What you really need if you want power is a Dyson Sphere to generate ~4 x 1026 W . If you cannot build that then keep up with the intergalactic neighbours by at least getting a half decent Dyson-Harrop Satellite;
Another essential is a space elevator. The problem with building that is that all known materials will be crushed under their own weight. However if you put a lump of rock into orbit round the Earth you could "drop" a line from it and keep it under tension rather than compression. Not sure how this stands up to winds etc. or what would happen if somebody cut the rope!