Using hybrid distributed energy resources as non-wire alternatives to minimise investment costs

The trend of increasing electricity demand and policies promoting clean energy generation are leading to an increase in the use of distributed energy resources (DERs). These distributed resources can be used as non-wire alternatives (NWA) to eliminate overload and voltage problems in the grid, instead of relying on network reinforcements. To accomplish this, it is essential to determine the optimal location and type of energy resource.This paper presents a mixed-integer nonlinear optimization problem for determining the optimal location, selection, and sizing of distributed energy resources. The formulation includes the possibility of associating generation resources with energy storage systems to form hybrid plants that can solve network problems. The proposed method is tested on the CIGRE European Medium Voltage Distribution System using two load scenarios that lead to different grid problems. The results indicate that the use of hybrid systems reduces the total investment cost of the solution compared to the use of generators alone. Additionally, results allow inferring the importance of properly sizing the energy storage in terms of power and energy to match the type and duration of the problems.