Accurate Allocation of energy in production processes - the importance of using metamodels

2. Allocating shares to sinks and conversion nodes.
As the goal is to get to the distribution over the final customers (the sink
nodes), the next step is to further distribute the share of consumption
allocated to the distribution and conversion nodes. This describes the
actual physical flow of the commodity types from the distribution node
into the other nodes (sink and conversion nodes) . It is used to spread
the total amount of commodity used over all the physical users of the
commodity type.
3. Allocating indirect consumption from conversion nodes to sinks
The final step redistributes the flows that have gone into conversion
nodes. All users of the converted commodity, in other words, will get
their share of the primary commodity they indirectly consume. This
partition is crucial for transferring all costs - both direct and indirect -
for all commodity types to the internal end customers of the company.
The description above illustrates the power of graph models. The logic of
partitioning is already built in, so to speak. It defines the energy type sources,
conversions and sinks for all the energy types provided by the company. Meters
can be mapped to the flows of the graph model for all the periods relevant for
the company - whether it is weeks or months - and their totals calculated over
those periods.
Application: conversion efficiencies
The first application is straightforward. For each conversion node, the efficiency
of the conversion is easily calculated using the input and output flows. Every
input-output combination gives rise to a particular efficiency.
For example, a combined heat power converter has a single natural gas flow
input and two output flows, heat and electrical power.
Application: cost allocation
All costs for the acquired commodity types like, gas, water & electricity need to
be allocated to the internal customers who use them. In addition the costs for
converting acquired commodity types to derived commodity types (e.g. hot
water, resulting from the combination of water and gas) need to be allocated
to the internal customers that use these derived commodity types.
Direct costs are fairly easy to allocate, as they can be linked to the meters which
record the commodity type usage. The challenge is to correctly assign indirect
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