There's nothing wrong with going the solar route, infact if you access to solar or hyder power should be a key criteria in selecting a location to setup a farm.
It is however not very wise to spend money setting up a solar farm for the express purpose of mining, simply because you could be spending that money on expanding hash instead.
Sure the running costs will be lower with solar, and unlike what people seem to be speculating, it should pay for itself in 5 years, but you are adding one more variable to a delicate mix.
I like these conversations regarding solar power to get everyone's thoughts, positive or negative as it has helped me in the direction I want to go.
Most of us do not have access to cheap power and the price for grid power will only go up in the future.
So for myself, I will be investing in more solar, for the small miner I believe it is the only way to mine in the future unless you are lucky and already have access to this cheap power.
I am developing two different automated systems that substantially cut the costs associated with solar.
This is a long game for me, I will invest in the power infrastructure first.