| The breakthrough cost is key. One of my recent thoughts is that it's not so much that renewables are expensive as that fossil fuels are insanely under-priced, though that gets into a pretty deep economic question of just what price and cost are supposed to be. For electrical generation, the problem with a fuel-based intermediary storage is that the net efficiency is quite low: 50% loss at fuel formation, at best 45% efficiency from thermal generation (Carnot's Law is a bitch). Fuel cell tech might offer an out, but the catalysts are rare and expensive (though if we can find an all-platinum asteroid out there, solar + synfuel + space-mined catalyst might offer advantages). Solar costs have fallen, but the efficiency is capped. Moreover, as panel costs fall they're dominated by less-fungible elements, mostly installation and maintenance. There's the 20-year life (multiple systemic decay pathways) which means you need to replace 5% of your total stock every year. I'm not arguing against solar, but rather, against an abudant-energy future. Even with energy issues addressed, many other factors, including literally dirt (well, topsoil), challenge humans. Leibig's Law of the Minimum is another bitch. |