New energy busses now always are connected to the ENERGY_VECTOR of the first asset that is connected to it (comp. here). In case of energyConversion assets, this is actually not quite accurate: If an electricity bus is first defined by a heat pump connected to it, which has energyVector "Heat", the bus is defined incorrectly.

The energy vector of a bus is used to define the excess sink connected to it. As such, currently, the energy excess sinks may right now be of an incorrect energy vector and be counted into the KPI connected to excess energy incorrectly (also considering weighting). As such, one should right now look at the scalar_matrix and not the scalars to determine the excess of sector-coupled systems.

Originally posted by @smartie2076 in #555 (comment)