The impact of the Supreme Court order banning registration of diesel cars with 2,000-cc engines in Delhi till 31 March, 2016, will be gauged only by sales numbers in the next three months.

Mahindra & Mahindra (M&M) was the first company to say there would be an impact of about 2% on its monthly car sales, while the rest are yet to quantify.

The SC order was passed by a bench headed by Chief Justice of India T S Thakur last week.

Within days of the ban comes another significant development: Retrofitted electric buses.

On 21 December, a diesel bus was converted to a battery-operated electric bus and was unveiled at an event in Parliament.

The prototype has been developed by KPIT Technologies, a Pune-based company that provides engineering and IT solutions to the transportation sector, among other verticals. The company developed the prototype in consultations with the Central Institute of Road Transport.

Prime Minister Narendra Modi, who attended the event, said Indian Space Research Organisation (Isro) would be making the Lithium-Ion batteries for such retrofitted electric buses at a cost of Rs 5 lakh, as against the current imported cost of Rs 50 lakh.

The NDA government plans to embark on large-scale conversion of diesel buses to electric buses based on the success of the pilot project.

It now remains to be seen whether the move will eventually lead to state transport undertakings and travel agents switching over to electric buses, once the project turns out to be successful and capable of being implemented on a large scale, along with a key infrastructure — recharging of batteries — being put in place.

The switch, even if gradual, could alter the bus segment in the commercial vehicles sector in India.

The domestic industry size of buses was approximately 81,653 vehicles last year, consisting of 36,837 medium and heavy commercial vehicles (M&HCV), and 44,816 light commercial vehicles (LCVs), according to Ashok Leyland's 2014-15 annual report. The company sold 13,151 M&HCV buses during the year. 

However, in the initial stages, LCVs are likely to be retrofitted, while the process may be difficult for MHCVs.

While bus-makers could face uncertainty due to the disruptive technology, state transport undertakings are bound to see a reduction in their operating costs. The other upside is cities that account for a substantial part of diesel buses are likely to witness less pollution.