South Australia’s electricity needs were met by 100 per cent renewables for an entire working day last week through a combination of rooftop solar and wind farms.
Between 9.30 and 6pm on Tuesday, September 30, a day not unlike most Tuesdays, with business and homes using electricity as usual, the state received the favourable weather conditions allowing solar and wind infrastructure to work side by side to achieve the impressive achievement.
Pitt & Sherry produced the data as part of the group’s Carbon Emissions Index (CEDEX) electricity overview. The report’s author, Hugh Saddler noted that during September 27 and 28, several wind generation peaks were experienced where wind supply was greater than the state’s National Electricity Market (NEM) demand.
South Australia has almost half of the Australia’s wind capacity, as well as one of the highest uptakes of residential rooftop solar, with 25 per cent of households having rooftop solar installations.
The Pitt & Sherry report identified that on the 30th, that the “true” demand by consumers (the amount of electricity being used by consumers), was in fact considerably higher than NEM demand – up to 20 per cent according to the Australian Photovoltaic Institute – because of the contribution of rooftop solar to total electricity supply.
During the period using 100 per cent renewables, all of the state’s thermal power stations were shut down, with the exception of the two units at the coal fired Norther Power station and one of the four units at the gas fired Torrens Island B station, with gas and coal fired electricity exported to Victoria, leaving South Australia operating on 100 per cent renewable energy.
In the report, Pitt & Sherry noted a graph showing the impact from wind generation on the pool prices in South Australia and Victoria from September 27 to October 1 which shows interaction between pool prices and wind generation. As Hugh Saddler puts it, “The inverse relationship between wind generation and pool prices is very clear – the more wind generation, the lower the price, on average.”