solarisation

As the treasurer of a small but proud housing co-op, one that is thriving under new financial arrangements with our government funding body, I've actually been having sleepless nights imagining our future and the possible complete solarisation of all our houses - some 21 by the end of next financial year - over the next five years or so. Others in the co-op are equally excited, but I have to admit that I for one have only a vague idea what solarisation means. There's a part of me that treats it as an all-transforming magic; no more aircons, no more electric lights, no more heaters, no more anything electrical - we have solar.
So now I'm going to educate myself as to how domestic solar energy works, how much it's likely to cost and how it will benefit the co-op.
First, as this site informs us, there are two types of solar panel currently on the market, which use quite different technologies. They are the solar water heating panels, used simply to heat water, and the solar electric or photovoltaic panels which transform solar radiation directly into energy. It's the latter, of course, that this post is concerned with.
This Australian site provides a comprehensive guide to photovoltaic ''modules'', their types, their siting and installation and their output, but is silent on costs. Further, it says that ''with a few solar modules, the homeowner can capture some of [the sun's] abundant energy''. A few? Just how many are needed to power a house such as mine twenty four hours a day?
Clearly this will depend not only on the number of solar modules but their type. There are two main types currently on the market, crystalline silicon and amorphous silicon thin film. The latter technology is likely to lead to lower cost modules in future, and is a more flexible technology in general, though thin film modules are currently less efficient than crystalline silicon modules. With the further development of thin film modules, greater integration into building materials is expected.
Another factor is, of course, sunlight in your area. Adelaide gets more hours of sunlight per day, on average, than Sydney, and more still than Melbourne, but Perth gets more than any of the other capitals. Panels ideally should face north, and having enough north-facing roof-space on our dwellings could be an issue.
Another major factor is consumer usage, which varies considerably between households. Energy conservation still needs to be promoted throughout the co-op, regardless of solarisation.
It’s quite difficult to get clear information on cost, but I did read somewhere of an array of panels at a cost of $18,000 reducing electricity costs by about a third – or maybe it was two thirds. In any case, this sort of return may not be worth the cost to our co-op, especially as federal government rebates of up to $8000 per installation are not currently available to us, under the rationale that, as a taxpayer-subsidised organisation, we shouldn’t be eligible for further subsidies.

This is an issue we could lobby government on. There’s also an organisation called Solar Sales, based in WA, which provides consultancy for PV module installation, and helps in accessing government grants and rebates.

So, that's a start, but we have a long long way to go in terms of solarisation of our properties. It will probably be impossible, for example, to equally spread the savings among co-op households, as some homes would be able to accommodate more panels than others. It may be, though, that we could do two modules per home, to spread the load more evenly, and then add panels as we become more financial - but this would perhaps unnecessarily increase installation costs. Clearly we'd need advice tailored to our particular homes.