Kaushal Atodaria
Pranav Srivilasan
Stations down, broken connectors, connection failures, low power output, damaged screens, payments stuck. Not an uncommon experience for users at public EV charging stations around India, or even in many EV markets worldwide.
Charging anxiety is probably the biggest hurdle to EV adoption—maybe alongside the upfront cost of an EV in a buyer’s mind. “Charging anxiety” is something we define as what happens when long charge times meet sparse, unreliable charging networks. We solve the first half of the problem with our 15-minute charging technology, but the second half is equally important.
Rapid charging without a good network solves nothing.
The very best networks globally, like Tesla’s Supercharger network in the US and Fastned in Europe, have claimed charger uptimes of 97-99%. The worst networks in, for example, North America have been found to have reliability as low as 60-70%—i.e. they are out of order for more than 100 days a year on average.
In India, public charging has gradually improved, with decent networks managing uptimes of around 85%, though a lot of the weaker operators remain at ~70% levels.
Uptime on our network?
95-96%
Intent
There are some common issues every network operator faces in India:
Users don’t always treat the charger well, dropping charging guns on the road, damaging connectors, and increasing wear and tear.
Vandalism and poor civic maintenance means that the entire space of a charging station deteriorates.
Electrical grids vary greatly in quality from state to state, with frequent power cuts or local transformer/line failures.
Both voltage drops and spikes are widespread; in some places, we even see phase de-sequencing of three-phase power.
In the face of all this, the most important driver of network reliability is just the operator’s intent to deliver a great experience.
Many networks see around 3-4 charging sessions per day per charger, or even less. Not enough revenue is generated to cover the capital expenses of a high-power DC charger plus rent for the location.
For us, the charging network is a core part of our business. And 15-minute charging makes it possible to run a profitable, sustainable network. The top 30% of our e^pumps in every city charge 25-30 vehicles every day on average—our record is 69 vehicles in one day at a single charger, which might be the highest in the world. If a charger is down for even a few hours, that’s a significant loss for us.
For us, the charging network is a core part of our business. And 15-minute charging makes it easier to run a profitable, sustainable network. Our e^pumps in Bengaluru charge 25 vehicles a day on average—our record is 69 vehicles in one day at a single charger, which might be the highest in the world. If a charger is down for even a few hours, that’s a significant loss for us.
Result: uptime is a top priority for us as a business.
We continuously monitor every location on our network. Every issue is detected as soon as possible whether it’s a damaged connector, a faulty pump, or a random vehicle blocking our station. In every city where we operate, we have maintenance teams on standby 24x7. Whenever there’s an issue, we run to deploy a fix.
All this might sound very straightforward, but the frequency of issues in Indian conditions—from grid to hardware—requires frequent maintenance.
Our ability to do that is downstream of our intent to deliver high reliability.
Product
Having a good charging station is the second piece of the puzzle, in terms of both hardware and software. This is an area where a lot of the older EV chargers in India fell short, especially those set up in government tenders before 2019 or 2020. Though the hardware today has improved significantly, there’s still a lot more to be done in terms of reliability and consistent performance.
E.g. users still run into problems like charging sessions not starting properly or the gun/connector getting damaged or the power output being below what they expect. Public charging involves coordination between vehicle and charger+network, both sides engineered and owned by entirely separate entities. Even with a common protocol like CCS2, charge point operators need to keep updating their software and firmware as charging methodologies evolve and newer hardware with better reliability gets designed.
At Exponent, we have the advantage that we’re a two-sided energy player—we handle both the charging station and the battery management system in the vehicle. Seamless coordination between the two helps us deliver hassle-free charging sessions.
At Exponent, we have the advantage that we’re a two-sided energy player—we handle both the charging station and the battery management system in the vehicle. Seamless coordination between the two.
We’ve also designed and built our e^pumps from the ground up. It’s tailored to our network needs and also something we’ve constantly tweaked and updated as we discover more failure modes in the field. Every issue or failure is something we take and quickly go back to correct through some mix of hardware design and firmware updates.
We bake in a lot of detection and telemetry capabilities into the charger. This lets us constantly monitor every station and catch problems as and when they pop up, and we get genuinely actionable insights.
Constant improvement is the name of the game.
As good as our charging product might be today, we’re still working on making it better, on everything from the sturdiness of the connector to the ease of use for a driver to the reliability of the power electronics.
Planning
And finally, we have planning—across network design, routing and communication with vehicles and drivers.
High intent and a robust product cannot guarantee 100% uptime, as much as we would like it to. A fault or outage is sometimes unavoidable in any system at scale. And this is where we step back and look at charging not only as maximizing the uptime or reliability of every single charger, but also about delivering a good charging experience to the driver anywhere.
The way we lay out our network in every city we enter is that we look at the routes that customers travel, traffic patterns and utilization trends. On top of that, we see the network as a system meant to deliver energy to each driver at any time and any place.
We plan in clusters of chargers. Every charging point we place broadens our network coverage but also acts as a backup to chargers around it—no charger is more than 3-4 km away from another one. If there’s a grid outage at one charger on a driver’s route, we can immediately reroute them to another one nearby. And we spread out the network in such a way that on frequent routes there are multiple options to charge without taking a big diversion.
E.g. a driver going from an e-commerce company’s hub to a common delivery area will find a charger near the hub, near the destination and one or two near different points of the route.
Redundancy + real-time routing ensures you always hit a working charger.
At the end of the day, 15-minute charging is all about giving freedom to the EV owner. And that needs to come with the confidence that you can actually charge right when you need it.