Re:Fusion reactors: Not what they’re cracked up to be
by Robotbeat on Wednesday April 26, 2017 @02:22PM
(#14205585)
Even if you include TOTAL energy instead of electrical energy (in the US, electricity is responsible for 40% of energy use, so I'll use that as a guesstimate), and assume 100MW/km^2 instead of 150 (even though I already accounted for that in the cloudy winter day part), you're still producing about 3.7 times as much energy on that cloudy winter day than the total UK energy use. And that's before we use higher efficiency solar panels or deep sea hydrogen seasonal storage (the latter of which is one of the very few sensible seasonal energy storage methods).
It's an absurd claim to say it's impossible, and there's almost nothing more annoying than a source claiming to be "without the hot air" actually being full of plenty of hot air on absolutist claims like this. You don't correct BS by using equal and opposite BS.
(Most energy advocates I know do this... both renewable advocates and nuclear advocates, exchanging BS about the opposite technology. It's a clean energy circular firing squad, with the climate in the middle.)
Re:Fusion reactors: Not what they’re cracked up to be
by jcranmer on Wednesday April 26, 2017 @02:05PM
(#14205430)
Energy consumption here does not mean just current electricity usage. It also includes things like fueling cars and planes. Also, the 150MW/km² is apparently roughly the summer expected solar insolation; year-round average insolation comes out to ~100MW/km² per the book's numbers.
The total chart at the end came out to <https://www.withouthotair.com/c18/page_103.shtml>, with solar making up about 68 kWh/d per person.
That is false, though. Just a little math shows why.
The UK is 242,500 km². Nameplate solar capacity on that would be on the order of 150MW/km², so 36 Terawatts. UK average electrical consumption is 32 /Giga/watts. Assume solar produces 1/4 of that 36TW on average when it's sunny during equinox, so 9TW. Even on a pretty cloudy day on the winter solstace in London, you're still going to produce at least 1/10th to 1/20th of that much, so worst case of worst cases (cloudy day on solstice) you're looking at 450GW average if you cover the entire UK in solar panels. That's still over ten times the UK's average electrical consumption.
(I used UK instead of Great Britain, but that doesn't make much difference.)
I mean, the overall point that you wouldn't want to power the UK on solar alone is totally and completely valid (and I fully support the Hinkley Point C nuclear power plant, by the way), but the idea that it's literally not possible is BS.