Hi All. Several others as well as myself have referred to the Clean Energy Council (CEC) PV System Design Guidelines document. This document has some very useful tables in the back, giving the expected PV system output for several major (Australian) cities for a range of panel orientations: both varying inclination and azimuth. They express the (annual) output as a percentage of that for a system with the panels tilted North at the angle of the latitude. There are also some really good explanations of the various losses and inefficiencies in a PV system, and worked examples of the calculations necessary in designing a PV system. To get the actual estimated system output, you can look up the Consumer Guide, with the link provided at the end of this post.
The CEC has been revamping its website, and accordingly, the links provided in previous posts have been broken. The correct link is not intuitively obvious. I had searched in "Resource Centre", but it is necessary to look under Accreditation, then through to Solar PV Accreditation (rather than Wind). There you may need to click the link to the new site. Once there, look under Installer Resources, and then Useful forms & checklists. From there, scroll down the page to Other useful information and checklists.
The Design Guidelines document is then listed second. You may like to have a look at the Grid-Connect Install & Supervise Guidelines - Issue 6 Sept 2010 document as well as that for Small Wind Design Guidelines CEC.
There is also a 28 page consumer guide. This document has some useful statistics on expected system outputs as well as advice for consumers who are considering buying a PV system.
Happy reading, and hopefully these guides will answer most of the queries people have about system orientations and outputs relative to rated output. c*p