That's a brilliant idea. The only problem is, we don't have the technology.
Sure we can make something as bright or even brighter than the sun in term of brightness per unit area. However, even if we cover our whole planet with this light, it has to be 10 thousands brighter than the sun to get the same output as the sun since the sun is 10 thousands bigger in area. And then TNOs receive double brightness. I don't think it really helps. And the for all the energy of humankind has collected the entire human history, cannot light it up for a second. At the current rate of our entire population increasing energy consumption, sustaining it running is not achievable for thousands of years, even if we put all our energy harvested to it.
I am sure we have better ways to do it as well as better use of the energy now or later.