Rooftop solar most reliable source of new generation on NEM, says report

The installation of solar on Australian homes and businesses has made rooftop PV the most reliable source of growing generation on the National Electricity Market, a new report has found.

In its January 2018 issue of the NEEA Electricity Update – the companion publication to the National Energy Emissions Audit Report – The Australia Institute says a rooftop solar market that had more than doubled since 2013 delivered record total of 6.2TWh in the year to December 2017.

“Rooftop solar has been installed by over 1.6 million households and is the most reliable source of steadily growing generation in the NEM (see Figure 3, red line),” the report says.

“Steady growth in rooftop solar PV, contributed to net generation or ‘generation sent out’, being 5 per cent lower than in June 2008 (see Figure 1 below),” the report added.

The report also noted that overall changes in the mix of generation supplying the NEM had delivered a drop in average emissions intensity for the year, of 0.2 per cent, to 0.831 t CO2-e/MWh.

“Up to the end of November 2017, reduction in demand for electricity from the grid contributed about one-third of the total reduction in annual emissions from NEM generation since June 2008,” said the TAI report.

“The other two thirds were contributed by the lower average emissions intensity of electricity generation.”

You can see these generation mix changes, which have driven this fall in average emissions intensity, illustrated in Figures 2 (below) and 3 (above).

Note the rise in the emissions after the Coalition repealed the carbon price, and the fall in emissions since the closure of the Northern and the Hazelwood power generators, which it opposed

But the report stresses that the fall in the brown coal share of generation is almost entirely due to the closure of one of Australia’s most dirty power stations, Hazelwood, in March last year.

And this is more or less cancelled out by the increased share of both black coal and gas-fired generation, in NSW, Victoria and South Australia.

“Both these generation sources have much lower emissions intensity than Hazelwood, as Figure 4 shows, and consequently overall emissions intensity fell steadily,” the report says.

Renewable generation also fell, however, “as the earlier increase in hydro generation was reversed and wind generation stayed roughly constant.”

Figure 7 shows a breakdown of the annual renewable share of generation, with the steady growth in rooftop solar.