I can drop the power provider, drop a substation or power pole, next to it, but I get the following error when trying to connect the substation or power pole to the power grid (only when in conjunction with a power provider):

Error while running event ElectricTrain::on_tick (ID 0)
LuaEntity API call when LuaEntity was invalid.
stack traceback:
ElectricTrain/lua/logic_event_handler.lua:99: in function <ElectricTrain/lua/logic_event_handler.lua:62>

Any clues?

have you installed the last version?

Yeah v 0.16.8 added and maintained inside Factorio using the mods interface.

0.16.11 same

that is not possible ... which mod do you use

Have the same problem now, crash when connect provider to electric grid. Mod 0.16.12, game 0.16.51.
Capture error http://piccy.info/view3/12878578/990052a111d57082824224b57934a600/
What may cause this error ?

do you use other mods. it is possible to get your savegame