If you want to use a Transformation to install capacity from a secondary Function, you can define Resource Requirements similar to those for a Service – see 10.3.27 Resource requirements – the only difference being that these requirements are always made on the Basis of the Transformation Output – a Transformation specifies a Basis for each of its Inputs, but only has one Output.
You must ensure that the Capacity Unit of such a secondary Resource is compatible with the units of demand for the Transformation, so that if, for example, the Basis of the Transformation is Resource Installed Units, the capacity of the secondary Resource is defined in terms of units of the primary Resource.
Costs arising from the used capacity of any Resources used by a Transformation are allocated to that Transformation in proportion to the capacity it uses. These costs are passed back in turn to the various Inputs of the Transformation. Costs arising from the slack capacity of equipment are allocated directly to Services according to their historical usage of the Resources, including the indirect usage through Transformations – see 10.3.4.1 Allocating costs through Transformations.