Projects in progress

PROJECT:

“HOSTING CAPACITY ANALYSIS FOR STREAMLINING PROSUMERS’ GRID CONNECTION APPROVALS”

Supporting institution: Open Socety Foundation Western Balkans

Implementation time: October 2024 - November 2025.

The aim of the project “Hosting Capacity Analysis for Streamlining Prosumers’ Grid Connection Approvals (OSF-WB HCA)” was to address technical barriers within the distribution grids for the accelerated integration of small-scale rooftop solar photovoltaic (PV) prosumers. The project focused on building capacity within selected Distribution Network Operators (DNOs) - CEDIS in Montenegro and EP BIH in Bosnia and Herzegovina - by providing training and technical assistance for enhancing their grid connection procedures through the application of the Hosting Capacity (HC) methodology.

PROJECT OBJECTIVES AND PROGRESS ACHIEVED

The project pursues two strategic objectives:

1. To initiate and guide discussions on grid connection procedures that enable scalable integration of distributed photovoltaic (DPV) system - particularly rooftop PV - into medium-voltage (MV) and low-voltage (LV) distribution grids.
2. To launch the digitalization of planning and operational activities within DNOs.

Progress in Achieving Objective A: Grid Connection Procedures for DPV Integration

MV Grid Connection Practices

Grid connection approval procedures at CEDIS and EP BIH were evaluated. Both DNOs use commercial simulation tools - PSS®Sincal in CEDIS and DIgSILENT PowerFactory in EPBiH - to assess DPV integration into MV grids. These assessments follow national grid codes and technical regulations. CEDIS has already approved approximately 200 MW of DPV capacity in MV grids and EP BIH 234 MW.

However, both DNOs rely on static snapshot simulations using estimated load and generation values. These simulations typically model worst-case scenarios - maximum DPV generation during minimum local consumption - without dynamic or time-series analysis. This approach results in conservative assessment of MV grid hosting capacity. Therefore, neither DNO uses systematic HCA based methodology to determine the maximum capacity of a DPV unit that can be connected to a certain MV node. Hence, information regarding available HC for each MV node is not published meaning that the process of issuing grid connection approvals is not transparent.

LV Grid Connection Practices 

Neither DNO performes grid connection studies for LV PV prosumers, although in EP BIH an in-house open-source software (NNA) is used for approval of new load connections in LV grids. Using simulation software for LV grids requires automatic formulation of a electric grid model using available data. Both DNOs use GIS system (in EP BIH open-source QGIS and in CEDIS commercial MapInfo) and related Meter Data Management (MDM) systems, where required data are available. However, the reliability of data in the GIS data base in CEDIS is inadequate. More importantly, interoperability between data bases in both DSOs is not ensured.

Project outputs 

During the HCA project capacity building of technical staff of DNOs has been performed providing training and illustrating feasibility of automatic hosting capacity calculation is selected pilot projects using an open-source software (PandaPower).

Progress in Achiving Objective B: To launch the digitalization of planning and operational activities within Distribution Network Operators (DNOs).

Since the biggest challenge in both DNOs during DPV grid impact analyses is the lack of reliable and validated grid (network and load) data and complexity of data entry process into simulation software, digitalization of DNOs, or transition to a DSO model, was identified as the biggest “soft barrier” to deployment of DPV. In this project several software solutions were tested to enable smooth interoperability between the used data bases, with the aim to enable automatic formulation of the electric grid model in the selected PandaPower software.

Project outputs

The first phase of digitalization of DNOs, implemented for the grid connection approvals and planning activities, has been initiated. In the later stages of digitalization the DNOs will be able to use HCA in planning DPV deployment and in developing reconstruction and modernization plans. Also, the HCA methodology can be apllied in determining HC for other Distributed Energy Resources (DERs), like Electric Vehicles (EV), heat pumps (HP) and Battery Electric Energy Storage (BESS) systems. Dynamic HCA methods enable modeling of control operations of DERs (i.e. like voltage control of PV smart inverters) while determining hosting capacity thus providing an analytical tool for analyzing smart grid concepts. These steps will enable more advanced phases of the digitalization of DNOs.

PROJECT IMPLEMENTATION TEAM 

For each country a national coordinator with the requisite expertise and credibility with the DSOs was appointed:

• Professor Samir Avdaković (Faculty of Electrical Engineering, University of Sarajevo) for Bosnia and Herzegovina,
• Professor Zoran Miljanić (Faculty of Electrical Engineering, University of Podgorica) for Montenegro.

Additionally, renowed experts in the field of distribution grids and ICT were selected:

• Professor Nermin Suljanović (Faculty of Electrical Engineering, University of Tuzla and Senior Expert at the Electrical Institute Milan Vidmar, Ljubljana) for strategic guidance on data management, algorithm selection, and open-source software development,
• Professor Jasna Hivziefendić (International Burch University of Sarajevo) for development of the methodology/guide for HCA in medium-voltage (MV) and low-voltage (LV) grids,
• Damir Kapidžić (PhD candidate, International Burch University of Sarajevo) for all aspects of data management - including retrieval, validation, verification, and interoperability - as well as the development of an automated model-building concept using the pandpower open-source software and its application in pilot project in EP BIH,
• Ajla Mehinović (PhD in Electrical Engineering) for the development of open-source software tailored to HCA in low-voltage (LV) grids, with application in pilot projects in CEDIS,
• Project administration was handled by Naida Panjeta (MSc in Electrical Engineering, University of Sarajevo), who joined RESET as a full-time employee in September 2024.
• The project was managed by Professor Emeritus Mirza Kušljugić (Faculty of Electrical Engineering, University of Tuzla and at the time President of RESET Centre).

Close cooperation with technical teams from DNOs was established enabling follow up activities. Important aspect is encouragment of information exchange between CEDIS and EP BIH initiated organizing reciprocal visits and one day workshops in Sarajevo and Podgorica.

https://osfwb.org/publication/technical-aspects-advocating-for-policy-and-technical-solutions-for-sustainable-distributed-green-energy-in-the-western-balkans/

Attachment:

Hosting Capacity Analysis and Maps GUIDE