Depending on the chosen aggregation method in the model settings, we will aggregate the diversified DHW and diversified CH flow/power in a pre-defined manner.
Aggregation method: Maximum of CH and DHW
Within one dwelling we will aggregate the DHW and CH flows/powers using the “maximum method“ as explained in https://hysopt.atlassian.net/wiki/spaces/HRM/pages/3089367263/Step+6+aggregation+of+the+DHW+flow+power+with+the+CH+flow+power#Maximum-of-central-heating-and-diversified-DHW-flow .
Why? Either the HIU is in DHW tapping mode, either the HIU is in CH mode.
Aggregation method: Weighted average of CH and DHW (Hysopt optimisation of sum-aggregation)
Within the weighted-average method, Hysopt will also calculate the “maximum of CH and DHW” aggregation for a single dwelling, as explained in more detail in https://hysopt.atlassian.net/wiki/spaces/HRM/pages/3089367263/Step+6+aggregation+of+the+DHW+flow+power+with+the+CH+flow+power#Maximum-of-central-heating-and-diversified-DHW-flow. The main reason for applying the maximal method within the weighted average framework for a single dwelling is that a HIU is either in DHW tapping mode either in CH mode.
As soon as multiple dwellings are involved, the weigted average aggregation method differs from the maximum of CH and DHW method.
Aggregation method: Sum of CH and DHW (based on Cibse2020)
Within the aggregation method “Sum of CH and DHW”, we will simply add the diversified CH and diversified DHW power/flows. That same procedure is also applied to single dwellings.