NEW DELHI: Amid delays in rolling out the indigenous Bharat Vecto testing tool for truck fuel economy, the Bureau of Energy Efficiency (BEE) is considering introducing constant speed fuel consumption (CSFC) norms from April 2027 as an interim measure, with a possible shift to the more comprehensive Vecto-based testing in a later phase.
While the first phase, or block period, will run for three years until March 2030, the BEE is open to incorporating Bharat Vecto-based targets in the second phase from April 2030 to 2032, according to two people aware of the development and a government document reviewed by Mint.
The block period arrangement takes a leaf out of BEE’s own July 2026 proposal for CAFE 3 norms for cars, and will be used for assessment of whether automakers have met their fuel efficiency targets.
"The two block periods system that was proposed for corporate average fuel efficiency 3 (CAFE 3) norms could be a part of truck fuel economy norms also, and this could be used in a way where Bharat Vecto can be completed and then used in the second block period," said the first of the two persons cited earlier, both speaking on condition of anonymity. This person added that discussions between industry representatives and government will create a firm plan for the rollout of this fuel efficiency regulation.
Constant speed fuel consumption norms measure a truck's fuel use at fixed speeds under controlled conditions. By contrast, Bharat Vecto is a more comprehensive tool that evaluates fuel consumption and carbon dioxide emissions in real-world driving conditions. These fuel economy norms seek to improve overall efficiency in the truck segment while encouraging the adoption of cleaner alternatives such as electric trucks.
The BEE's proposal assumes importance as these diesel-fuelled vehicles, which account for less than 5% of all vehicles in the country, contribute a third of the transport sector's carbon dioxide emissions.
Bharat Vecto, or the Bharat Vehicle Energy Consumption Calculation Tool, is designed to simulate real-world driving conditions on Indian roads and assess the fuel efficiency of trucks. The tool is based on Europe's Vehicle Energy Consumption Calculation Tool, or Vecto. It is being developed by the Automotive Research Association of India (Arai).
Arai began developing Bharat Vecto in January 2025 at the direction of the Union road transport and highways ministry. The testing agency has said on its website that it plans to launch the tool for diesel vehicles by December 2026. However, the tool is likely to take longer to develop and for the industry to standardize its use, according to the people cited above.
The auto industry is pushing for Bharat Vecto to replace the constant speed fuel consumption (CSFC) test currently used to regulate truck fuel economy. Under the CSFC test, vehicles are driven at speeds of 40 kmph and 60 kmph on test tracks to measure their fuel efficiency.
The Bureau of Energy Efficiency under the Union power ministry is India’s apex energy efficiency regulator, overseeing products and sectors ranging from vehicles to household appliances. The Automotive Research Association of India is among the country’s leading vehicle testing and research organisations and has played a key role in advancing green mobility by certifying cleaner vehicles and fuels for critical government policies.
Some experts said that in case new Bharat Vecto targets are set three years after enforcement of new CSFC norms, it is imperative to understand the relationship between the results of the two tests.
“In order to streamline development efforts at the OEMs (original equipment manufacturers) end, it is necessary to understand how varied the targets are going to be once Bharat Vecto is brought in,” said Ashim Sharma, Senior Partner and Business Unit Head at Nomura Research Institute (NRI) Consulting and Solutions, India. “For example, aerodynamics of the vehicle, which can generate drag and impact fuel economy, can account for a different share of the overall test based on the share of different driving speeds in the test cycle, similarly, other parameters can also change resulting in differences in modelling of vehicle characteristics in the two tests. And this difference is crucial because it would determine where automakers need to spend resources, as there is always a trade-off between cost and where you put your resources.”