Battery System for owners and the grid
In the project PV-host scientists want to improve decentralized storage battery technically and economically. To this end, they compare solar storage that are suitable for detached houses. They want to find out which operating strategy operates useful with a memory as possible network. The storage will not only meet their own needs of the household, but also reduce feed-in peak. This is to ensure that the network can accommodate a total of more electricity from solar installations.
|Project status||Near completion|
|Typical system size (Energy)||0,01 MWh|
|Typical system size (Output)||0,003 MW|
|Storage loss [1/d]||< 0,05|
|Example application areas||as battery storage system in combination with grid-tied photovoltaic systems or micro combined heat and power (CHP)|
|Project duration||July 2013 until May 2017|
Distributed energy generators like photovoltaics are common in many households because they became more affordable in the past years. In order to use solar electricity even when the sun is not shining home battery systems come into play. These systems additionally allow for relieving grid effects caused by high feed in rates if operated accordingly. Past research has focused on single battery technologies. In this project optimum storage technology and system configuration for this application shall be evaluated. This optimum is mainly determined by economic viability and thus ageing as well as grid usefulness.
Whereas other projects evaluate single previously chosen technologies, this project evaluates a variety of storage technologies in order to find the optimum technology. In addition, a systemic approach is chosen: not only the suitability of the battery cells is being evaluated but also an overall system optimum is aimed at, with all the components adapted to each other. As third focus the project considers the external interface to the grid: An evaluation of the effect of different operating strategies on the low voltage grid will take place.
By optimizing the system from a holistic system point of view and a technology open approach there is the opportunity of showing an economically and technologically optimum system for both user and DSO. A mix of simulations on household and grid level and experimental tests will be used in order to prepare the best possible estimate.
Optimum storage technology and sizing are characterized by optimum economic viability. An oversized storage system will be used less per storage capacity unit. An undersized storage system will age faster. Therefore, it is the aim of the project to find an optimum for different users. Optimum economic viability will have to be reached by using cost minimizing potentials. These evolve from optimum product design, innovative management strategies and use of synergies from a holistic optimization of energy storage and power electronics. In addition, the project will show whether extension of the distribution grid due to decentralized generation can be delayed or even omitted by using battery storage systems.
- analyse potentials of different storage technologies
- optimize operating strategy and storage size
- experimentally investigate influences of operating strategies on battery life time
- investigation of optimum system configurations and topologies for power electronics
- field test with prototypes
- elaboration of a system spec and a manual for optimum system sizing and operating strategies
- grid simulations and measurements help evaluate the effects of decentralized generation on the low voltage grid
The project joins manufacturer, battery experts and distribution system operator (DSO): As a manufacturer of systems for building energy technology Bosch offers solar inverters with and without storage system (Bosch Powertec) and photovoltaic systems and micro combined heat and power systems with fuel cells (Bosch Thermotechnology). Therefore, the main question to address at Corporate Research in Schwieberdingen (in the future Renningen) is which are future optimum storage technologies for distributed energy generation. The Institute for Power Electronics and Electrical Drives (ISEA) of the RWTH Aachen University works on analysing storage technologies and conducts ageing tests on selected storage technologies. münsterNETZ is the DSO of the city of Münster. In this grid ten home battery systems will be integrated and their grid usefulness will be evaluated in simulation and field test.