I just received a pamphlet with my last electric bill from Potomac Edison in Maryland that broke down where the electricity they provide comes from. I don't have it in front of me, but I recall the percentage of solar power stated as 0.02%, vs. numbers in the 30-40% range or so for nuclear, oil and coal.
Even with the rapid adoption of solar panels on roofs of residences and businesses, I find it hard to believe it will really break their business model any time soon?
For example, one of the largest solar installations I know of in the area is at American Public University in West Virginia. They have a several hundred kilowatt installation (I think someone said around 430 Kwatt but don't quote me on that), but they also have at least a dozen office buildings to power -- so all of that STILL produces well under half of their power needs.
I'm trying to get solar panels installed on my house right now, and even the most optimistic engineering model their computer software could come up with for my property wouldn't generate over 67% or so of my average power needs. The problem is, you're limited by how much roof space you have that faces the right direction -- and the more efficient panels cost a big premium price too. (If you do those no money down or low money down solar loan/lease arrangements, they often only agree to supply the cheaper Asian-made panels that don't have the especially high outputs. In my case, we were looking at no more than about 40% to 42% of my needs supplied with those panels.)
If the power companies would invest in the long-term, instead of trying to fight all changes with legislation -- they could use all of this to great advantage. It looks to me like your typical solar user is still going to need to be supplied 30-50% of their power from the power company. (Battery storage tech. is still just not really cost effective on a large scale, so solar panels mean you're not able to use your own electricity after dark or during storms where skies are dark.) So they need to simply scale back how much they spend on things like coal, oil and natural gas for generating power as more solar panels come online. Share around the power they generate during the day, and use the traditional power plants after dark. They're going to be able to collect fees for the power distribution, regardless.