The Light Fantastic 2

I just discovered this awesome web-based tool developed by NIWA ( National Institute for Water and Atmospheric Research ). It allows you to get a free estimate of how much sun energy/m² your house gets over a certain time period, to help to determine whether ( weather ) solar heat or electricity generation panels would be worthwile to install on your roof.

http://www.niwa.co.nz/our-services/online-services/solarview/solarviewexplanation

and the one for our flat: