[labawi]

> It probably wouldn't need much of a resistor to simulate minimal charging rates.

Resistor wouldn't be a huge problem. A heat sink might be - the chargers typically support 5-50kW¹ charging rates. I'm not sure they would consider 100W or so "charging", so you might end up with something bulky.

¹ a guesstimate

[nikau]

Easy, just need to find a resistor bank like they use on metro trains for braking and bolt it on the roof.