ARAI fuel efficiency tests should account for AC use: Govt

The Ministry of Road Transport and Highways (MoRTH) has proposed a change in how fuel efficiency is officially tested for cars in India. As per a draft notification, all passenger cars will need to undergo fuel-consumption testing with the air-conditioning system switched on as well as off to better reflect real-world use.

The draft notification issued on Thursday said, “On and after Oct 1, 2026, all vehicles of category M1 (cars), manufactured or imported in India, shall be tested for measurement of fuel consumption with air-conditioning system in operation, as per AIS-213, as amended from time to time.”

M1 category vehicles are passenger cars designed to carry up to eight occupants, including the driver. This includes hatchbacks, sedans, SUVs, MPVs and crossovers.

1. New rules are aimed at providing more realistic mileage figures
2. Carmakers to publish both mileage figures in manuals and on websites

Why this change is being proposed

Govt wants mileage numbers closer to real-world use

Currently, manufacturers publish fuel efficiency figures based on tests conducted with the air conditioning switched off, citing prevailing global test norms. However, buyers often see noticeably lower mileage in daily use, partly because the AC load is excluded from official testing.

The government believes the new requirement will improve transparency and give consumers fuel efficiency figures that better reflect everyday driving conditions.

What the proposed rule requires

AC-on test results to be disclosed publicly

If these rules are implemented, carmakers will be required to test fuel consumption (or energy consumption, for EVs) with the air-conditioning system running. Manufacturers and importers will also have to disclose results for both AC-on and AC-off conditions in the vehicle owner’s manual and on official websites.

AIS-213 standard to be used

Procedure factors in extra load from air conditioning

As per the draft notification, testing will be conducted as per AIS-213, which lays down the procedure for measuring emissions and fuel consumption with the air-conditioning system in operation for all vehicles of the M1 category.

AIS-213 is designed to account for the additional load of the AC system and the impact it has on fuel use and emissions.