Not arguing any of that. My boy has a plug in that is relegated to around home, and a hybrid that goes anywhere.
It does well on milage as I understand it. Not just in town, but out on the open road it does somewhat better than an all gas version of the same {I think}.
As you say - the camming and whatnot for gen-set use may be a big part of that difference.
Hybrids don't have much battery at all, compared to a plug-in.
More like a capacitor I think.
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My buddy just got a new GMC Denali EV. What a truck! Crazy fast. Super range empty (700kms). Crappy when pulling a big trailer though.
He pulled his big pontoon from Stratford to North Bay and had to charge 2x on the way up and ended up having his BIL with a gas Yukon tow it home.
If it is a diesel generator and since generator don't drive wheels, dyed diesel could be used. That would be a huge plus for farmers, ranchers contractors etc that have fuel 👌.
weak point is battery's and control module. Diesel generator is heavy especially since they are talking about. Not sure how much pay load truck would have left. Between batteries and generator might not be much.