1Calculate cost per kilometre
Use real-world efficiency and local fuel prices for both options. Avoid comparing claimed figures from different test conditions.
2Estimate break-even distance
If the CNG variant costs more, divide the extra purchase cost by the expected saving per kilometre to estimate break-even distance.
3Consider refuelling access
Long queues or a distant station add time and travel. Convenience has value, especially for low monthly usage.
4Review space and performance
Factory-fitted cylinders can reduce luggage space, and driving characteristics may differ. Test the exact model.
5Include maintenance and resale
Follow specified service and inspection requirements. Resale demand varies by location and vehicle condition.
Practical checklist
- Calculate both costs per km
- Estimate break-even distance
- Check nearby stations
- Inspect boot-space needs
- Compare complete ownership
Frequently asked questions
Is CNG always cheaper overall?
Not always. Low usage may not recover the higher purchase cost quickly.
Can I compare using claimed mileage?
Real-world figures provide a more useful estimate.
What is break-even distance?
It is the distance required for running-cost savings to recover the extra upfront cost.
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