Ever walked into a room with the sun shining through a big glass window? If the glass was not treated or the shades were not drawn, you have a hot spot, or high heat area, usually uncomfortable. Imagine this on the scale of a skyscraper. Solar shading in the form of mechanical shades transforms the heat gain into usable power. More comfort and less waste is a reasonable solution.
Solar shading could be a solution for global warming, but global warming is being called into question, so such a solution might not even be needed. But from a technical standpoint, it seems to be a viable solution, and it could even be a source renewable energy. But then again, I think the free market would have to be utilized to develop and implement better methods to get into space.