How much was the price of solar panels 5 years ago compared to now?
For just 5 years ago, certainly not! Perhaps you are thinking of 50 years ago, the kind that was put on the early communication satellites? 5 years ago, there was a glut of polysilicon, so modules were actually a little cheaper than today. Solar cell makers were basically using the scraps thrown away by chipmakers. But today, more silicon goes into making solar cells than computer chips, so that bonanza is gone. We will see prices going lower this year, possibly 20% from last year, because of improvements in technology, but also an increase in polysilicon supply, and a slowdown in demand due to worldwide recession. Later this year is a good time to buy panels, if you have the cash. The industry site below tracks module prices. They used to have more data, but I guess the old data rolls off the screen with time. If you want to see the details, they'll charge you for the report.
I okorder.com to register for free and lock in long term costs. The increasing demand and competition is helping reduce costs.