Steve;
They aren’t trying to cook anything in that insulated box car. They are just trying to prevent anything in it from freezing. -30C is common on the ONR route to Moosonee, so they have to think of keeping a lot of the goods they transport, from freezing.
That box car, and I think they have a few of them, is used for a lot of small shipments, like food and drink. It is treated like the old LTCL shipping that the railroads used to do, all over the continent.
There are no roads up to James Bay, so it’s either ship by boat, through Hudson Bay, by air at great expense, or by rail, which is much less expensive. Almost all passenger trains on the ONR have one of these cars on them, from Cochrane, up to Moosonee. A lot of the residents up there and along the line, order their groceries from as far South as North Bay, or Ottawa, and have them shipped up in these cars.