Uncertainty about subsidies in Spain and – to a lesser degree – the United States has led to a flurry of activity to get installations finished before the expiration dates, but some analysts say a slight slowdown could be coming.

Like any business, the solar business hates uncertainty. And right now, there's plenty of it.

That's because government subsidies in Spain and the United States hang in limbo, leaving solar companies with a foggy picture of what 2009 will look like, according to a research note from Thomas Weisel Partners analyst Jeff Osborne this month.