A thread on why Sth Australia has the most expensive electricity on Australia’s NEM.
Short answer: because it has a very ‘peaky’ demand, driven by high electricity use in summer heatwaves. This in turn drives high network costs, particularly on the distribution network. (1/7)
Let’s look first at wholesale electricity prices.
SA has long had the highest prices on the NEM. Some claim this is due to its high wind & solar penetration, ~70% in 2022-23. But it had high prices long before RE made a meaningful contribution to SA’s electricity (RE<1% in 2007).
This is a good lesson on correlation does not equal causation. High electricity prices helped attract renewable developers to the state. ie. high prices caused high RE, not the other way round.
In turn, all the built RE helped alleviate those high prices (3/7)
OK, so SA has long had high wholesale electricity costs. What else is important?
The following figure shows that along with the previously discussed wholesale costs, distribution network costs represent an equally large component (4/7)
South Australia had a very large increase in distribution network costs between 2010/11 & 2013/14. As the AEMC noted at the time, this was driven by increases in peak demand caused by air-conditioner use during summer heatwaves (5/7)
But other Australian states are also subjected to high air conditioner load in summer. Is SA unusual in this regard? As the following chart indicates, yes SA is quite unique. It’s peak demand is over twice average demand, a much higher ratio than in the other states (6/7)
In summary, SA’s electricity price is higher than the other NEM states. This is due primarily to its peaky electricity demand driven by high air conditioner use during summer heat waves. This drives up its network costs, particularly for the distribution network (end)
One additional tweet. This article from 2018 also has some good analysis on why SA's electricity is expensive. In addition to what I mentioned, it also discusses SA's lack of cheap & nasty coal, no hydro & heavy reliance on gas. solarquotes.com.au/blog/south-aus…
One more tweet: SA has a lot of transmission network relative to its demand. That explains a lot of why its transmission costs are high, along with it 'peaky' demand profile. But as explained in tweet #3, transmission costs are substantially lower than distribution costs.
This article has an interesting discussion about why night-time off-peak rates can be cheaper than day-time, despite cheaper day-time wholesale prices. reneweconomy.com.au/im-buying-an-e…
The other states can learn from the ACT and how its Government has shielded its residents from electricity prices volatility:
What's better than a subsidy-free renewable project?
How about 2 subsidy-free wind farms that have returned over $6.5m to ACT electricity consumers since early 2023
/1
Back in 2020, the ACT Government signed contracts for difference (CfDs) with 2 wind farms, Berrybank & Goyder Sth. The CfD strike prices were $54.48 & $44.97/MWh respectively.
/2 reneweconomy.wpengine.com/act-secures-tw…
Here's how the CfD works. The wind farms sell their electricity on the spot market. If they sell it for less than the CfD price, then ACT consumers will top up the difference.
If they sell it for more, then the wind farms refund the extra to ACT consumers.
/3
Last week Aidan Morrison wrote a long thread criticising my weekly renewable simulations.
There were so many mistakes in Aidan's thread that it will take a long thread to address them all. Read along if you're interested.
/1
Aidan says that basically all the wind in the NEM during that period came from QLD.
That is false. QLD wind provided 40% of NEM wind over this period
/3
A thread on flexible generation on Australia's NEM.
Historically, flexible gas & hydro generators have complemented less flexible coal, to ensure supply can meet demand.
In the future, flexible generation will be dominated by batteries & they'll be also used to firm PV & wind.
/1
Demand is highly variable.
On the NEM average demand is ~24GW, but on a hot summer day, it can peak as high as 39GW.
Generators like coal (or nuclear) prefer to run at a near constant output, and are not suited to meeting these demand peaks.
/2
Historically, flexible gas & hydro generation has been used to meet these demand peaks.
Storage (batteries & pumped hydro) is also becoming a meaningful source of highly flexible supply.
As well as meeting demand peaks, flexible supply is also being used to firm wind & solar.
/3
Yes, if you add up all the annual costs in the ISP Step-Change scenario, you get to $692b (Real $2023). That includes $81b of emission costs.
That sounds a lot!
But what might a mostly nuclear scenario look like?
Short answer, it's likely to be much, much higher 1/n
If previously made a thread on what the LNP nuclear policy might look like.
It involves a lot of gas & a lot of emissions to fill the gap before nuclear starts, optimistically in 2040!
Thread: Each week I run a simulation of Australia’s main electricity grid using rescaled generation data to show that it can get very close to 100% renewable electricity with 24GW/120GWh of storage (5 hrs at av demand)
Results:
Last week: 100% RE
Last 167 weeks: 98.5% RE (1/n)
Last week had:
- below average demand (97% of long-term average)
- average wind (102%)
- well above average solar (125%) (2/n)
Here is the simulation from weeks 164 to 167. It was 100.0% renewable.
For earlier weeks, see the following thread (3/5)
There are good people advocating for nuclear in Australia.
Robert Parker isn't one of them.
He spreads misinformation about renewables & about the ISP.
His claims his proposed nuclear solution for the NEM is cheaper & cleaner than AEMO's ISP, but it is all based on lies.
/1
Robert claims his solution to be lower emissions compared to the ISP.
His solution has ~2,000 TWh of coal generation out to 2050.
The ISP has < 600 TWh.
The ISP has ~1/3 the total cumulative emissions out to 2050 compared to Robert's proposal.
/2
Robert claims the ISP emission intensity is 175g CO2/kWh in 2050.
That is a lie.
Full life-cycle emissions of the ISP are ~40g CO2/kWh in 2050, almost identical to what Robert's solution.
But Robert's would have 3x more cumulative emissions by 2050.
/3