They do but most reefers (refrigerated containers) have build in or portable gensets to provide power when they’re not on the ship and plugged in. They could easily spend days in the port stacks and having to plug them in every time they moved would make life a lot more difficult for the port. They can burn anywhere from a few hundred to a few thousand liters of diesel per week which isn’t actually that much to a 40ft shipping container.
How important do you think would a grid hookup be on European freight trains for reefers?
It should be straight forward to include full wagon power with the upcoming DAC4EU coupling (UIC 552 says that normal coaches are to have an 800A through connection that's regularly fed with 1000V 16.7Hz or 1500V 50Hz; this is single-wire earth(/track)-return).
Keep in mind that unlike North American freight trains, Europe mainline service is almost fully electrified. Thus the reefer would be grid-fed.
I'm asking because I'm looking to propose a change to the current plans for the electric coupler (use near-field RF instead of the currently-preferred single-pair Ethernet or it's fallback powerline; I think 802.11 has suitable PHY options, especially among the OFDM codes if the near-field chamber is dispersive and/or has problematic resonances in the channel), and throwing in "grid power for reefers" with actual numbers from the reefer container industry would be easy (a change to the coupler is a change, and the additional cable through the wagon shouldn't be that extensive either if it's an economical aluminum type; also this would allow passenger coaches that are currently using the pre-DAC4EU hook and chain coupling to be used with DAC4EU rolling stock).
I recommend talking to someone with experience shipping reefers in Europe because small seemingly irrelevant details will make or break the design. I assume that Europe uses a lot more international reefers that don't come with their own gensets so many trains would already have power in the form of generator cars. It might be impractical to hook them up to train power without a way to synchronize all the coolers so that they don't all turn on at once and brown out the train in the middle of a climb.
IIRC international reefers require three phase power with a 50 amp breaker so even 800 amps won't get you very far if they all start up at once.
It sounds like these are automated somehow, that the generator kicks in when it's not otherwise being powered - otherwise isn't it just as much work for the port to run around starting and stopping generators?
But an automated system sounds like it has its own problems, how does it make sure it has proper ventilation and comes on at the right time? Probably I don't want the container to start venting diesel fumes when it's deep in a stack of lego surrounded on all sides.
Reefers still get special treatment at ports because they have to be moved as quickly as possible. That includes not stacking them several layers deep horizontally so that ventilation is blocked (the gensets are very obvious from the outside). They’ll often get connected while in the port too, it’s just not a guarantee. Someone with more valuable produce will often pay for preferable treatment and a power connection to reduce risk from malfunction and running out of fuel.
It has to be automated since it’s a refrigeration unit that needs to know when to turn on the cooler. The control circuit starts up the generator if it senses no power connection at that time, usually off a standard marine lead acid battery.
