Comparison of different model formulations for modelling future power systems with high shares of renewables – The Dispa-SET Balkans model

Power system’s operational flexibility represents its ability to respond to predicted or unexpected changes in generation and demand. Traditional policy and planning models in most cases do not take into account the technical operating constraints that are directly responsible for its operational flexibility. Nevertheless, this capability becomes increasingly important with the integration of significant amounts of renewables whose variability involve additional stress for the power system. Incorporating flexibility can significantly change optimal generation strategies, lower total system costs and improve policy impact estimates. The goal of this research is to prove that, for computational efficiency reasons, it is useful to cluster some of the original units into larger ones. This process reduces the number of continuous and binary variables and can, in some conditions, be performed without significant loss of simulation accuracy. For these purposes, the Dispa-SET unit commitment and power dispatch model that focuses on the balancing and flexibility problems in the European grids has been applied to the Western Balkans power system. Various clustering options are implemented and tested from the same dataset: the binary formulation considers aggregates very small or very flexible units into larger ones with averaged characteristics; the integer clustering formulation considers one typical power plants per technology; and the LP formulation additionally simplifies the mathematical formulation by neglecting minimum up and down times, start-up costs and minimum stable loads. The results show that the difference between disaggregated and clustered approaches remains acceptable and for certain accuracy metrics falls within a 2 % margin. This is especially true in case of highly interconnected regional systems with relatively high shares of hydro energy.

PAVIČEVIĆ Matija;  KAVVADIAS Konstantinos;  PUKŠEC Tomislav;  QUOILIN Sylvain; 

2019-06-24

ELSEVIER SCI LTD

JRC116964

0306-2619 (online),   

https://publications.jrc.ec.europa.eu/repository/handle/JRC116964,   

10.1016/j.apenergy.2019.113425 (online),