It found an 83c difference in the average price of regular 91 fuel at the three stations on Waiheke compared with all stations in Auckland over the second quarter of 2024.
“We would expect prices on Waiheke to be higher because of the additional cost of transporting fuel via ferry,” the commission said.
“However, it was unclear how much of the approximately 80 cents per litre difference in prices between Waiheke and other Auckland stations was explained by this additional cost.”
It found the additional cost to supply fuel to Waiheke, particularly freight, accounted for less than one-third of the price difference compared with the mainland.
“While high prices alone are not evidence of anticompetitive conduct, in a competitive market we would expect prices to reflect the cost to supply fuel at the pump. This is not the case on Waiheke,” the commission said.
“Consequently, competition between the three retailers on Waiheke appears weaker than we would expect.”
The commission said Waiheke may be experiencing a more acute reduction in retail fuel demand than elsewhere in the country due to demographic trends and a shift towards electric vehicles.
“This can place upward pressure on prices as fuel retailers seek to recover fixed costs with declining revenues.”
Gaspy data supplied to Barrier Times showed the average petrol price gap between the island and Auckland had nearly doubled in the past six months.
The gap stood at $1.71 on September 13, up 91% compared with March 21.
Aotea Great Barrier Local Board chair Izzy Fordham told the Barrier Times the price increases would “cripple a lot of people”.
International oil prices have surged higher again on the back of the ongoing conflict between the US and Iran and a recent drone attack on a critical Saudi oil pipeline.
In Auckland, the average price of unleaded 91 has risen more than 30c a litre in the past two weeks, according to fuel tracking app Gaspy.
Today, unleaded 91 was sitting at about $3.37 a litre, up from $3.06 on September 11.
Meanwhile, unleaded 95 is up 53c a litre to $3.55 over the past 28 days.
Diesel has risen more than 57c to $3.11 in the past 28 days.
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