The Australian Energy Market Operator has unveiled its summer readiness plan for 202-21, and for the first time in several years has predicted no supply shortfalls – although it remains wary of freak events and the lingering impact of Covid-19.
The prediction is all the more remarkable because this year’s forecast is based on the much tighter reliability standards, which is now set at 0.0006 per cent, compared to 0.002 in previous years. The highest level of unserved energy is Victoria with just 0.00034 per cent.
The principal reason for the improved situation is the addition of more than 5GW of wind and solar capacity.
“The NEM (National Electricity Market) is in a more positive supply-demand position heading into the 2020/21 summer, with no supply shortfalls in excess of the reliability standard projected,” AEMO’s chief operations officer Michael Gatt said.
“This is primarily driven by up to 3,400 megawatts (MW) of new wind and solar generation capacity added since last summer, along with generation units expected to complete their planned outages before Christmas,” he said. There is also an additional 2GW of rooftop solar added since the start of last summer that will also improve supply.
Still, the report acknowledges there will always be risks of extreme events – although it is more likely to be from cyclones and flooding this summer rather than bushfires, and equipment failure.
To guard against such risks, AEMO has attract more than 1,900 MW of additional reserves through the Reliability and Emergency Reserve Trader (RERT) panel function.
These will only be used only if the market does not respond with enough supply or demand resources to meet the reliability standard or manage power system security incidents, such as the loss of multiple generation or transmission assets. But the arrangements means that AMO will not commit to availability payments until and if they are actually needed.
Among the factors making AEMO’s task easier this summer are improved self-forecasting for wind and solar generators, greater visibility of virtual power plants, and closer collaboration with weather forcasters. It also believes it has a better handle on the unexpected high temperature wind de-ratings experienced last summer.
The joint self-forecasting initiative with the Australian Renewable Energy Agency has been successful, and as of early October 2020, 24 solar farms and nine wind farms in the NEM had been accredited for self-forecasting in dispatch. This had, on average, improved self-forecasts by about 16%.
- Grid demand remains something of a wild card because of the fundamental shifts in behaviour caused by the Covid-19 pandemic, and it is not certain how this will play out over the summer.
- AEMO will be using publicly available Google mobility data to track the extent to which underlying behavioural changes exist to try and better understand demand patterns and it has also shifted to more regular updates of installed rooftop solar capacity in the Australian Solar Forecasting System (ASEFS).