Over the years, the Indian automotive industry has continuously evolved to meet the needs of car buyers. However, with recent advancements into EVs and Hybrid cars, older technologies such as Petrol and CNG cars have remained a mainstay for buyers, with car makers like Maruti Suzuki, Hyundai and even Tata actively offering CNG variants of their cars.
Government policies in recent years have also diminished the allure of buying a diesel vehicle, and buying an EV or strong hybrid vehicle is an expensive proposition not suited for budget car buyers. In such a scenario, CNG is looked upon as the economical choice of fuel, but how much more money do you actually save over a period of 5 years?
To find out the answer to which is the better option for you, we have put together this article highlighting the pros and cons of both.
Petrol vs CNG Cars: Cost of Purchase
When it comes to the upfront cost of petrol or CNG cars, they are both better off when compared to EVs and strong hybrids. However, when you compare them side by side, similar factory fitted CNG variants are priced roughly ₹ 1 lakh higher than their petrol counterparts.
This cost can be slightly lower for aftermarket CNG kits, however, the added warranty and seamless integration of factory fitted CNG kits far outweighs any cost advantage. To give you a better idea, we have chosen a few popular models to highlight the cost difference between their petrol and CNG variants.
| Model and Variant | Ex-Showroom Price of Petrol Variant | Ex-Showroom Price of CNG Variant | Difference |
| Tata Tiago XZ | ₹ 6.90 lakh | ₹ 7.90 lakh | ₹ 1 lakh |
| Hyundai Grand i10 Nios Sportz | ₹ 7.42 lakh | ₹ 8.38 lakh (Dual Tank) | ₹ 96,000 |
| Tata Tiago XZA (Automatic) | ₹ 7.45 lakh | ₹ 8.45 lakh | ₹ 1 lakh |
| Maruti Suzuki Swift ZXi | ₹ 8.29 lakh | ₹ 9.19 lakh | ₹ 90,000 |
| Nissan Magnite Tekna Plus | ₹ 9.27 lakh | ₹ 10.02 lakh | ₹ 75,000 |
| Tata Nexon Fearless Plus PS Dark | ₹ 13.50 lakh | ₹ 14.50 lakh | ₹ 1 lakh |
| Maruti Suzuki Ertiga ZXi (O) | ₹ 11.16 lakh | ₹ 12.11 lakh | ₹ 95,000 |
The higher initial cost of CNG vehicles is because of the additional components of the factory-fitted CNG kit. These include the cylinder tank for storing CNG, high-pressure lines from the tank to the engine, specialised injectors, and the necessary modifications to the engine control unit (ECU).
This initial difference in the cost of petrol and CNG variants can help consumers determine whether the long-term savings in running costs can offset the higher initial investment of a CNG car.
The long term savings in terms of lower running costs can make CNG cars more cost-effective for high-mileage users. One should consider their budget, driving habits, and long-term cost savings when deciding between a petrol or CNG car.
Petrol vs CNG Cars: Efficiency & Range
Over the years, petrol and CNG cars have both seen advancements in technology. Historically, CNG cars have always been more efficient, however, as such cars are fitted with additional tanks, their range is lower than what the same cars can achieve when running on petrol.
To give you a better idea, we have taken a few popular models and calculated their range on petrol and CNG, giving you an idea of their respective range. In the Indian car market, Maruti Suzuki is the only car maker that publishes ARAI figures for their cars, and thus we will be sticking to their models for this purpose. However, we have pickled cars from three different size classes to give you an idea of their efficiency and range.
| Model | Tank Capacity* | ARAI Mileage | Theoretical Range On One Tank |
| Maruti Suzuki Alto K10 | 27 litres | 24.38 km/l | 658 km |
| Maruti Suzuki Alto K10 CNG | 55 litres (water equivalent), 11 kg (gas equivalent) | 33.49 km/kg | 368 km |
| Maruti Suzuki Swift | 37 litres | 24.80 km/l | 918 km |
| Maruti Suzuki Swift CNG | 55 litres (water equivalent), 11 kg (gas equivalent) | 32.85 km/kg | 361 km |
| Maruti Suzuki Ertiga | 45 litres | 20.51 kmpl | 923 km |
| Maruti Suzuki Ertiga CNG | 60 litres (water equivalent), 12 kg (gas equivalent) | 26.11 km/kg | 313 km |
When we are speaking of outright range, petrol cars have a distinct advantage over CNG cars despite being less efficient. This is because the petrol tanks in cars can hold a lot more fuel compared to the kilograms of gas that can be stored in a CNG tank. Therefore, petrol cars offer a range of two to three times more than their CNG counterparts.
On the other other hand, CNG cars have an outright efficiency advantage over petrol, and are 25 to 40 percent more efficient. For example, the Alto K10 can travel 24.38 km on a single litre of petrol. On the other hand, it can travel for 33.49 km on 1 kilogram of CNG.
