The average daily energy consumption in SA is around 36,000 MWh (that's a power demand of about 1,500 MW).
The flat top to the combined wind and utility-scale solar power generation in the graph on the right shows that the generation from these two sources is being limited to about 1,300 MW; another indication that renewable energy generation capacity is going to waste at present in SA.
|Curtailment of wind+utility-scale solar in SA
|This graph shows that wind plus utility-scale solar (green and dark yellow) are being curtailed to a maximum of 1,300 MW.|
The graph covers the period 2020/04/26 to 2020/05/03. Source Open NEM
A third power interconnector (transmission line between states) has been proposed; this time between SA and NSW.
Its intended capacity is 800 MW and expected cost $1.5 billion.
Half a dozen or so
pumped hydro power stations have been
proposed in SA.
To the present none of these has reached financial close.
Their total energy storage capacity, if built, would be at least 6,000 MWh.
(Pumped hydro is probably a better fit for
Tasmania with its existing well developed hydro power and lower evaporation rates. It will require more interstate transmission interconnectors.)
Compressed air energy storage (CAES) is another technology that is being developed.
See, for example,
Hydrostor's Angas Project, apparently under construction a couple hundred kilometres from my home.
CAES seems to have much the same advantages and disadvantages as does pumped hydro energy storage, although the round trip efficiency of the former is about 60% while that of the latter can be up to 80%.
More lithium battery capacity can, and most likely will, be built.
Flow batteries are an alternative to lithium batteries for some applications and seem to be more environmentally friendly.
Some excess renewably generated power could be used to produce
hydrogen which has a number of uses including the production of ammonia, a substance in high demand around the world and that is easily exported.
At present 'green hydrogen', hydrogen produced using renewable energy to electrolytically break water into hydrogen and oxygen, is not economically competitive with hydrogen produced by using fossil fuel energy, but the price is rapidly dropping.
There are several pilot plants under construction in the state.
Demand response is another factor in the mix; encourage the use of more power when there is plenty of generation by low retail prices, encourage less use when there is a shortage by high retail prices.
It is being used to a small extent already, but there is potential for much more.
Anything the has some flexibility in time of use can be involved: storage water heaters are an obvious candidate, electric vehicle charging is another, then there's at least some short-term flexibility in air conditioning and refrigeration.
On the industrial scale is aluminium smelting (there are no aluminium smelters in SA but there is one close to the Victorian end of the Heywood Interconnector) and possibly desalination (the Adelaide desalination plant produced 4925 Ml of water in April 2020 and, I calculated, used around 25 MW of power).