According to solarbuzz.com the world solar pv market grew 62% in 2007 and reached a world record of 2,826 Megawatts of installed solar panels. As you can see Germany is leading the world when it comes to installed capacity of solar pv panels followed by Spain? Why is that Germany and Spain account for so much of the installed solar power capacity? It is because of their feed-in tariff system, an incentive that encourages people to make investments in solar panels because it makes financial sense for them to do so.
If you notice the incentives in the USA are not as great as the ones in Germany and Spain, therefore the installed capacity is a refelction of the incentives. In fact, Germany has HALF the amount of sun hours compared to the USA, therefore it’s easy to make the connection that solar pv does not thrive where the sun shines, but where the financial incentives are abundant.