// Each month, for each unique combination of generator id and prime mover// and fuel,there is one report for each generator unit in each plant.
id = Column(Integer, autoincrement=True, primary_key=True) // surrogate keyplant_id_eia = Column(Integer, ForeignKey("plants_entity_eia.plant_id_eia"),
nullable=False)
// TODO remove prime_mover since it"s specific to generator_id?
prime_mover = Column(String, ForeignKey("prime_movers_eia923.abbr"),