Albiasa Solar, a Spanish company, is planning a 200 MW concentrating solar plant in Arizona that will feature the capability of storing heat in molten salt, so it can continue to generate power throughout the night. The plant is expensive, with a cost estimated around $1 billion, but it will require no fuel and produce no waste. Hopefully, it will also provide experience that can be used to reduce the costs of such construction in the future.
All told, concentrating solar with energy storage is a very promising looking technology. It has many of the advantages of fossil fuel and nuclear plants, no fuel requirement, and good sustainability credentials. Plus, there is a lot of high quality solar land available in the southern US, as well as southern Europe, North Africa, and the Middle East.
Needless to say, this is a much more practical way to get 24-hour solar power than space-based systems would be.