“the researchers identified 500 watt-hours per kilogram as an important threshold for the energy density of a solar stratospheric aircraft’s battery. At that level, they argue, persistent flight becomes viable across many parts of the world where atmospheric conditions allow……By comparison, today’s commercial electric-vehicle batteries sit in the roughly 250 watt-hour per kilogram range, while experimental or specialty cells in the 400 watt-hour per kilogram range are already available. “We’re almost there,” Mascarenhas said. “Those cells are very expensive right now, but they’re getting cheaper very quickly.””
It’s a truism that war accelerates technology development, and we are certainly seeing it with the current Ukraine & Middle East wars. Now it seems another fundamental breakthrough is around the corner. The power of satellites has previously been restricted to a small club of those with the money and technology for space launch; soon it looks like that won’t be true.
Outside of warfare, could this tech be a telecommunications alternative for satellite constellations? They would be orders of magnitude cheaper and allow for huge amounts of redundancy. Also, they won’t leave you beholden to a Bond movie baddie on his private island HQ threatening to switch off your access.