The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- UnitPerVolumeUnit (3 members)
- Bus (0 members)
- Disposition (5 members)
- Aircraft (2 members)
- NonEnergyUse (0 members)
- Thermal (0 members)
- FluidOunce (0 members)
- CoalPowerUnit (2 members)
- Kilo (0 members)
- SolidBiofuel (2 members)
- GreenhouseGasEmission (1 member)
- PowerToAmmoniaSystem (0 members)
- Lumen (0 members)
- GesamteExtensometerDehnungBeimBruch (0 members)
- ZeroDimensionalContinuantFiatBoundary (0 members)
- NichtNachgewiesen (0 members)
- MarginalCost (0 members)
- FractionValue (3 members)
- PumpedHydroStoragePowerPlant (2 members)
- NameplateCapacity (0 members)
- MineralOilRefiningProcess (0 members)
- ProtectedArea (0 members)
- Continuant (4 members)
- RenewableElectricalEnergy (1 member)
- MarineCurrentEnergyConvertingUnit (0 members)
- PhysicalDimension (0 members)
- KilowattHour (0 members)
- WaterwayNetwork (0 members)
- Material (3 members)
- TaxonomicBridgeOntologyModule (0 members)
- IndustrySector (0 members)
- GasworksGas (0 members)
- Cost (7 members)
- ChemicalSubstance (0 members)
- NuclearBindingEnergy (0 members)
- LatentSolidFluidHeatStorageObject (0 members)
- MyOwlTestClass (0 members)
- SectoralEmission (0 members)
- Rood (0 members)
- WaterTurbine (0 members)
- SubBituminousCoal (0 members)
- MaterialStructure (3 members)
- NonMetallicMineral (0 members)
- EnvironmentalTemperature (0 members)
- SolidRenewableFuel (0 members)
- GasolineCar (0 members)
- ElectricTractionMotor (0 members)
- FreightTrainStation (0 members)
- SoftwareLicence (0 members)
- TemplateGeneratedOntologyModule (0 members)