Diesel prices tracked well above petrol prices in the December 2022 quarter. Photo: NHVR

PETROL prices increased slightly and diesel prices remained significantly higher than petrol prices in the December quarter 2022, according to the ACCC’s latest quarterly petrol monitoring report.

Quarterly average retail petrol prices in the five largest cities (Sydney, Melbourne, Brisbane, Adelaide and Perth) were 182.7 cents per litre, an increase of 5c/l from the September quarter 2022.

Average retail diesel prices were 222.9c/l in the quarter, more than 40c higher than average petrol prices.

“Our report shows a range of international factors contributed to higher retail diesel prices in Australia,” ACCC chair Gina Cass-Gottlieb said.

“The small increase in average retail petrol prices in the major cities reflects the increase in taxes following the restoration of the full rate of excise from 29 September 2022, offset by a decline in international petrol prices.”

Global prices to blame

The report shows retail diesel prices continued to exceed petrol prices in the quarter due to the higher international refined-diesel prices since the Russian invasion of Ukraine.

Monthly average prices in cents per litre for Gasoil 10ppm and Mogas 95 in nominal terms: January 2020 to December 2022. ACCC calculations based on data from Argus Media and the Reserve Bank of Australia. The shaded area represents the December quarter 2022. The green dotted line indicates when the Russian invasion of Ukraine began on February 20, 2022. Source: ACCC

Reduced supplies of diesel from Russia, and from France due to refinery strikes, combined with increased demand for heating in the northern hemisphere winter kept diesel prices high.

Retail fuel prices in Australia are largely determined by international refined fuel prices, which are influenced by international crude oil prices, and the AUD-USD exchange rate.

The following chart shows average international refined diesel prices (Gasoil 10 ppm prices) and international refined petrol prices (Mogas 95), in Australian cents per litre.

“Russia’s invasion of Ukraine led to international diesel prices moving higher than petrol in early 2022. While international refined fuel prices reduced in the December quarter, the difference between the diesel and petrol benchmarks continued,” Ms Cass-Gottlieb said.

The increase in average petrol prices largely reflected the restoration of full excise

Petrol and diesel excise was halved in March 2022; when the excise cut ceased on September 29, the rate of excise increased from 23c/l to 46c/l.

Source: ACCC