Many of us are confused does air conditioning use petrol or not. The answer is yes, they do. But how much it affects your petrol bill depends on various factors. The aircon works using a compressor, and that compressor runs off the engine. So when you switch the AC on, the engine has to work a bit harder and that means it uses more petrol.
Now, how much more? For most cars, it’s somewhere between 3% and 10%. If the car’s older or the AC hasn’t been maintained well, that number can shoot up to 20%. And here’s something many drivers miss, idling with the AC on can be worse. Now you must be wondering, how much fuel does car ac consume in 1 hour?
So, just sitting with the engine running and AC blowing can burn about 0.2 to 0.4 litres of fuel every hour.
If the system hasn’t been checked in a while, like if the refrigerant is low or the filters are clogged, the compressor has to push even harder. That puts more load on the engine and ends up burning even more fuel. This blog aims to answer all the questions regarding car air conditioning and the use of petrol.
Also Read: Why Does My Car Air Conditioning Smell?
Does Air Con Use Petrol While Driving or Standing Still?
How much petrol consumed when ac on in standing car is a frequently asked question. If you’re cruising on the highway or just sitting with the engine on, the outcome isn’t the same.
While driving, turning on the air conditioning puts extra load on the engine, but it’s usually more manageable at higher speeds. Since the engine is already working harder during movement, the fuel efficiency dip may not feel as steep. You’ll still use more petrol, of course, but it’s not excessive unless you’re constantly switching AC to max.
Now, when you’re stuck in traffic or waiting with the engine running, it’s a bit of a fuel trap. The AC still runs, the compressor stays active, but your car isn’t moving. Which means you’re burning fuel without going anywhere. That’s when people start to notice fuel disappearing faster than usual. You could be losing 0.2 to 0.4 litres per hour in that kind of idle state.
And here’s another thing, if your AC system isn’t in good shape, the impact on petrol gets worse. Let’s say the refrigerant is low, or the compressor’s straining, or filters haven’t been changed in a while. In all those cases, the system needs more energy to cool the cabin, which means more engine power, and therefore more fuel.
Newer cars have some efficiency features built in, like smart climate systems that regulate how long the compressor stays on. But older models tend to run the AC full-time once it’s switched on, which can be rough on mileage. This would answer your question of does air conditioning use fuel in a car?
Also Read: Why Does My Car AC Take A While To Get Cold?
Breaking Down How AC Affects Fuel Consumption – Step by Step
If your AC isn’t cooling like it used to, it may be time for a car aircon service to check refrigerant levels and airflow efficiency. To really understand how the AC system uses fuel, it helps to break things into parts.
Step 1: The Compressor Kicks In
Switching on the air conditioner? The first thing that jumps into action is the compressor. Its job is to move refrigerant through the system, which is what cools the air inside your car. But here’s the catch, this process isn’t free. The compressor needs engine power to function, and that extra load means the engine works harder than usual. More engine effort? More fuel burned. It’s that simple.
Step 2: Open Windows vs Air Conditioning
Plenty of drivers believe that rolling down the windows is a good way to save fuel. In some cases, they’re right. At low speeds, like when you’re stuck in traffic or driving around town, open windows don’t create much drag. The fuel savings? Not a lot, but enough to matter over time.
But on highways, the story flips. At higher speeds, open windows mess with your car’s aerodynamics. They create resistance, forcing the vehicle to work harder to stay at speed. That extra effort can actually cost you more fuel than simply using the AC.
Step 3: The Kind of Vehicle You Drive Matters
Newer cars often have smarter systems in place. Some will activate the AC compressor only when it’s needed, not all the time. Older cars, especially ones with manual controls, tend to keep it running as long as the AC is on. That constant use adds up. And if the system hasn’t been serviced? A dirty filter, low refrigerant, or sluggish compressor can make the engine push even harder, burning more petrol.
Step 4: How Long You Keep the AC Running
The longer the AC stays on, the more fuel it uses, especially when you’re in traffic or idling. Studies suggest fuel usage can go up by around 0.2 to 1 litre for every 100 kilometres, depending on how hot it is outside and how hard the AC has to work to cool things down.
