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LPG vs Petrol Savings Calculator - LPG Average Mileage - LPG Conversion MPG

One of the biggest advantages of LPG vs petrol cars and vehicles is LPG average mileage (LPG mileage) cost, or LPG conversion MPG mileage cost, and the savings realised on LPG fuel consumption costs. 

LPG conversion MPG mileage (LPG average mileage) is the safe, inexpensive way to run your car, especially as the family budget seems to get more and more stretched!

Please use the calculator below to estimate your LPG average mileage (LPG mileage) LPG fuel consumption cost savings

Just insert the number of kilometres you drive your car per year and the LPG fuel consumption cost vs petrol in your area:


How to Beat the Petrol Price Cycle

Don’t you just hate having to fill up your tank in a week when the petrol and diesel prices are high? 

Think how much you could save each year if you could always time your purchases for the lowest priced days. 

There is a way!

LPG conversionsIf you are like me, driving a considerable distance every week, you frequently find yourself in a position where you need to purchase petrol or diesel while prices are at the high point of the price cycle. 

A few years back, when the price cycle was just one week, most people had the cruising range, on a single tankful, to make it through. 

Now the price cycle can be over 2 weeks long, exceeding the length of time you can go between fill-ups.

LPG Gas Conversion Cost - Dual Fuel is the Answer with LPG Average Mileage (LPG Mileage)

One of the unheralded benefits of having a dual fuel vehicle is the extended driving range provided by having two fuel tanks with LPG average mileage (LPG mileage). 

With both the petrol and LPG tanks filled, cruising LPG average mileage (LPG mileage) ranges of 1000km or more are not unusual.

So, unless you drive an extraordinary number of kilometres every week, you can cruise from low price point to low price point with a dual fuel car or truck LPG average mileage (LPG mileage), without having to refill in between.

Almost all vehicles fuelled by unleaded petrol can be converted to LPG operation at a reasonable cost. 

These dual-fuel LPG systems allow a vehicle to operate on either LPG or petrol and can frequently double a vehicle's mileage range with LPG average mileage (LPG mileage) and LPG price (cost) per litre. 

The petrol tank still remains in the car and the driver can switch from gas to petrol or vice-versa.

LPG Installation Cost

How much an LPG installation costs depends on the model and engine. How much to convert a car to LPG or the LPG installation price-cost also varies based on the type of LPG engine conversion system selected. An LPG installation price can range from around $2,500 to over $4,000 for LPDI models.

Converter-and-mixer systems have the least expensive LPG conversion cost whilst Liquid Phase Direct Injection (LPDI) are the most costly.

LPG Conversion MPG - LPG Average Mileage (LPG Mileage) - LPG Price (Cost) per Litre

LPG conversion MPG (LPG average mileage) is affected by many things including the efficiency of the engine, LPG fuel consumption, LPG price (cost) per litre, weight of the vehicle, gear ratios, average trip speed, driving style, traffic density, LPG average mileage (LPG mileage) and delays.

The percentages of Propane and Butane in the LPG also matter, but the LPG average mileage (LPG mileage) differences would be small.

With the exception of the percentages of the gas mixture, the remaining LPG average mileage (LPG mileage) items are the same regardless of whether you are running the vehicle with LPG or petrol.

LPG Average Mileage - LPG Mileage

LPG average mileage (LPG mileage), LPG Conversion MPG mileage or KM/L are measures of fuel efficiency. But LPG average mileage (LPG mileage) only tells part of the story. There is also a huge price difference between LPG price (cost) per litre vs petrol. What you really need to know is the LPG average mileage (LPG mileage) LPG fuel consumption cost and LPG price (cost) per litre vs the petrol average mileage cost, expressed in dollars per 100km.

This LPG average mileage (LPG mileage) cost is shown below. The dollars per 100km numbers are from a hybrid real world LPG mileage test.

LPG average mileage - LPG mileage

Individual results may vary based on driving habits, LPG price per litre, LPG mileage and driving conditions.

As explained above, each vehicle could have different LPG average mileage (LPG mileage) fuel efficiency.

In general, an LPG vs petrol car will have about 20% more LPG fuel consumption (LPG average mileage), by volume.  However, LPG price (cost) per litre is typically much cheaper.

Assuming that the LPG price (cost) per litre is about half that of petrol, the LPG average mileage (LPG mileage) LPG fuel consumption savings still amount to about 40%.

It is important to note that whilst LPG average mileage is expressed in miles per gallon, metric efficiency is usually measured and expressed in litres per 100 km (LPG mileage).

LPG Price (Cost) per Litre

LPG price per litre is still less than petrolThe LPG price (cost) per litre is still typically 50 cents to 65 cents per litre less than petrol. LPG price (cost) per litre also doesn’t bounce up and down, like petrol and diesel, with the weekly price cycle. 

Somewhere along the way, Australians forgot about LPG, even though the LPG price (cost) per litre is less than petrol. LPG price (cost) per litre is just much more stable, when compared to petrol pricing.

LPG conversion MPG mileage (LPG average mileage) typically results in hundreds, if not thousands of dollars of savings every year, depending on your vehicle LPG fuel consumption usage (LPG mileage) and LPG price (cost) per litre. 

This LPG average mileage (LPG mileage) number could be even higher if you factor in avoiding the purchase of petrol during the high priced days of the cycle.

Dual Fuel Conversion

LPG conversion technology has come a long way in the last few years. 

Liquid LPG injection offers advantages over older vapour injection systems.

A vehicle with a state-of-the-art liquid LPG system produces at least the same amount of power when running on LPG, as compared with running on petrol.

There are over 100 engineered Liquid LPG Kits for domestic and imported cars available from a number of Australian suppliers. 

There are also many specialist installers around the country who can install these kits on your car. 

The time required to install an LPG system varies. 

A typical family sedan, with a single boot-mounted tank, should take only one to two days.  

A large four-wheel drive, with multiple tanks, might take two to three days.


Calculator Assumptions:

LPG fuel consumption costs based on LPG average mileage (LPG mileage) figures for Falcon XT petrol sedan of 9.9L/100km and Falcon XT EcoLPi sedan of 12.3L/100km (both tested to ADR81/02, combined cycle). 

Data sourced from Ford Australia. 

Actual LPG fuel consumption and LPG conversion MPG mileage (LPG average mileage) savings will differ by vehicle and LPG price per litre.



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