Optimised Residential Battery Energy Storage Systems (ORBES)

Project facts

Project promoter:
Tallinn University of Technology(EE)
Project Number:
EE-RESEARCH-0010
Status:
Completed
Initial project cost:
€750,536
Final project cost:
€736,378
Donor Project Partners:
Norwegian University of Science and Technology(NO)
Other Project Partners
Kaunas University of Technology(LT)
Riga Technical University(LV)

Description

The growing market of small-scale residential renewable energy generation and storage systems, instigates the research and development of energy management methods to handle the problems connected with necessity of delivering and storing more electric power as well as to attain more optimal use of resources and ensure security of supply. The project is focused on the area of small-scale residential battery storage, which currently lack flexible energy management systems that can enable their effective coordination and optimal utilisation of their potential. The project aims to address this problem from multiple levels: electronic components, power electronic interfaces and system-wide energy management algorithms. By performing comprehensive analysis and optimisation of the battery energy storage systems at various levels, it possible utilise the most accurate data and deliver high-quality results.

The models for forecasting of the electricity demand and supply in the Baltic Sea region from renewable energy sources will allow to create and investigate the energy management profiles that will reveal operating profiles for battery energy storage systems. These profiles are going to be used for research and multi-objective optimisation of power electronic converters, particularly in terms of efficiency and cost. This work will be used as input for further development and optimisation of energy management algorithms to take maximal advantage of battery storage systems.

The work implies constant data exchange between the project partners to ensure high-relevance of the research. The outcomes will increase the awareness of the feasibility of residential battery storage systems in the Baltic Sea Region. The project will lay foundations for development and assessment of possible business models concerning DSOs, aggregators and prosumers, aiming to reduce life cycle costs, enable effective demand response programs and take the most benefits from this emerging technology.

Summary of project results

The increased contribution of renewable generation has instigated the rapid deployment of battery energy storage systems. During the project’s duration the global battery capacity installed has increased by a factor of five. According to forecasts this trend will continue in the near decade, with around one quarter of the installed capacity assumed to be residential scale. Anticipating this trend, the project was devoted to multi-faceted study of small-scale residential battery storage, ranging from power electronic converters and their critical components to control algorithms and energy management systems. The goal was to highlight the ways to make installation of these systems attractive and beneficial. This includes correct system dimensioning, elaboration of perspective control methods and reduction of power losses.

The development of power electronic converters was focused on innovative solutions for both low- and high-voltage battery storage. By utilizing the novel design approaches, a number of approaches have been studied with different levels of feasibility. Among them, several solutions with exceptional characteristics have been developed as laboratory prototypes. A study of advanced battery management methods was performed considering the conditions in Baltic Region. It was revealed that the feasibility can be improved significantly by implementing the day-ahead forecast and allowing the battery to charge from grid during off-peak hours. For example, it was estimated that with realistically dimensioned storage, it is possible to avoid electricity purchase during peak hours completely.

In the frame of the project a total of 47 publications have been published, including 20 joint publications. Four more manuscripts are currently in review. Moreover, two joint intellectual property applications have been filed, with one of them already obtained the status of patent. The project has been contributing to the works of 14 Ph.D. students from four partner universities, among those 5 students have already successfully defended. Furthermore, throughout the project duration, the obtained results have been disseminated in international symposiums, seminars, workshops, journal special issues and in local press. The findings can be used as a basis for further research in the area as well as for elaboration of mutually beneficial interactions between various stakeholders.

The applicability of the results in real-world scenarios is to be verified. However, even a brief analysis of current market status of residential storages clearly confirmed the relevance of the project topic. In 2019, when the project application was prepared, it was still an emerging market with around 15 GWh of storage globally. By the end of 2023 it reached 75 GWh and projected to exceed 400 GW/1200 GWh in 2030. Out of these, about 25% will be small-scale residential installations. The results obtained during the project will clearly serve as basis for future developments in this booming field.
One of the remarkable trends in the industrial sector is the transition to DC distribution. It is highly likely that the residential applications will follow that in the following years. With transition to DC, many power electronic conversion steps can be omitted, simplifying the devices, and increasing the efficiency. There are several corresponding initiatives and start-ups that are launched globally to address the remaining technology gaps: DC industrie 2, CurrentOS, dc.systems, DC Opportunities, etc. Recently, i3DC initiative was launched in Estonia and ORBES project was involved and supported that by co-funding events, workshops, and seminars. The findings and results obtained in the ORBES project can be used as a basis for forthcoming grant applications and developments in the area or residential dc distribution.

Summary of bilateral results

The donor partner NTNU was critically important solving one of the most complex tasks – multi-objective optimization and development of specialized components. The single stage isolated matrix converters (IMC) technology developed by TalTech have been known for some time but were lacking due to poor characteristics of conventional silicon semiconductors. Thus, transition to novel technology was critically important. Being an expert in the field of semiconductors and high-performance components, the role of the donor partner was crucial in shifting the IMC technology to a new level.

Information on the projects funded by the EEA and Norway Grants is provided by the Programme and Fund Operators in the Beneficiary States, who are responsible for the completeness and accuracy of this information.