In this section I have outlined the changes that are in the process of happening or seem very close to happening.
I've listed the more speculative and exciting developments in the
game-changer section and some of the
technical challenges below.
There are a great many rooftop solar PV installations in SA, typically no bigger than 5 kW and rarely bigger than 100 kW; there is scope for far more.
|Peterborough 4.9 MW Solar Farm
Photo taken using my drone, 2018/05/12.|
Peterborough township in the background.
The solar farm had not long been completed.
At the time of writing a number of utility-scale solar PV farms were either under construction or proposed in South Australia, some of these were in excess of 100 MW.
A 50 MW solar farm was proposed for the Snowtown Wind Farm (it was expected that the generation from the solar farm during daylight would smooth the total generation because the wind farm tended to generate most power at night).
It seemed likely that any new wind farm would include a significant solar PV component (and battery).
Just one of the more interesting solar developments happening at the time of writing was
Solar River Project, stage 1 being 200 MW solar with a 120 MWh battery, expected to come on-line in late 2019; stage 2 another 200 MW solar with a 150 MWh battery, construction expected to start in late 2019.
There are others of similar sizes proposed for Mintaro, Whyalla and Tailem Bend; and the Bungama Solar Farm at Port Augusta was near completion of the first of two stages.
At the time of writing
Sundrop Farms, near Port Augusta in South Australia (photo on the right) was the only significant development of solar thermal power with energy storage in the country.
It is not used to generate grid electricity, it powers a huge greenhouse including desalination of the very salty water supply.
|Sundrop Farms – the solar power installation
A small part of the greenhouse is just visible on the lower right.|
Heat is stored in molten salt in the large tank on the right behind the tower.
Photo taken with my drone
If substantially more renewable energy is to be installed in South Australia then at least one of four or more things must take place:
- There must be increased interconnection with the eastern states;
- There must be greatly increased amounts of energy storage installed;
- More uses for renewably generated electricity, such as hydrogen production, must be found;
- Wind farms and/or solar farms must be curtailed; that is limited in the amount of electricity they are allowed to generate.
Plainly this is a very undesirable option from both an emissions and economic point of view.
More renewable power to come, more need for increased interconnection, energy storage or energy consumption
At the time of writing (February 2019) there were two wind farms under construction in SA, Lincoln Gap (212 MW) and Willogoleche (119 MW).
There was also around a gigawatt of utility scale solar PV either under construction or in the pipeline.
Construction was expected to start within a few months on the 150 MW
Aurora solar thermal power station at Port Augusta which will include 1,100 MWh of energy storage (equal to eight hours of full load).
Should Aurora prove to be financially viable, more such installations could easily be built.
At the time of writing two wind farms were under construction in SA
(Lincoln Gap and
Willogoleche), it was looking like construction would start before long on the big
Port Augusta Renewable Energy Park (wind and solar) and planning permission was hoped for with the innovative
Crystal Brook Energy Park (wind, solar PV, battery, possible hydrogen).
Several other wind farms had been proposed.
At the time of writing there were two interconnectors between South Australia and the remainder of the NEM (National Electricity Market), both connected with the Victorian grid.
This section added 2019/02/15
So the maximum amount of power that SA could export with these two interconnectors was 870 MW.
(Just in the week prior to writing this section, that is from 2019/02/08 to 2019/02/15, there were four quite separate occasions when the amount of power being exported from SA was above 600 MW and four occasions when imported power reached over 400 MW.)
- The capacity of the Heywood Interconnector was increased from 460 MW to 650 MW in mid 2016.
- The Murraylink direct current link has a capacity of 220 MW.
In February 2019 transmission network companies ElectraNet and Transgrid delivered their final report into their proposal to build a $1.5 billion link between Robertstown in South Australia and Wagga Wagga in NSW. They have dubbed the project “EnergyConnect”.
For more information on the proposal see
This will be a boost for the renewable energy industry in both states, but particularly for SA, and consequently help to reduce Australia's greenhouse gas emissions.
It is proposed that the new interconnector will have a capacity of 800 MW, which is about a half of the typical electricity generation in South Australia.
At the time of writing there was increasingly often more renewable energy generation in SA than could be used in the state or exported via the existing interconnectors to Victoria.
