Welcome to the March 2020 issue of the NEEA Report, with data updated to the end of February 2019. Data presented covers electricity demand, electricity supply, and electricity generation emissions in the National Electricity Market (NEM), plus electricity demand in the South West Interconnected System (SWIS). The main trends in the mix of generation and the level of demand for electricity have continued as in the past two or three months.

The remainder of this issue focuses specifically on electricity supply and demand in South Australia. It looks at monthly demand for electricity supplied from the grid in the state and the changes in the mix of generation within the state and the balance of imports and exports through the interconnectors to Victoria over the past five years. It then shows exactly the same data, but with the addition to both supply and demand of electricity generated from rooftop and other small solar installations, embedded in the state’s distribution network, and not connected to the transmission grid or participating in the wholesale electricity market. As is well known, South Australia has a larger share of supply from rooftop solar, relative to total consumption of electricity. More than any of the other four states in the NEM.

The report then looks in detail at changes in the mix of supply sources in South Australia during January and February 2020, showing the changes in the mix of generation which occurred following the loss of the major Heywood interconnector linking South Australia and Victoria, which occurred on 31 January, when the key transmission line was blown down in western Victoria.

An interesting feature of electricity consumption in South Australia during February 2020 was that it was significantly lower than in February 2019. Careful analysis shows that this was not related to the loss of the connection to Victoria and the rest of the NEM, but was a consequence of weather during February 2020 which was, on average, considerably less hot than in February 2019. This provides an opportunity to examine in detail how extremely sensitive electricity demand in South Australia is to the occurrence of very hot days in summer, and to consider the implications of this sensitivity to the future evolution of electricity supply in the state.