"Sustainable Energy - Without the Hot Air" by David JC MacKay
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"Sustainable Energy - Without the Hot Air" by David JC MacKay
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Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#2I read this a couple months ago and loved it. It's a physicist looking at the hard numbers of energy consumption and (sustainable) production. It's the opposite of all the wishy-washy environmentalist hand waving that's out there.
Read this if you've ever wondered about how leaving the lights on compares to turning the heat down a degree compares to...
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#3I seriously like the numbers he's giving. He actually outright states what the theoretical max of certain technologies are, like if wind turbines covered the whole of the UK we would only extract 200kWh/d per person (which would involve the levelling of every city to blanket cover the country), and his estimate for the UK is 195kWh/d per person of usage.
Even his best-case production estimate (which would basically turn the UK into an importer of everything as 75% of our arable land would be producing biofuels) he states we would only likely get 180kWh/d/p and that's assuming the technologies don't conflict (like having 10sqM of PV and 10sqM of solar heaters on our roofs per person - so 80sqM of roof usage in a 4 person house - would be feasible, especially considering the amount of people in high rises). The actual estimates though, from the Institute of Electrical Engineers and a half-dozen others, puts the estimate at ~18kWh/d/p of renewable production, compared to our 180kWh/d/p of consumption. Big gap.
Basically our option if we want to cut carbon emissions as much as possible is to go nuclear. The US has a consumption of 270kWh/d/p and Canada has a consumption of 350kWh/d/p (due to heating use, in some places basically 8 months out of the year). Both the US and Canada are benefited by being the 3/4th largest country and the 2nd largest country, respectively, which might make us capable of going green without nuclear, especially Canada.
However the infrastructure costs, employment costs and everything else will be astronomical. Simply put the US cent/kWh cost for electricity generation speaks worlds, in the UK it costs roughly 4 cents/kWh for nuclear, 7 cents/kWh for onshore wind, and 11 cent/kWh for offshore wind. In Europe those costs can jump to 15-20 cents/kWh for onshore and offshore respectively while nuclear jumps only to 7 cents/kWh.
The usage of natural uranium in reactors and the reprocessing of fuel (MOX) can significantly cut down on costs, especially considering that ~$300,000 of palladium can be recovered from 1 ton of spent fuel during reprocessing. The MOX can then make a second cycle, bringing up the palladium content per kilo of fuel purchased. Palladium reprocessed from spent fuel is actually less radioactive than a granite counter top, and due to its emission type and half-life (6.5 million years) it eventually decays into silver.
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#4Thank god for physicists.
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#5Thank god for physicists.
To maintain balance we have politicians and bureaucrats.
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#6what a lot of you seem to miss is that we need to start cutting on wasted energy at the same time as we build more solar/wind/nuclear/tidal/etc.
it's not just about replacing hydrocarbons by equal amount of alternatives!
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#7I like how he dispenses with the fallacy of saving energy by unplugging DC adapters or TVs by focusing our attention on the high-energy cost activities (heating and transportation).
5 minute shower * (5 gal/min) * (440 BTU [to heat water 85 degrees]/gal ) = 11000 BTU or 3.223kWh or ~16 hours of 200-watt HDTV
1 gallon of gasoline = 115000 BTU or 33.7kWh or 10 5-minute hot showers
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#8What a clear way of explaining the problem. Very readable graphs too, I'm impressed!
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#9This is the book to read if you want to understand sustainable energy issues. The only part where it's weak is discussing the economics; I would have liked more material on the costs and how to make sure they're manageable.
And yes, it's refreshing to see a book on this subject written by someone who can do enough math not to fall for nonsense.
Re: "Sustainable Energy - Without the Hot Air" by David JC MacKay
#10I seriously like the numbers he's giving. He actually outright states what the theoretical max of certain technologies are, like if wind turbines covered the whole of the UK we would only extract 200kWh/d per person (which would involve the levelling of every city to blanket cover the country), and his estimate for the UK is 195kWh/d per person of usage. Even his best-case production estimate (which would basically t…
Perhaps "like" is too strong a word, but it's rather bracing to get an idea of how long high-energy civilization can last; barring some miracle like practical, cheap fusion power appearing in the next decade.
If I were to make a comparison to a work of fiction, it wouldn't be to Mad Max or The Day After Tomorrow; but to The Cold Equations, by Tom Godwin.