Solar dishes and sun cubes

Just looking around some old folders for info I dug up a few years ago on the subject of solar power.  The concept that caught my attention was of the solar dish engine.  This looks a lot like one of the uses for the hydrogen tank of the shuttle's external tank that I've written about. That idea for the external tank was to focus sunlight by using mirrors.  The focal point would be very hot and be useful for melting down metals.  However, if you would attach a stirling engine at that focal point, you could generate electricity instead.  That electricity could in turn be used for base operations on a space base, or be beamed down to the surface of the moon in order to provide power to a base there.

Here's another another concept called the Suncube.   This system looks modular, so perhaps it can be put together in a large system of these Suncubes to generate large amounts of power.  The Suncube uses a fresnel lens to concentrate the sun's rays onto the photoelectric cell.  This improves its output.  I saw of demonstration of this concept on a website before.  I don't have the link, though.  Anyway, the guy just put a fresnel lens over the photovoltaic cell, and the output increased dramatically.  Very convincing.