Now, if you have any issues regarding the compressor or checking the above mentioned steps, and are looking for towing company Perth, we are always available.
AC Habits That May Save Fuel
Feel nervous about the amount of petrol that your AC is consuming? There are a couple of basic things you can do to make a remarkably big difference not only in the fuel efficiency, but also in the effectiveness of your AC over the years.
1. Take it Easy- do not turn it on high right away
When you enter a hot car, do not be tempted to turn on the AC to the maximum before long. Rather leave the windows open a minute or two to get the hot air out. Next, put on the fan first then reduce the temperature. This allows time to the system to cool itself down effectively but not placing undue stress on the compressor at once.
2. Apply Recirculation Mode (And When to Disengage It)
After the cabin is cooled make a switch to the recirculation mode. This location facilitates regulating the temperature because it uses the already cooled air within the car implying the compressor does not need to labour as much. It is just to keep in mind that when you leave it on too long–and particularly on a windy or damp day–the windows will be fogged up or the air will seem stuffy. Monitor that and turn to fresh air when necessary.
3. Windows Down in the City, AC on the Highway
Rolling down the windows is okay at low speeds, in city traffic. The drag is reduced to a minimum and the load carried by the engine is also lowered. However, after you get up to a speed, say, a freeway or open road, have the windows closed. Use the AC instead. It is more efficient at the higher speeds and more aerodynamic.
4. Maintain Your Car AC in a Good Condition
This is a no-compromise. The frequent servicing of your AC, namely, the inspection of the refrigerant quantity, reviewing the filters, and the condition of the compressor makes it operate more smoothly. A properly maintained system consumes less fuel, cools quicker and will last longer. And in the long-run, that is less trips to the pump.
AC Maintenance and Fixations Processes That Aid in Minimising Fuel Wastage
AC maintenance is necessary to keep the bills paid on fuel much lower, especially when you take it seriously. One or two simple checks can increase cooling efficiency, and reduce outlay in petrol.
1. Check The Whole AC system
Have a technician examine the compressor, condenser, evaporator, and connecting hoses. If any part is under strain or not functioning properly, your engine ends up compensating and that means more fuel used. Most workshops offering general auto repair will be able to help with this as part of a regular service.
2. Inspect Refrigerant levels
A low level of the refrigerant will cause the compressor to strain more in cooling the air thus placing additional burden to the engine. R-134a or R-1234yf refrigerant is being used in the majority of cars currently. Having it in a topped up state guarantees the effective performance and minimizes the use of fuel influence.
3. Clean/Replace Air Filters
The cabin filters may get clogged hindering airflow which decreases cooling capacity. This makes the AC spend additional time on producing the same outcomes. Replacing a clogged filter is an easy repair that will aid in comfort as well as fuel mileage.
4. Look Out Leaks and Strain on Compressor
Noisy and overworked compressor or leakage of the AC system implies that there lies a more serious problem. Uncontrolled, all of these may result in costly repairs-and increased fuel consumption in the meantime.
5. Never Cut Down on Certified Technicians
Never take the AC service unless it is performed by the licensed experts who know how to handle refrigerants and test the system pressure. A good tune-up makes sure your AC is not costing you in terms of your mileage.
Also Read: How Long Does It Take For A Car AC To Cool Down?
Final Thoughts: Does Air Conditioning Use Petrol? Yes, But You’re In Control
So, does air conditioning use petrol? Absolutely. Every time the compressor kicks in, your engine burns a little more fuel to keep the cabin cool.
But how much it affects your fuel bill depends on how you use it. Short city drives with the windows down, keeping the system well maintained, using recirculation mode wisely, these little choices add up.
Newer cars are already designed to be more efficient, but even with an older vehicle, you can make smart adjustments. Avoid idling with the AC on for long stretches, get regular checkups, and don’t push the system harder than it needs to go. If you are searching for car repair near me or car air conditioning service, feel free to contact us.
