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Net position (MW) ====== *indexed by: energy, node, test case* ### Description This KPI for each country the net trade balance for each of the energies modelled (difference between exports and imports) at each timestep. This enables to understand whether the KPI exports its production or imports energy over different timescales or seasons. This is particularly useful when analysing trade within a zone made up of different countries/regions. Additionally, this can be useful to analyse the sizing of a system with regard to a specific energy source: for instance, an electrical system with a negative net position over most of the timesteps may be undersized.

Modelling hint

It is possible to play on the aggregation and the granularity of this KPI in the "Style" tab to analyse monthly net positions for instance and understand the seasonal exports/imports dynamics.
### Calculation All the equations below are valid for any realization and are therefore implicitly indexed by test case. Let be $x_{e,n}(t)$ the net position of node $n$ for energy $e$. The net position at each timestep is calculated by summing the production of all assets producing energy $e$ at node $n$ ($A_{n, e}^p$) and removing the consumption of all assets consuming energy $e$ at node $n$ ($A_{n, e}^c$). $$ x_{e,n}(t) = \sum_{a \in A_{n, e}^p}p_{a, e, n}(t) - \sum_{a \in A_{n, e}^c}c_{a, e, n}(t) $$ *Global variables and parameters notations definitions can be consulted [here](../notations.md).* ### Indexing - The energy index refers to the energy produced/consumed - The node index refers to the node in which energy is produced/consumed - The test case index corresponds the test case of the realization variables and parameters are taken from