Bill Gates says there will be a "clean energy breakthrough" that will solve the global heating problem.

Mr Bill's faith in future technology is touching, but it's lunacy. Such a breakthrough may or may not happen. Our plans for avoiding global heating disaster must not depend on it.

Fortunately, we can avoid disaster even without any breakthrough — if we have the political will to make a forced march to sustainable energy. If, that is, we do not justify laziness by assuming that a "breakthrough" will make it easy.