Tracking power prices across Australia is complex. The RepuTex report relied on by Labor refers to "an annual electricity bill for an average household".
Director of the Energy Program at the Grattan Institute Tony Wood told the promise tracker that average consumer electricity prices were published regularly by the Australian Competition and Consumer Commission in its Inquiry into the National Electricity Market reports.
Mr Wood noted the RepuTex modelling was based on a reduction of wholesale prices in the National Energy Market servicing Queensland, NSW, the ACT, Victoria, SA and Tasmania. The NEM does not service customers in WA or the NT.
The inquiry has been running since 2018. The ACCC publishes two series of reports, in recent years produced each May and each November.
A spokesman for the ACCC told the promise tracker that the two reporting cycles "draw from different datasets and there are a number of methodological reasons why estimates from the two approaches will differ".
The first series presents an analysis of electricity retailers' billing data.
The second presents an analysis of the cost components of electricity bills, which the ACCC calls a "cost stack" approach. "This can be considered a proxy for the annual amount that an average customer would pay for electricity," a recent ACCC report says.
There are timing differences between the two series of reports.
In addition, the billing data reports use figures for the median, or "typical", customer. The cost reports use figures for the average customer.
A spokesman for the ACCC said: "The primary driver of variation in bills is differing electricity consumption, so assuming median usage will broadly reflect the circumstances for the middle group of customers."
In its latest cost report, the ACCC notes: "The average customer uses more than the 'typical customer'. This is a result of a small number of customers with much higher than average electricity usage."
The promise tracker considers both series of reports to be useful in tracking changes in annual electricity bills for an average household.
Both sets of reports note the limitations of focussing on a single figure.
The latest billing report says there is "substantial variation in effective prices between regions" of the NEM.
The latest cost stack report says the figure presented for an average customer "is only a general representation due to significant variation in usage volumes between geographic regions, time periods and customer types."
The most recent ACCC report available when Labor's Powering Australia plan was released was for May 2021 using billing data.
It showed the median annual residential electricity bill for customers in all NEM regions in 2019-20 was $1,209.
Ten days after the Powering Australia plan was released, the ACCC published a report from its cost data series for November 2021 which contained much more recent figures.
This showed the average annual cost to supply electricity to a residential customer was $1,434 in 2020-21.
This promise will be delivered if, at the end of Labor's term, the annual NEM electricity bill for an average household has been reduced by $275, taking into account the ACCC and other sources, with prices adjusted for inflation to maintain the purchasing power of $275 in 2021 dollars.
Here's how the promise is tracking:
