A couple of points, many experts, including Christine Byrne of GreenStrata, believes you are better to first limit your excess usage of energy through a variety of simple cost-saving strategies, such as reducing lighting in garages and common areas, before you even look at the additional benefits from installing solar power.
Also, we don't necessarily endorse the company linked in the above posting – we've left the link there as a service to readers, but use your own judgement if you choose to pursue it.
It is not strata specific and I would prefer to link to a solar energy installer who had addressed and solved the many problems of strata installation – if, indeed, there is one out there.