Top all-time · #255
David MacKay
Personal blog · withouthotair.comscienceeconomics
David MacKay's personal blog at withouthotair.com covers science and economics. Since 2008, 185 different Hacker News readers have linked it 324 times, most often “ David MacKay: Sustainable Energy - without the hot air”. No feed was found, so read it on the site itself.
Sometimes recommended · 13 of 40 sampled comments recommend it?
Why HN links it
HN readers link David MacKay's free book Sustainable Energy Without the Hot Air for its back-of-the-envelope energy and climate calculations on renewables, nuclear and transport.
- Recommended for · 13 comments
- Called the book excellent and very readable; praised for its clear energy math and for being free online.
Summarised by Claude from a sample of 40 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
Most-linked posts?
- David MacKay: Sustainable Energy - without the hot air55 people · 66 mentions · first linked 2008-06-20
- Sustainable energy without the hot air (2008)38 people · 43 mentions · first linked 2016-06-17
- "Sustainable Energy - Without the Hot Air" by David JC MacKay7 people · 7 mentions · first linked 2009-06-23
- Sustainable Energy Book7 people · 7 mentions · first linked 2020-01-11
- /c19/page_114.shtml6 people · 6 mentions · first linked 2018-11-06
- /c18/page_103.shtml5 people · 5 mentions · first linked 2014-01-31
- Cambridge physics prof analyzes sustainable energy debate5 people · 5 mentions · first linked 2009-04-09
- /4 people · 5 mentions · first linked 2009-02-10
- Sustainable Energy – without the hot air4 people · 5 mentions · first linked 2012-12-01
- /c24/page_168.shtml3 people · 6 mentions · first linked 2013-08-22
What Hacker News says?
> how do we provide energy ...? Renewables might work - if people stopped having kids for a while It seems like you haven't done the math. I have. You're ridiculously wrong. US marketed energy consumption per capita is 9.5 kW (see https://en.wikipedia.org/wiki/List_of_countries_by_energy_co... ). That's 9.5 square meters of sunlight. If we pessimistically assume that we can only site solar panels on land (29% of Ear…
Comment linking /c24/page_172.shtml
on “How Technology Hijacks People’s Minds”Submitted Sustainable energy without the hot air (2008) as a story · 151 points
HN discussionWhat I would call "quantitative environmental consciousness" - things like estimating energy consumption and carbon footprints. Topics like energy policy and CO2 emissions will become increasingly critical in our lives, and yet you don't find many people reasoning about them in a lucid and informed way. A great place to start is the SEWTHA book by MacKay: https://www.withouthotair.com/
Comment linking /
on “Ask HN: What Skills to Acquire in 2020?”Submitted "Sustainable Energy - Without the Hot Air" by David JC MacKay as a story · 71 points
HN discussionThe book used a very pessimistic 10% efficiency for panels installed in large scale solar farms: https://www.withouthotair.com/c6/page_41.shtml If a breakthrough of solar technology occurs and the cost of photovoltaics came down enough that we could deploy panels all over the countryside, what is the maximum conceivable production? Well, if we covered 5% of the UK with 10%-efficient panels, we’d have 10% × 100 W/m2…
Comment linking /c6/page_41.shtml
on “We're going to need a lot of solar panels”Submitted Cambridge physics prof analyzes sustainable energy debate as a story · 17 points
HN discussionThe amount of solar panes we need was first impressed upon my by David Mackay's "Without Hot Air"[1]. I personally think solar is a useful tool for certain applications, but powering all of humanity with it feels like a step backwards paradigmatically. Really roughly speak we can think of solar as a step forward in human compatible photosynthesis. Humanity went to another tier of energy when we started to harness fi…
Comment linking /c6/page_38.shtml
on “We're going to need a lot of solar panels”Submitted David MacKay: Sustainable Energy - without the hot air as a story · 6 points
HN discussionIf you only read one book on the subject, read Dr David MacKay's Sustainable Energy Without The Hot Air . It clearly explains how we use energy, how we produce it and how we can sustainably match supply and demand. It gave me an intuitive understanding of energy, using quick order-of-magnitude calculations to figure out the really important issues. It's written from a British perspective, but the principles are univ…
Comment linking /
on “Mumbai bans plastic bags, bottles, and single-use plastic containers”Submitted Sustainable Energy – Without the Hot Air as a story · 3 points
HN discussionI don't think this is a reflection on the amount of usable sunlight on that hits the surface of the earth. It sounds more like a vague, general statement and isn't backed by calculations in the article. The late Professor McKay (whose book on information theory and ML is neat by the way) published a great book full of climate back of the envelope calculations, Whithout the Hot Air , which is available online[1]. He…
