Rooftop solar now 13% of residential demand in S-E Qld

Rooftop solar now provides 13 per cent of residential energy in south-east Queensland, and households with solar arrays are now producing the equivalent of more than half their electricity needs from solar.

New data released by Energex, the network operator that manages the distribution grid in Brisbane and the southern coastal regions, estimates that 90GWh was produced in the month of October by the 272,878 rooftop solar systems in the network.

This equates to roughly 13 per cent of the estimated 676GWh consumed by households in the same month. Given that less than one quarter of homes have rooftop solar, that means that those solar households are producing more than 50 per cent, on average, of their consumption.

Most of those soalr houses are exporting much of that solar back into the grid – particularly those on the favorable solar feed in tariffs – and then drawing from the grid when the panels are not producing. In October, around 70 per cent of total solar generated was fed back into the grid (66GWh) because of longer days and the fact that air conditioning was not yet in full swing.

But an increasing number of homes – 74,000, or 6 per cent of all residences, are not getting that tariff, so have an incentive to “self consume” to offset the cost of grid power. A total of 24GWh was “self consumed” during the month.

Interestingly, according to the Energex data, these homes tend to have larger systems, averaging around 4kW. That will probably give homes an incentive to install battery storage to maximize their “self consumption”. As we noted on Monday, investment bank UBS now suggests that this is economically viable in Australia under certain systems and conditions.

The Energex data says that another 2,630 homes signed up for rooftop solar in October, and another 800 homes fell off the solar bonus tariff because they changed hands.

Another 58 larger systems (5kW – 1MW) systems were connected. That means there are now 953 of these larger systems totalling 11 MW generating capacity now in service in south-east Queensland, although the state is being outpaced in the rate of commercial scale installation by South Australia and New South Wales, according to recent data.

South east Queensland now has a total of 895MW of rooftop solar. Of this, 269MW are “non-FiT” systems.