multiple sources for those interested, https://www.carboncommentary.com/blog/2021/6/11/some-rules-o... is a brief dot point page, the Hydrogen UK and European Hydrogen Backbone reports are longer more detailed technical report papers.
Comment linking /blog/2021/6/11/some-rules-of-thumb-of-the-hydrogen-economy
on “Germany solar power output jumps to record highs”"The struggles to make CCS (Carbon Capture and Storage) work" https://www.carboncommentary.com/blog/2021/7/30/the-struggle...
Comment linking /blog/2021/7/30/the-struggles-to-make-ccs-work
on “How green is blue hydrogen?”State of the art is about 93% efficiency for electrolysis of water "in the lab". It was about 80% efficient at industrial scale back in 2017 (see https://www.carboncommentary.com/blog/2017/7/5/hydrogen-made... ), so we can expect that to be a few percentage points higher today. Apart from the aforementioned hydrogen agreement with Canada, construction is underway for a wind-powered multi-GW electrolyzer plant in the…
Comment linking /blog/2017/7/5/hydrogen-made-by-the-electrolysis-of-water-is-now-cost-competitive-and-gives-us-another-building-block-for-the-low-carbon-economy
on “The world’s first hydrogen trains started passenger service in Germany”That reference is pretty out of date now. Some people have considered updating it with more recent figures: https://www.carboncommentary.com/blog/2017/3/30/l6qcqgoedse1...
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “Driving a "Green car" vs cycling”Efficiency of a production electrolysis plant today is about 80%, which really doesn't seem that bad. https://www.carboncommentary.com/blog/2017/7/5/hydrogen-made...
Comment linking /blog/2017/7/5/hydrogen-made-by-the-electrolysis-of-water-is-now-cost-competitive-and-gives-us-another-building-block-for-the-low-carbon-economy
on “Plasma Kinetics May Revolutionize Hydrogen Storage for EVs”https://www.carboncommentary.com/blog/2017/3/30/l6qcqgoedse1...
Comment linking /blog/2017/3/30/l6qcqgoedse1wmjjz87t09usoq6jva
on “Ask HN: Book recommendations for renewable energy and climate change?”" We can expect 48% of the energy from renewable electricity to be lost in conversion to liquid fuels, using the average value for drop-in diesel technologies from our previous economic modeling work. To compound the problem, according to various studies 70% of the energy in those fuels will be lost when they are combusted in internal combustion engines, for a total efficiency of 16% for the e-fuels pathway. Therefo…
Comment linking /blog/2021/11/18/how-much-will-electrofuels-cost
on “First planned small nuclear reactor plant in the US has been canceled”From the atmosphere, sure. But, if they can succeed in building a viable conversion system, then hot exhaust from factories or other sources can be used instead of air. It could be a closed source system too, for example, in industrial applications that need a lot of heat. An almost closed cycle system may be viable. I have no information about the speed of the reaction, but I guess systems can be scaled. Also, a go…
Comment linking /blog/2017/7/24/exytron-the-worlds-first-power-to-gas-system-with-integrated-co2-collection-and-reuse
on “Fuel from the sky: Cheap hydrocarbons from CO2 direct air capture and sunlight”
