By 2016, Sweden had deployed several electric buses across its cities from different manufacturers – including its very own Volvo. These buses had to be charged overnight at depots and then operated throughout the day.
However, this wasn’t ideal, as buses had to return to depots to recharge, and each manufacturer required their own custom charging stations.
Flash or opportunity charging technology had started to makes waves by then, which allowed buses to quickly top up their batteries on the go, enabling continuous operation throughout the day.
To add this feature in their buses, manufacturers began developing their own custom charging solutions to meet this need.
While this approach worked well for bus manufacturers, it posed a major problem for city administration that wanted a common, shared charging solution. Different configurations meant the systems were not interoperable. A city cannot realistically install different flash charging systems depending on which bus type operates on a particular route.
So, manufacturers like Volvo, Solaris, VDL, Irizar, and others came together to develop a universal flash charging standard – one that could work across all their buses, and be easily adopted by other manufacturers as well at later point of time.
This collaboration led to the birth of “OppCharge” – an open, standardized interface for flash charging buses.
This specification outlined how bus manufacturers could adopt a common charging interface, allowing their vehicles to use shared flash charging units installed across the city for quick top-ups during operation. It required installing two standard sized metal bars on top of e-buses.
The spec also defined:
1. Mechanical geometry
2. Electrical configuration
3. Communication protocols
4. Safety sequence etc… that was needed to make it work.
From 2016 onward in Sweden, buses from these manufacturers were built with OppCharge roof rails making them “flash-charge-ready”.
India’s case
This pantograph based charging technology is still not in place, and although a few bus manufacturers are reportedly developing it, the absence of a common standard risks creating the same fragmented ecosystem that Sweden experienced in 2016.
Transportation minister Mr. Nitin Gadkari had recently announced that the country’s first flash-charging electric AC public bus with a seating capacity of 135 passengers will soon be launched in Nagpur as a pilot project.
North America defined its standard “SAE J3105” which was heavily influenced by OppCharge interface. Although it also included trucks in its specifications.
The Indian government will need to step in to ensure all bus manufacturers adopt a standardized solution that can work with the flash chargers installed across our cities.
It’s crucial for our govt to act now — many electric buses in our cities still break down when they run out of charge, and towing them away in the middle of traffic often causes massive jams.
Flash charging is bound to become a reality sooner or later. It can extend range, reduce battery size, boost efficiency, and lower costs for transport authorities.
It’s in the country’s best interest to fast-track this technology and establish a common standard that works across all bus types and cities.
