Electricity supplied from the nation’s rooftop solar panels almost doubled last financial year, contributing to the slide in power demand from the grid and lowering carbon emissions, energy consultants Pitt & Sherry said.
In the year to June 30, solar photovoltaic panels supplied almost 2.7 terawatt-hours of electricity, up from 1.4 terawatt-hours a year earlier and 100 times the amount generated in 2008-09, said Hugh Saddler, principal consultant at Pitt & Sherry, citing Australian Energy Market Operator data. A terawatt is equal to 1 trillion watts.
While still only about 1.5 per cent of total energy supplied to the eastern Australian market, solar’s rapid spread comes at a time when overall demand for power is shrinking.
Last year the jump in solar power accounted for about a third of the reduction in output across the National Electricity Market (NEM) serving most of Queensland, NSW, Victoria, South Australia, the ACT and Tasmania. It’s “an important driver of the changes in the electricity market”, Dr Saddler said.
Power demand extended its decline into July, with annualised generation in the NEM sinking by 2.2 per cent, or more than 4 terawatt-hours, Pitt & Sherry’s monthly carbon emissions index, or Cedex, found.
As a result of falling output, carbon emissions from NEM generators were down 11 million tonnes at an annualised rate, or 6.3 per cent. About 60 per cent of the emissions drop results from a shift to less carbon-intensive fuels and the rest from weaker demand.
Coal squeeze
The retreating demand is one reason big generators EnergyAustralia and Origin Energy have been leading calls for the government’s Renewable Energy Target to be lowered. Under the current setting, the RET aims to deliver 41 terawatt-hours from large-scale clean energy sources such as wind, solar and hydro by 2020.
In July, the share of generation from coal, gas, wind and hydro was little changed on the previous month. Plants burning black or brown coal contributed about 71.3 per cent of the NEM’s power last year, the lowest share in decades.
The latest Cedex report also noted that expectations of rising seasonal summer demand peaks – a central rationale for spending billions of dollars on upgrading poles and wires – have failed to materialise.
Victoria’s highest peak came four years ago last summer, Queensland three years ago and two years earlier for SA and NSW.
Cooler summers do not appear to be the cause. Queensland’s peak day in 2011-12 was hotter than any since 1999-2000 yet demand topped out at lower levels than either of the two earlier years.
While the spread of solar PV has played a role in curbing peak demand, so has changing consumer behaviour and better energy efficiency, Pitt & Sherry said.
