Solar reducing midday grid demand

This is especially apropos given the discussion lately about the enormous investment in electricity infrastructure just to cope with those few-times-a-year demand peaks - apparently usually in the middle of very hot days due to aircon use:

The recent take-up of domestic solar photo-voltaic (PV) panels in Australia has been quite phenomenal. Across 2010 and 2011, the installed capacity increased seven fold to about 1.4 gigawatts, doubling every 9 months. 

By the end of this year we will probably have in excess of 2 gigawatts of solar PV capacity installed. All fired up at the same time it is enough to produce about 8% of the average daytime electricity demand. 

... 

Since solar PV production rises and falls in a characteristic pattern through the daylight hours, any substantive impact should be evident in a distinct reduction in demand for mains electricity in the middle of the day... 

...the PV signature is blindingly obvious, especially in the states of South Australia and Queensland where PV penetration is highest. It is also showing itself in the revenues generated by electricity sold on the wholesale market. 

In South Australia, midday to early afternoon demand was down over the financial year 2011-12 by about 8% on the average for the period spanning mid- 2007 through mid-2009. That contrasted with a negligible change in demand outside daylight hours.