1 HN user recommended this documentary1 month2019–2024score 1
Years with an HN recommendation, 2007–2026
HN commenters cite it as a concrete, working example of large-battery electric shipping with fast automated charging.
Fully Charged rides a 100% battery-electric ferry across the 4 km strait between Helsingborg, Sweden and Helsingør, Denmark. The ferry crosses up to 46 times a day and charges for a few minutes at each side. The video shows the charging setup, including the robot arm that couples the charger.
“I recently saw this Fully Charged video about a short, but very frequent, ferry crossing that is now fully electric” (HN, 2019)
I recently saw this Fully Charged video about a short, but very frequent, ferry crossing that is now fully electric, with automated charging at both ends of the trip The scale here is enormous, and just for a 4km journey [this video]
Fully electric short ferry crossing with automated charging.
Different battery chemistries have different C-rates, which is the rate at which a battery can be charged and discharged: [link] [link] And generally bigger battery packs can charge at higher kilowatts. Here's an electric ferry with a 4.1 MWh battery which can charge at up 6 megawatts. 600 amps at 10,000 volts: [this video] So, like the ferry, these aircraft probably have big batteries that they charge enough to get to the next destination with a buffer for emergencies. The closer you get to 100% state of charge the slower the system will charge in order to protect the battery.
Example of ferry with large battery and fast charging.
The ferry between Helsingør in Denmark and Helsingborg in Sweden has a 10MW charger at each side, to charge for 4-9 minutes depending on the timetable. (It runs back and forth all day and all night, carrying people, cars and trucks.) See the chapter "Robot Arm" in this video to see it coupling. 10MW is around the power for an electric freight train, so these kind of numbers aren't uncommon for a port. [this video] [link]
Shows the robot arm coupling charger to the ferry.
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