they're also more efficient than drywall, but I'm not going to clad my bedroom in them, because it would be a waste of money. Because the economics matter, we

they're also more efficient than drywall, but I'm not going to clad my bedroom in them, because it would be a waste of money. Because the economics matter, we have to understand if it's a better value versus asphalt + solar, or asphalt + ground fixtures, or asphalt + a solar farm.