This graph caught our eye. It comes from the most recent publication from the Australian Energy Market Operator, in this case an analysis of the high level of renewable energy penetration in South Australia, and its integration into the electricity market.
This graph gives an update of the amount of renewable energy installed in the National Electricity Market, which includes most of the eastern and southern states, but not isolated pockets such as Mt Isa, off grid areas, the Northern Territory and Western Australia. It is current up to the end of August, 2014 (although it doesn’t include biomass).
As RenewEconomy has noted on many occasions, South Australia has the highest level of variable renewable energy in Australia – quite possibly the world (in major economies), with an average 43 per cent wind generation in July, and days in September when wind and solar provided all of the state’s electricity demand, and more.
The AEMO study says that the SA power system can operate securely and reliably with a high percentage of wind and PV generation, including in situations where wind generation comprises more than 100 per cent of SA demand, as long as one of the following two key factors apply:
a) The Heywood Interconnector linking SA and Victoria is operational.
b) Sufficient synchronous generation is connected and operating on the SA power system.
The AEMO study notes that South Australia already has the highest wind and PV generator penetration of any NEM region. As the graph shows, it has 1,470 MW of installed wind generation and 540 MW of PV generation. This represents about 50 per cent and 17 per cent of total installed wind and PV capacity in the NEM respectively.
In terms of residential rooftop PV installations, SA leads the NEM with a penetration rate of almost one in four of all rooftops. And the rate of penetration is likely to grow: the AEMO says that under favourable market and policy scenarios, it is projected that at least 1,000 MW of wind and 500 MW of PV capacity will be added in SA by 2020 – doubling the amount of rooftop solar, and lifting the amount of wind by two-thirds.
The AEMO notes that these developments are a “benefit” to both SA and the NEM. But it also underlines the importance of a strong interconnector with the rest of the NEM – for obvious reasons. Without it, the state would have issues with the required controls to ensure system security. (The report does not address this issue, but Germany is rolling out battery technologies that assume the role of “synchronous” generators and could usurp the primacy of fossil fuel generation. AEMO says the chance of a disconnection is so low is it rated as a “non-credible” event – but just in case ….