Solar Fire

This looks quite neat, and would be especially suited for equatorial regions. The main limitations are that you need a water supply, and that in this case it looks as if the adjustment of the mirrors throughout the day is purely manual. There's nothing very high technology here, and systems like this could have been used to generate power at any time in the previous century or more.

It's also possible to obtain mirrored tape, so the mirrors could be made very cheaply using any common material such as plastic or wood for the backing.



There is some free software (GPL) available to calculate the mirror angles, and in principle this simulator could also be extended to include an estimate of power output given the current or average cloud cover. One of the problems with solar systems is being able to make an estimate of whether it would be capable of producing a usable amount of power at a particular location, and that's where a simulator could help in making investment decisions.

Of course this is likely to be a higher maintenance system than photovoltaics and batteries, but at current prices it's far cheaper than that. Cheap photovoltaic solar has been promised for many years, and so far hasn't materialised, but new ways of producing solar panels should mean that they eventually become the lowest cost and least maintenance solution.