I would have preferred to respond in public earlier, but was muted at the time. Thank you for including me in this conversation. You take issue with my tone, and with MacKay's. I take issue with using the words "very little land" and "tiny" to describe the space requirements of solar. But physics, not sentiments, will decide whether solar is viable. So I enthusiastically support running the numbers. MacKay gives a peak solar energy of 1000 W per square meter, over 90 W per square foot. So we can hope that the 7 watts of today's panels will continue improving. Seven watts per square foot gives 195 MW per square mile. So 2.9 terawatts / 195 megawatts per square mile = 14,871 square miles. How big is that? It depends on what you compare it to. I find it disingenuous to compare it to the continental United States. A test range is also simply a shape drawn on a map. A solar installation would be an engineering megaproject; we should compare it to other engineering megaprojects. Small towns are mere dots on the Nevada map, the Hoover Dam is invisible. The floor space of the Pentagon is a fraction of a square mile. Fresh Kills landfill is four square miles. No one thinks Elon Musk actually wants to build a solar facility the size of New Jersey in the desert. But he is definitely advocating when he characterizes solar as realistic for more than a small portion of our energy needs. If he wants to spend his own money on energy innovation, I salute him, but he is clearly willing to spend other people's money.
I'm starting to remember why. Here's crescent dunes. It's 1700 acres of mirrors, 2.6 square miles, in the middle of thousands of square miles of nothing. It's good for 500 GWh and cost about a billion dollars. 500GWh is a long road from 25,000 TWh. We'd need 50,000 of them to meet our yearly power requirements. That's a 50 trillion dollar investment. Nobody thinks we're going to do that. Nobody thinks we're going to build a photovoltaic array a hundred miles on a side, either. Not you, not me, not Bob Mackay. Not anyone who has ever so much as paid $12 for a Radio Shack solar panel capable of generating half a watt. Those of us who have worked on solar-electric hybrids have a pretty firm grasp on the disappointments of solar. But 25 thousand TERAWATTS is a staggering number. It's Doc Brown's "Two point twenty one jigawatts!" with four more zeroes. It's the kind of math that makes you lose hope. Hundred miles on a side? You can wrap your head around that. You'll never build it - it's 3,000 times the size of that very-impressive heliostat out in the middle of the Nevada desert. But fuckin' A, we can build a few. And at the cost of the Iraq War, we could have built 1700 of them for a power generation of 850TWh. STILL a long goddamn way from 25 thousand terawatts but you know what? It's a percentage. It's a start. And it's in human numbers, broken down to size that people who haven't read Bob Mackay can understand. And that's my beef - I threw out a flippant comment to make a point that renewable energy is within the realm of contemplation. You're going to the mattresses to argue that people aren't allowed to be flippant because you read a book. "How big is that?" About as big as I said. Is it "simply a shape drawn on a map?" Fuck yes. Because without drawing a shape on a map it's all a bunch of fuzzy numbers. How fuzzy? Well, according to MIT there is more surface area of the United States covered by parking spaces than there is covered by Puerto Rico - 3500 square miles in fact. Fuck Nevada - let's put a panel on top of every garage and cut our energy needs in half. And now we're back to your buddy Elon and realistic goals and nobody even had to call anybody else an asshole.I would have preferred to respond in public earlier, but was muted at the time.
We agree on this. And I think we agree that drawing a square on a map can help people wrap their heads around what that number represents. When I draw the square, I say "Golly! I have to zoom in three clicks before I can see the speck that is the Hoover Dam. Maybe solar is not yet ready for prime time, even if we could overcome the storage and transmission challenges." When Elon Musk draws the square, he says "actually very little land is needed to get rid of all fossil fuel electricity generation in the United States" and his map has the title "Surface area of solar panels required to power entire U.S." He would make a Dyson sphere look small by drawing it next to the Milky Way. Elon Musk is a visionary, a dreamer, and a savvy marketer. Attracting investment is his game, and he does it well. If his reality distortion field gets private investors to sign up, and the result is cool luxury cars and awesome rockets and better solar power, I am all for it. When he dips into the same public funds that brought us Solyndra and Fisker, I have reservations. I want to see reality as it is. The numbers show that, for now, the words "solar" and "power entire U.S." should not appear in the same sentence. There is a niche for solar. Pilot projects are useful. More research and development is warranted. I didn't interpret your flippant comment as a serious policy proposal. But the "tiny" typo gives the reader the wrong idea, I think. b_b appears to have anticipated that readers would conclude that "it's such a small area." Renewable energy takes a staggeringly large amount of area. 100% solar would require about as much as there is paved road in the lower 48. Hmm. If "more worthwhile than war" is the standard, then sure, we should build giant pyramids covered in solar panels. If "making responsible use of resources" is the standard, then I don't see solar contributing more than 1% of consumption anytime soon.25 thousand TERAWATTS is a staggering number.