Thank you all for the information in this thread.
I should be able to access a 22kw three phase free charger on one of my regular journeys. From the posts above the maximum rate of charge I can get with the Model 3 is 11kw (equivalent to 40 mph) - please correct me if that is wrong.
In addition to Tesla Superchargers, what other chargers will give me over 11kw. In other words, if I am searching for suitable chargers on a map, what should I be looking for.
In practise the nominal 11kW may sometimes turn out at 12kW depending on voltage but that is indeed the car's maximum on AC charging. DC charging, or "rapid" charging, is a different ball game where the car has a much higher capability. For non-Supercharchers you are looking for chargers with a CCS connector. They generally start at 50kW upwards. A few will be up to Supercharger speeds i.e. 120kW plus ... perhaps even maxing out the capability of a Model 3 LR at 250kW.