[jjk166]

The main impediment to roof-top solar is actually the roof tops themselves. Most were not constructed with the weight of solar panels in mind, nor are all roofs built to a common standard. Thus every roof needs an expensive inspection to see if it can have solar panels mounted as-is, and if not you also need an expensive custom plan to reinforce the roof.

Also the grid is really not designed for large amounts of decentralized power generation. While modifying the grid is probably easier than replacing roofs en masse, it's still expensive. Dedicated solar plants can take advantage of economies of scale.

[Glavnokoman]

You are right. But isn't it sad and wrong that destroying wilderness is less expensive than fixing the roof?