(OT, about hypothetical BEV rx trailers, moved to a self-replay to make it a little less bad): is this already a thing for caravan trailers? An oversized generator for off-grid camping paired with some battery for load smoothing and a downlink to the car so that it does not require the enormous capacity that would be needed to solve that once-per-year worst case outlier as a BEV. Might even be modular, like a pickup truck, a "power trailer" for adding both range and cargo bed to a car tailored for transporting humans.