Frugal motoring

Petrol prices are on the rise and more people are now considering switching to electric vehicles. Each year the Inland Revenue Department calculates the cost per kilometre of operating a vehicle, which includes the fixed costs and depreciation and running costs.

The good news is that the cost of an electric vehicle has gone down 5 cents a km over the last year to 76 cents, but the cost of a conventional petrol vehicle is up 3 cents a km, also to 76 cents. The convergence of the costs has for the first time brought electric vehicles costs on a par with petrol.

It is highly likely that the running cost of electric vehicles will continue to come down, relative to petrol, as the production of electric vehicles increases and the price per unit falls. Given the simplicity of an electric engine, we believe there is potential for transport costs to be reduced significantly in the future. For most of us, the up-front cost of owning an electric is still too much of a hurdle so it looks like we will be still filling up at the petrol station for a while yet.

Paul has a tip for frugal motorists. “There is an app for mobile phones for this called ‘Gaspy’. It’s a kiwi bit of software using the GPS on your phone it shows the cheapest petrol stations near you and the distance from your current position to it.”

Gaspy is well worth a look if you want to get the best deal on 91, diesel, and 95 fuels. This is how they describe themselves: “The prices on Gaspy are crowd-sourced which means we rely on like-minded consumers to locate and share the best fuel prices in NZ for shared benefit. By working together we can all enjoy cheaper gas and put pressure on Big Oil to maintain competitive pricing.”

While the data does not come from service stations directly and may not include all outlets, a look around the site shows crowd-power is providing sufficient data to achieve the objective – which is to show users where they can buy the cheapest fuel. In the Bay of Plenty and Auckland areas, for example, they say savings typically are about 13 cents a litre. In Northland and the Waikato, it’s 10 cents.

It’s easy to use. Just put in the location you wish to search. The APP will then list the outlets ranked by price. Select the location and it will take you to Google maps to so the location. Click directions and the navigation will take you there. Simple. Money saved.

Not only is the APP great for those who want to save money, but also for those who want to do their bit to bring greater competition to the fuel retail industry. There is no question competition results in better pricing for the consumer, and that’s a great thing. Consumer power is market democracy in action.

We use the APP, and find it especially useful when we are visiting a town and we don’t already know where the best deals are, or filling the tank on a long trip. By thinking ahead a hundred kilometres or so, we can plan the pit stop and get the best economy from the refill. As a general rule, we have found Gull is typically the cheapest place to fuel-up – their self-service stations in particular.

While on the subject of fuel prices, something to think about when you are replacing your vehicle is the type of fuel it uses. Most cars run on 91 octane, but some run on the higher 95 octane fuel. These are generally higher performance cars with higher compression. There is no benefit in using 95 petrol in a car where the manufacturers recommend using 91.

The higher octane fuel costs anywhere between 10 and 20 cents more a litre, depending on where you shop. That’s significant money over the life of the vehicle. We recall the case of a motorist who was bragging about how frugal they were because they shop around for the lowest fuel. They were less effusive when it was pointed out that having a vehicle that ran on 95 octane fuel instead of 91 was adding at least 10 cents a litre to their fuel bill.

Did you know that tyre pressure affects fuel consumption because when under-inflated their rolling resistance increases? According to one tyre company, every 10% under the vehicle manufacturer’s recommended pressure costs about 2.5% in fuel consumption. So if a tyre is running at 27 PSI instead of 30 the extra fuel consumption will cost about six cents a litre based on today’s pump price. To find out what tyre pressures are recommended for your vehicle, go to, or look for a sticker in your car’s door jam – or check your owner’s manual. The recommended pressure for most cars is usually between 30 and 35 PSI.