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How would I find out about the real cost for CNG? It used to cost $8.50 to fill a 70 litre tank and now it costs me $23.75. The petrol station is charging $15.99/kg and its the only one here in Wanganui.

Why would the costs increase for CNG when it is not Petrol?


From the "Ask Jack" archives - 27 July 2010


The answer below is from our Senior Policy Analyst in Wellington Mark Stockdale. Mark and his team monitor fuel prices on a regular basis.

I'm afraid there isn't a lot of information on CNG. In fact, we understand there are less than a dozen service stations still supplying it.

The CNG price isn't related to international movements in crude oil or refined petrol prices (unlike LPG, which is), but we have been advised that the price of CNG has been rising due to diminishing supplies from the Maui well.

The old Maui price was fixed, but as CNG is now being sourced from other domestic wells, those prices will be set between the supplier and the gas distributor, and are higher.

I don't know how often that price is reviewed, but the price between the distributor and the retailer (service station) may also be increasing due to rising demand for CNG for electricity generation.

Certainly, the service station doesn't control the price. In Wanganui, CNG is supplied by Wanganui Gas, so they may be able to give you some idea why the retail cost has gone up.