A Giant Charger That Juices Up Electric Buses in Three Minutes

To keep its customers on the road as much as possible, Tesla has built an international network of Supercharger stations, which can charge the battery in the Model S halfway in just 20 minutes. It’s a good alternative to slow setups that can take hours to charge vehicles, and allows for long-distance journeys if the […]
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Furrer+Frey and Opbrid

To keep its customers on the road as much as possible, Tesla has built an international network of Supercharger stations, which can charge the battery in the Model S halfway in just 20 minutes. It’s a good alternative to slow setups that can take hours to charge vehicles, and allows for long-distance journeys if the driver's happy to stop at a rest area for a stretch every few hours.

But that model doesn’t work for electric vehicles that can’t afford to stop for 20 minutes at a time. Take, for example, city buses. They need something else. Something faster.

That's why Opbrid, a Spanish firm specializing in automatic charging systems for urban commercial vehicles, has designed the Busbaar V3, a new design for charging electric or hybrid buses for just a few minutes at a time, at a rate way beyond what Tesla’s Superchargers produce. And now, they're being sent to Sweden for a test run.

Vehicles like city buses and delivery trucks are tempting candidates for electric powertrains. Internal combustion engines are at their least efficient when they’re used in urban stop-and-go traffic, and it’s easy to manage charging for vehicles that follow regular routes.

The Busbaar, introduced last month at the IAA conference, an annual trade show for commercial vehicles, looks something like the pantograph that pops up from high-speed electric trains to connect to overhead power lines. The Busbaar, though, comes down from a fixed position, hooking into a bus that parks beneath it, via a large copper bar installed on top of the vehicle.

The idea is to install it at stations where buses stop for a few minutes at a time, in high-traffic areas or at the end of the route. The bus will get in a quick charge, enough to top off the battery. When charging is complete, the pantograph pops back up into the Busbaar's stand and the bus gets going again.

The technology is similar to that used by electric streetcars and high-speed trains, using conductive charging and off the shelf parts. Unlike one inductive bus charging system being tested in South Korea, which uses magnetic charge plates built into the ground, the Busbaar can be installed with relatively little hassle.

The Busbaar (and its sibling, the Trukbaar, aimed at garbage trucks and the like) charge at a whopping 650kW, a huge increase from the 120kW that Tesla chargers provide (which are themselves more powerful that most EV charging setups). When combined with fast-charging lithium-titanate batteries, electric buses only need to charge for three to four minutes at a time before continuing on the rest of their route. Lithium-titanate batteries charge much faster than their lithium-ion counterparts, and fast charging doesn't degrade them. They do have a much lower energy-density, but that's not a problem on a bus that has room for a larger battery. And since it's being charged frequently, the battery doesn't need to store so much energy to begin with.

Opbrid says the first three Busbaar charging stations will be installed in Umea, Sweden this fall for use with the city's existing 18-meter electric "bendy" buses. Costs for the system have not been released.