Here in Nordic countries there are several options for electric pre-heater. One of the most used nowadays is TT-thermo heater with built in circulation pump. This can be connected for example on the coolant hose from engine to water valves. Traditional manufacturers like Defa and Calix also have there own models.
Fortunately 3.0d has Webasto from the factory and can easily be coded as pre-heating version. Battery charger and battery heater also in use so no problems even in -30 C.
