Index I indicates the i:th customer of n related to a node.
Summing of energy period 1:

Summing of energy period 2:

Summing of nominal power:

Summing of area/volume:

Summing of nominal flow:

Summing of water consumption period 1:

Summing of water consumption period 2:

Summing of cooling:

Summing of return temperature:

Summing of equivalent bypass:
