Hi Ray
There are a lot of options you could look at, such as low energy lighting (which would require a change to the lighting units) and motion sensors to switch the lights on as soon as there’s movement in the area that requires lighting. They are more efficient than timers and don’t cost that much these days.
The way most owners corps look at this is to calculate how long it would take to recoup the outlay for a new system. It might take a couple of years but I’ve heard of buildings making their money back in 18 months … after that it’s all “profit”.
Willoughby Council is holding a seminar on Thursday night (Sep 18) and you can find out more about that HERE. or you could have a look at this PDF produced by Julien Freed, the guest speaker at the Willoughby seminar
Willoughby is one of several Sydney councils that have got together to suggest reliable suppliers for solar power units and you can have a look HERE where there are links to firms that can give you expert advice.