Från mikro till Mega-GRID: Interaktion mellan mikronät och aktiva distributionsnät

Projektbeskrivning

Projektet syftar till att påskynda introduktionen av mikronät genom tre olika lösningar, vilka kommer att valideras i en rad testmiljöer. Utöver detta kommer tre demonstrationsanläggningar utvecklas i Sverige och Frankrike. Målet med detta är att skapa ny marknadsmöjligheter för olika intressenter och att därmed accelerera utvecklingen och integrationen av mikronät.

What are the main lessons from the project?

The simulations of the project showed that the integration of microgrids (MGs) to the distribution system can offer economic benefits to the system’s operation even if the MGs locally optimize their energy transmission and peak power costs. If the distribution system operators (DSOs) had the possibility to control the MGs themselves, further savings could be achieved for the system operation (e.g., through peak power reduction which translates to reduction of the subscription fee that guarantees a certain power level). The simulations also showed the effect of the different types of battery models on the battery utilization and by extent on the daily energy cost reduction of the MGs. E.g., battery models that considered degradation resulted in less cycling of the batteries.

The demonstration activities of the project revealed several challenges regarding the online control of the MG resources through the energy management systems of MGs with the aim to optimize the operation of the MG (e.g., energy cost minimization). These refer to:
- The integration of battery energy storages to the energy management systems. There can be conflicts with the maintenance functions of the batteries, which would have to be re-programmed (after agreement with all the stakeholders) so that they can be used with higher level control layers.
- Technical difficulties in integrating heterogeneous controllable devices. Interoperability of those devices is not straightforward due to their different communication protocols (that run on top of the Internet protocol) or due to their different response times in control commands from the energy management systems.
- Other challenges of social nature that affect field tests e.g., coordination and agreement among all stakeholders that are associated with the devices and the control systems on different levels. The effectiveness of communication and coordination is critical at multiple phases of the project (e.g., preparation, preliminary testing, final demonstrations).

What is the next step to take the research results further?

It is critical for the DSOs to conduct field tests in order to understand the compatibility of the technology. It is also important that they conduct planning studies in order to modify their traditional business models and accommodate the interaction with the microgrids. This will allow the system operators to take advantage of the benefits resulting from coordinated interaction with the MGs. These planning studies should consider both DSOs and third parties as MGs developers to explore the benefits indicated by the project’s results and the different coordination schemes between MGs and DSOs.

In order to test coordination with third-party MGs developers the DSOs should also specify the information they would like to receive from the MG operators as well as the frequency update of the specified data. The DSOs could also help to deal with interoperability issues by specifying and promoting the use of a single communication protocol that runs on top of TCP/IP. This could speed up the standardization process and would facilitate field tests with multiple third-party MGs or MG resources from different vendors.

Regarding the local and flexibility markets, the project has also contributed to the process of clarifying the strengths and weaknesses of different market options. The results from the market modeling and simulations have increased the understanding of specific challenges related to distributed markets, as well as the overall understanding of the complexity of interactions between markets of different designs. However, in order to fully take advantage of the future distributed energy landscape through market approaches, an increased understanding of the complex relations between different market design elements must be further analysed.

Which target groups should see the results of the project?

Two main stakeholders were identified in this project:
1. Distribution system operators.
2. Microgrid operators e.g., property managers, communities, end-users that own both local energy sources and energy storage, third-party developers that offer energy or flexibility services through microgrids, aggregators of distributed energy resources.

Other stakeholders include:
- Electricity consumers
- Technology providers (e.g., battery manufacturers, manufacturers of converters)