Furthermore, if we take a look at the cost of fuel as of June 2025, 1 litre of petrol costs ₹ 94.77 in Delhi whereas 1 kg of CNG costs ₹ 76.09. Therefore, not only is CNG more efficient, but it costs less as well. Keeping these figures in mind, let’s find out the running costs of both CNG and petrol.
For this calculation, we are going to consider an average yearly running of 12,000km and the fuel costs mentioned above.
Petrol vs CNG: 5-Year Running Cost
| Model | Annual Fuel Consumption | Annual Fuel Cost | Cost of Fuel Over 5 Years |
| Maruti Suzuki Alto K10 | 492 litres | ₹ 46,627 | ₹ 2,33,135 |
| Maruti Suzuki Alto K10 CNG | 358 kg | ₹ 27,240 | ₹ 1,36,200 |
| Maruti Suzuki Swift | 484 litres | ₹ 45,869 | ₹ 2,29,345 |
| Maruti Suzuki Swift CNG | 365 kg | ₹ 27,773 | ₹ 1,38,865 |
| Maruti Suzuki Ertiga | 585 litres | ₹ 55,440 | ₹ 2,77,200 |
| Maruti Suzuki Ertiga CNG | 460 kg | ₹ 35,001 | ₹ 1,75,005 |
As seen from the table above, the annual fuel cost for petrol models is significantly higher than their CNG counterparts. Furthermore, we already know that CNG cars cost about ₹ 1 lakh more than their petrol counterparts. So, essentially, it takes about 5 years for CNG cars to recover the initial additional cost of purchase.
Do keep in mind that the above calculations have been done using the fuel prices of Delhi and an average annual running of 12,000 km. Certain states such as Uttar Pradesh have a higher rate of CNG, and thus, the benefits will be lower. Alternatively, if your average running in a year is less than 12,000 km, once again, it will take you longer to recuperate the additional cost of a CNG car.
The vice versa is also true, meaning if the rate of CNG is lower and the average annual running is higher, you will recover the additional amount in a shorter amount of time. Ultimately, CNG cars become more cost effective over time.
Furthermore, as far as their maintenance is concerned, both cars undergo similar maintenance. However, CNG cars have a marginally higher maintenance cost due to the additional CNG kit testing every few years. Along with that, spark plugs also need to be replaced more often in CNG vehicles. However, over a period of 5 years, this cost turns out to be negligible.
What Should You Choose
Ultimately, picking between Petrol and CNG will come down to your driving needs.
You should choose a Petrol car if:
- You don’t drive daily or drive less than 8,000 km annually.
- You prefer the better performance of a petrol engine.
- You frequently drive on highways with the scarcity of CNG refuelling pumps.
- You use the boot often to store big pieces of luggage, especially if you frequently undertake road trips.
- You want to pay the least amount upfront for a car.
- You don’t want to go through the periodic maintenance checks for CNG.
You should choose a CNG car if:
- You drive long distances daily and have an annual commute of over 12,000 km.
- Your primary objective is lower running costs.
- You live in an urban environment with sufficient access to CNG pumps.
- You are environmentally conscious and wish to reduce your vehicle’s emissions.
- You don’t use your boot often and can do without storage space.
Picking between Petrol and CNG will come down to your driving preferences, routine, and budget. Petrol is better suited for those who prefer refinement and performance whereas CNG cars are better suited for budget and environmental conscious buyers.
FAQs about Petrol vs CNG
Q. Is it safe to drive a CNG car?
Yes, factory-fitted CNG cars are very safe. They undergo rigorous testing and adhere to strict safety standards. The CNG cylinders are designed to withstand high pressures, and safety features like leak detection systems and auto cut-off valves are integrated. Aftermarket kits, if not installed by certified professionals, might pose risks.
Q. Does CNG reduce engine life?
Generally, no. Modern factory-fitted CNG kits are designed to work seamlessly with the engine. While CNG burns hotter than petrol, engines are now engineered to handle this. Regular maintenance and proper servicing are key to ensuring the longevity of a CNG engine. Poorly tuned aftermarket kits can potentially affect engine life.
Q. Is the resale value of CNG cars good?
Yes, in cities and regions with good CNG infrastructure and high fuel prices, CNG cars often command a good resale value due to their lower running costs. Demand for pre-owned CNG vehicles is quite strong in these areas.
Q. Can I switch between petrol and CNG while driving?
Yes, modern factory-fitted CNG cars allow seamless switching between petrol and CNG modes, usually with a button on the dashboard. The car typically starts on petrol and automatically switches to CNG once the engine reaches an optimal temperature.
Q. Are there any performance differences between petrol and CNG?
Yes, CNG typically offers slightly lower power and torque output compared to petrol. This means a marginal drop in acceleration and outright performance, which might be noticeable during quick overtakes on highways or while climbing steep inclines. However, for city driving, the difference is often negligible.
Q. How much boot space is lost in a CNG car?
A significant amount of boot space is lost due to the placement of the large CNG cylinder. For a hatchback or compact sedan, this can mean almost all of the boot space is occupied, limiting luggage carrying capacity. Some MUVs or larger sedans might have better integration, but space is still compromised.