Comment linking /c18/page_103.shtml
on “Donald Trump’s Contract with the American Voter [pdf]”Submitted In depth comparison of different energy sources as a story · 3 points
HN discussionAir travel is bad for the environment, but only because the distances are long compared to driving. The fact that planes take lots of energy to propel through the air is defrayed by the fact that you can pack a lot of people on a plane - both typically consume on the order of .5 kWh of energy per kilometer of travel. Rail and buses are, of course, an order of magnitude lower.[1] You can talk about all the other ener…
Comment linking /c20/page_121.shtml
on “Defeated”Submitted Sustainable Energy – without the hot air as a story · 3 points
HN discussionAdjusted for your own seat, assuming a full plane. You can read about the calculation in the linked book. http://www.withouthotair.com/c5/page_35.shtml
Comment linking /c5/page_35.shtml
on “Tesla buys $1.5B in Bitcoin, may accept it as payment in the future”Submitted Sustainable Energy Book as a story · 2 points
HN discussionOur biggest environmental footprints as individuals are heating and cooling. Having an electric car is nothing compared to it. Take one intercontinental flight and again, having a fossil fuel car for a year does not exceed the emissions of that flight. http://www.withouthotair.com/ Legitimizing Bitcoin has nothing to do with the environment in the large scale of things. It's like saying that you need to optimize fas…
Comment linking /
on “Tesla buys $1.5B in Bitcoin, may accept it as payment in the future”Submitted Sustainable Energy – Without the Hot Air as a story · 2 points
HN discussionIt's always about cost, if it wasn't about cost we could just build so much PV/Wind + Power to Gas/Liquid Facilities as we need and be done with it. And building new nuclear is way more expensive than projected in your link , (No blame to the authors, 10 years ago they couldn't know that those numbers are not realistic) while Wind/PV are still becoming cheaper every year) they assume ~1,3 Billion per 1 GW nuclear ca…
Comment linking /c28/page_216.shtml
on “Nuclear power is the fastest way to slash greenhouse gas emissions, decarbonize”Submitted Sustainable energy without the hot air (2015) as a story · 2 points
HN discussionhttp://withouthotair.com/ "A vital tool agains global warming" means that it's our only possibility. It's not about cost, it's about what is physically possible.
Comment linking /
on “Nuclear power is the fastest way to slash greenhouse gas emissions, decarbonize”Submitted Sustainable Energy Book as a story · 2 points
HN discussionIf you are interested in some numbers about the subject, there is very good resource for the case of British isles. The situation is of course different for USA the people per area is different. But you anyhow can get a grasp why renewables are problematic. http://withouthotair.com/
Comment linking /
on “Nuclear power is the fastest way to slash greenhouse gas emissions, decarbonize”Submitted Ch 29 Page 229: Sustainable Energy – without the hot air as a story · 2 points
HN discussionWell, according to "Sustainable Energy Without the Hot Air" >Japanese researchers have found a technique for extracting uranium from seawater at a cost of $100–300 per kilogram of uranium, in comparison with a current cost of about $20/kg for uranium from ore. Because uranium contains so much more energy per ton than traditional fuels, this 5-fold or 15-fold increase in the cost of uranium would have little effect o…
Comment linking /c24/page_174.shtml
on “Small nuclear reactors: tiny NuScale reactor gets safety approval”Submitted Numbers on Sustainable Energy as a story · 2 points
HN discussion>planes use most of their energy to not crash into the ground Surprisingly, not by much! To the first approximation an optimized plane will use 50% of its power during cruise generating lift ("not crashing into the ground"), and 50% of its power overcoming drag.[1] The tie is broken because planes expend extra more energy climbing than they save descending, and that's also part of "not crashing into the ground." :)…
Comment linking /cC/page_272.shtml
on “Silent and Simple Ion Engine Powers a Plane with No Moving Parts”Submitted Sustainable Energy – without the hot air as a story · 1 points
HN discussionDavid MacKay disagrees; the book estimates[0] that we could double our uranium use and keep it up for 1000 years, and that's without touching the sea water deposits (~200x more than on land), and without using more efficient reactors, both of which together enabling scaling up nuclear by 2 orders of magnitude without running out of fuel this milennium. The article from phys.org you quote doesn't show its math much;…
Comment linking /c24/page_162.shtml
on “Remembering Roger Boisjoly: He Tried to Stop Shuttle Challenger Launch”Submitted Sustainable Energy Without the Hot Air as a story · 1 points
HN discussion
