Lowtech Graph lists low-tech options for every need of a home. Here you can compare them, find tutorials to build them, and link them together into a circular system. Why low-tech?
Natural light inside the house, as opposed to the sun's heat. Windows, roof lights, light tubes and light-coloured surfaces bring it in and spread it, so lamps stay off longer.
It arrives on the site on its own. Nothing in the catalogue makes it. In the builder you add it as “Daylight”.