Yesterday, I wrote an article about the energy we could get out of a fusion reactor in development. Today, it’s about the energy we could get from a fusion reactor already in service: the Sun.
Solar power lacks the flair of fusion, and I’m afraid the story of a plane that cruises at 43 mph probably won’t do much to help that along, but there’s a lot to the Solar Impulse that captures the imagination. There’s its magnificent wingspan, for instance:
That’s a 208 feet wingspan folks, dwarfing many airliners and bombers. The kicker is that the whole thing weighs in at a max takeoff weight of two tons – 4,400 pounds. It’s empty weight is about the same as your car’s. Think for a moment about the brilliant design and fine construction keeping the weight down must have required. There’s no two ways about it – just the size-to-weight issue makes this a marvel of engineering.
As long as it holds together, of course. And it did – it flew 19 hours from Madrid to Rabat, Morocco under the guidance of painfully-slow-flight expert Bertrand Piccard. It was a flight of 391 miles with an average speed of 31 mph. Okay, those are still not very glamorous numbers – I think the Hindenberg might have been faster – but it’s an example of the best in human endeavor – pushing our technology to its extreme not to kill each other, but to go places. If it’s slow, that’s fine, because that tells us where we are in solar power – not very far along. Whatever environmentalists might say, solar power is not ready for prime time. Eventually, though, projects like these will contribute to research so that solar power can gain the efficiency necessary to quell the skeptics and to be an actual alternative rather than complement to fossil fuel use.
The Solar Impulse HB-SIA, which completed the Spain-Morocco test, is going to get substantial upgrades to allow it to cruise at 39,000 ft (including cockpit pressurization, oxygen, and a 262 ft wingspan that will rival any aircraft except possibly the Spruce Goose) and to complete a transcontinental flight. Then, it’s only a matter of getting someone sane enough to pilot it on its very slow trip. For the round-the-world flight, they’re looking at a five leg trip with pilot changes, with each leg lasting three to four days.
Does this sound crazy? Well, I love people who attempt circumnavigations (well, except for Magellan), and this reminds me a lot of Burt Rutan‘s Voyager:
The Voyager was the first plane to circumnavigate the world nonstop without refueling. It took nine days to do it, and thankfully there were two pilots – Rutan’s brother Dick and Jeana Yeager – but they managed it. It’s still one of the most beautiful designs ever, and I continue to think of Burt Rutan as the last great aerodynamic innovator.
The Solar Impulse will never be quite as beautiful or remarkable as the Rutan Voyager, but the Voyager still burned fossil fuels so, it can at least be greener. And, if industry can get them some better batteries and panels, maybe they can eventually beat nine days. I’d call that a milestone: if a solar-powered aircraft could circumnavigate faster than the first fossil fueled aircraft to do it (without refueling, of course, but that’s obvious in the case of the solar-powerful aircraft anyway since it doesn’t carry its fuel), then solar power will have reached a turning point worthy of a boast. I look forward to that.