How in the world would “expectations of future regulation” bring down the price? If anything it would raise prices since people will have fewer choices.
The expectation was that government was going to ‘regulate’ their market competition, giving them an additional advantage, and raising their competitors’ prices.
Regulation would not bring down the price of solar or wind but would raise the cost of fossil fuel competitors; e.g., the EPA's rules for clean coal that, in effect, prohibit the construction of any new plants.
Meaning, if Obama has his way, our costs for energy will "necessarily skyrocket," as he stated during 2007. But skyrocketed electricity costs kind of make even solar and wind competitive.