AEMO's Quarterly Energy Dynamics report for the forth quarter of 2018 stated that:
"Curtailments of non-synchronous (wind) generation in South Australia amounted to 4% of available generation for the quarter, down from 10% in Q3 2018."
This amounts to a substantial loss of earning power as well as being a loss of clean energy that could go toward displacing fossil fuelled power and reducing emissions, and it will only increase as more renewable energy comes on line.
The new interconnector will allow increased wind and solar development in SA because any excess, beyond local consumption, will be able to be sent to NSW, displacing coal power there.
There are times when there is wind in SA and not in NSW (and vice-versa), so the new connector will allow one state to help out the other at these times.
Solar power generation in SA peaks later (often an hour or more later), and continues later in the day, than in NSW.
Often the peak demand on the NSW power grid comes when solar power in SA is still generating substantial amounts of electricity; the new interconnector will allow this to be sent to the east.
Energy stored in one state will more readily be able to be used in the other state, when needed.
It is expected that the interconnector will be completed about 2022.
In the long term, as fossil fuelled power generation is phased out, high capacity energy storage facilities will be needed; at the time of writing, early 2019, it seems unlikely that batteries will be able to provide this capacity.
Several pumped hydro schemes have been proposed, many more are needed.
Two that seem likely to be built in the near future are
Goat Hill, 220-270 MW, 1.8 GWh and
Baroota (photo in the
Potential section and mentioned above), 200-270 MW, 1.6 GWh.
Both of these are in the upper Spencer Gulf area.
For comparison the Hornsdale Power Reserve, the biggest battery in the world when built, has a capacity of 100 MW, 0.129 GWh.
A low wind period lasting a couple of days can leave an energy short-fall of 30 GWh, so plainly far more energy storage than will be provided by these two projects would be useful.
(By comparison the Energy Connect interconnector discussed above could deliver 19 GWh in a day.)
Another factor that must be considered is that batteries and pumped hydro will be most economically viable if they cycle once a day.
Whether they can be economically justified if only used once a week is questionable.
My impression is that high-capacity long-distance interconnectors will be needed for at least the foreseeable future.
'Virtual' power plants
At the time of writing several pilot projects were underway testing the practicality of integrating household batteries and household solar into the state power grid.
The expectation was that this could add flexibility in matching generation to consumption.
In September 2018 the SA (Liberal!) government was aiming at building
the world's largest virtual power plant that would eventually include a total of 50,000 houses, 250 MW of solar power and 250 MW/675 MWh of battery storage.
At least until various forms of energy storage (such as
pumped hydro) can fill in the generation gaps from renewables we will need peaking power, which currently means gas-fired generation, but there seems to be no need of more in the foreseeable future.
With the current growth in renewables and energy storage there is absolutely no need for new base-load (coal or nuclear) power in South Australia (or, for that matter, in Australia).
I have discussed the
myth of base-load elsewhere.
In-situ gasification (ISG) has been trialled at Leigh Creek in the Northern Flinders Ranges (in the same coal beds that were used to supply the Port Augusta power stations).
In terms of carbon intensity (the amount of carbon dioxide released per unit of useful energy obtained) ISG is
worse even than mining and burning coal.
It is the least attractive option for producing energy from the point of view of greenhouse emissions minimisation.
With ISG the coal is partially burned underground, releasing carbon dioxide, carbon monoxide, methane and hydrogen.
Later the carbon monoxide, methane and hydrogen are burned to obtain useful energy, releasing more carbon dioxide, and steam.
Another major risk of the process is that some of the methane generated in the coal seam is likely to leak into the atmosphere.
Methane is a very active greenhouse gas, far more active than carbon dioxide.
It would be a serious backward step, ethically and environmentally, for ISG to be used in South Australia's energy future.
On the point of reliability,
AEMO's Electricity Statement of Opportunities, September 2017 forecast "From 2018–19 to 2021–22, progressively decreasing levels of
potential USE [Unserved Energy - power failures due to insufficient generation] conditions are observed over the next four summers, due to increasing renewable generation." The AEMO report foresaw the highest chance of a USE event happening in financial year 2017/18. There were none in SA in that period.