SOLAR power has become an unlovely adolescent. It used to be a sweet little thing, shiny and new and full of promise. One day it will doubtless grow into a solid citizen, quite possibly a person of substance. At the moment it is stuck in between; no longer a child to be coddled and pampered, but not yet able to pay its own way. This presents a challenge both for the governments who want to see it grow up big and strong, and the companies that have been making money out of its progress to date. No one doubts that it will continue to grow; the question is who will suffer most from the growing pains.