how to re-direct sunlight

Google solar tube.

It's basically a tube, sometimes with a mirror on the top that tracks the sun, that goes down to where you want light.

The problem is that you really need the hard-to-obtain 99% or so reflective aluminium sheet. Commonly available 90% stuff means that you are limited to very few bounces in the tube, meaning large diameters, and poor performance when the sun is low.

Thanks. Interesting stuff, but I'm thinking more of basic reflection between two points outdoors. A reflective dish on the wall throwing light on to another wall type of thing.

I want to make one of these:

david

Well, that's not really hard.

It's a few lines of code in a microcontroller, and a couple of large R/C servos, to point the mirror. The rest is just mechanics.

One way round the microcontroller is to have an axle, pointing to the north star, with a 24 hour rotation. Onto this, you attach a mirror, angled according to your latitude. This reflects the sun into the direction 180 degrees away from the north star, onto fixed mirror(s) that bounce it to the target. Wind, rain all make it fun.

Sounds like a piece of cake then :-) You got me wondering about the solar tubes as well. The problem with shade in a garden is that the light you need is often only the other side of a fence or wall, so a periscope arrangement might deliver enough light to at least prevent mould etc. Plenty to think about......

In Egypt, when you are inside the temples, it is a man with a mirror.

Colin Bignell

Hence the reasoning behind the invention of whitewash, a lime paste mixed with mutton fat. And might be part of the reasoning behind the heavy use of glass blocks in the last century?

You can't get the staff these days