Making a flat parabolic mirror

Regular parabolic mirrors are great for concentrating sunlight for solar heating, however they are bulky and can be difficult to repair. That’s where Dominic Wanjihias’ flat parabolic mirror comes into play. He replaced the traditional curved mirror with a series of thin strips of mirror, making what appears to be a Fresnel reflector. It’s a pretty simple concept, but has a bunch of practical advantages:

1. It is very cheap,
2. It can be quickly dismantled or moved,
3. It is easily transportable as it can be carried flat or in a tube,
4. It is easily repaired if broken as the individual mirror pieces can be replaced (rather than having to fix or replace an entire parabolic mirror).

It’s not mentioned in the article, but I assume that the individual pieces have to be bent into a curve shape to be able to focus light to a point. Anyone know for sure? [via afrigadget]