Energy Storage
Systems

Next Generation Energy Storage.

Imagine how practical would it be to store up unused power until we really need it, or from solar panels when the sun’s not shining. And imagine charging your electric car at the times when electricity’s cheapest, from your own supply to bypass power peaks. These are not the dreams of a distant future, but can now become a reality. Our Energy Storage Systems are driving a new energy revolution, a smart technology which helps avoid performance peaks where multiple machines are simultaneously feeding off the grid. Best of all, the core of our ESS comes from upcycled electric car batteries.

Smart Energy Storage with Lithium Technology.

For all those frustrated by spiraling energy costs, we have good news for you: a system which gets around power peaks. It may sound like magic, but is merely highly sophisticated technology. We’ve developed an Energy Storage System based on buffer batteries with corresponding converters. Depending on their use cases they can be fully automatically operated, or extra energy from the ESS can be deployed elsewhere, such as for machine boot commands. The fluctuations in energy supply are familiar to all, such as solar panels producing excess energy in summer but too little in the winter, and huge disparities between electricity costs in the morning and evening. In order to save electricity and optimize power distribution, our Energy Storage Systems overcome such issues. They support grid connection whenever necessary and facilitate the dream of a wholly new circular economy.

Our competitive advantages:

  • Peak Shaving
  • Intelligent
    charge management
  • Second-life use
    of electric car batteries
  • Accumulation of own energy storage
  • Integration of renewable energies
    (wind, solar, hydro)

The Potential of Energy Storage Systems.

Electric car batteries need not be disposed of after their use - they are in fact the perfect candidate for a high-performing Energy Storage System. In this way we give them a new lease of life and put forward a viable new storage solution for industry, manufacturing, renewables, and household use.

Areas of application:

  • Industry and manufacturing
  • Electromobility
  • Building sites
    or mining
  • Telecommunications
  • Private households

Energy Storage and Management in One:
19” Lithium Battery Storage System

The 19” lithium-ion Battery Storage System caps peak loads and manages cost effectiveness at every turn. It’s a combined storage and management system, specially developed to lower your energy costs via high-performing peak shaving technology. Thanks to its universal design, the Battery Storage System can be seamlessly integrated into existing installations, such as Energy Storage Systems, ICT backup systems, or emergency power supplies for telecommunications systems.

Safe operation

The batteries are interconnected via the backplane, so that there are no live parts on the front side – an important safety consideration.

A range of voltages and capacities

Depending on the backplanes used, batteries can be connected in series, in parallel or in combination. This means systems with varying voltages and capacities can be easily configured.

Built-in Energy Management System

A 19-inch Battery Management Unit (BMU) can be integrated into the same container that controls all batteries in that rack. The BMU communicates with external devices via CAN or the e.battery systems Energy Management System, which also controls the converter in ESS applications.

Analysis and Protocols

Instant analysis is made possible thanks to internet connectivity; important information, protocols and more can be easily checked online.

Energy Storage Systems defined.

Energy Storage Systems (ESS) are core technologies in which we’ve combined our highly intelligent battery technologies to enable unprecedented energy storage. Specifically, we’re talking here about a whole range of systems for the widest possible scope of application. Whether for solar, wind or hydro renewable sources, all our Energy Storage Systems share a common goal: storing energy, smoothing out peaks, and saving power. Best of all: these Energy Storage Systems can be swiftly adapted to customer needs, down to the smallest detail. As well as battery development, we also work with the most innovative energy storage technologies. We help you improve efficiency, recognize your energy densities, and extend overall battery lifespan. Our storage systems are developed custom-made, and can be modularly extended.

Here’s how we develop customized Energy Storage solutions:

Analysis

We deep dive into the specifics of your company’s peak demands. This becomes the basis for developing a tailor-made battery storage solution.

Consultation

We give you a first impression of the technological possibilities through which you can store electricity and more efficiently put it to use.

Development

Operational performance and cost optimization begin to take shape; your customized Energy Storage System goes into the final stages of development.

Implementation

Your Energy Storage System (ESS) is ready and, depending on size, can be deployed by our team within a couple of hours.

Our USP: ESS with Second-Life Batteries.

It’s a deceptively simple concept: offering as much capacity as possible, as sustainably as possible. For us, it was clear that this should include using second-life batteries for our Energy Storage Systems, such as batteries from electric cars. With this environmentally friendly storage, it’s up to you when and for what you use your energy. The Energy Storage Systems provide you with sustainable energy reserves even at peak times.
  • The safest cell technology
  • Very low costs per stored kilowatt hour
  • Requires very little servicing or maintenance (< 1% of cases)
  • 100% supply reliability in operation
  • 5% more usable capacity
  • Ready-made for all voltages worldwide

High battery voltage
Battery voltage cannot
be switched off.
There is always danger.

ebatterysystems_icon_ess_02

100% safe low voltage
Simple and inexpensive
Maintenance and system structure.

The point of failure
A single battery failure will stop
the operation of the entire system.

ebatterysystems_icon_ess_01

Autumn operation
Failures limited to module level.
System remains operational.

Expensive waste of energy
Conventional inverters cause
significant energy losses.

ebatterysystems_icon_ess_03

70% less energy wasted
More usable energy through unrivaled
energy efficiency of the ebs ready for operation.

Static system
Battery systems can only be exchanged
be upgraded or completely upgraded.

ebatterysystems_icon_ess_05

Future-proof technology
Software-defined, modular inverters
enables the storage system to be upgraded
Years after installation.

Applications for Energy Storage Systeme.

Through smart power storage, you can have your own energy reserves to call upon and reduce electricity supply costs. Our Energy Storage Systems use innovative lithium-ion technology with minimal losses. Suitable applications can be connected to PV modules without the need for additional inverters, to store energy for later use. Installation of our ESS is quick and efficient, avoiding the costly expansion of grid networks. It can be combined equally with solar arrays, wind turbines, fuel cells, or hydropower. Depending on size, our staff can install external powerhouses or rows of cabinets in only short time.

Our ESS enable peak shaving at the start-up of devices, UPS-functionality for IT infrastructure or emergency lighting. In combination with various other systems these units can also be used for FCR (50 Hz frequency containment reserve) and congestion management. Remote control and monitoring are integrated in the Energy Storage System, and service and maintenance are straightforward yet rarely required.

Possible areas of application:

  • Building up own
    energy reserves, either
    commercially or privately
  • Emergency electricity supply
    in industrial settings
  • Stabilization of energy grids
  • Energy storage for solar panel installations
  • Private households
    (Home Storage from 30 kWh)

Energy Storage Instead of New Grid Connections.

When requiring more electricity than currently available, a new grid connection or sub-station can quickly become a costly affair. Turn instead to energy optimization, and cap your peak demands. The smart peak shaving technology in our storage systems measures and recognizes when all machines and devices need to simultaneously access power sources. It kicks in when a preset peak load is reached, selectively switching on power from the Energy Storage System. Alternatively, in certain devices or machines a start button takes over the automatic shift to the stored power.

The Main Benefits of Energy Storage

A self-sufficient
energy supply

 

Regardless of use, your own electricity supply is available for optimizing your consumption or for emergency supply.

Kicks in during
power peaks

 

The Energy Storage System recognizes power peaks and supplies the connection with additional energy from its own storage. This relieves the load on the grid connection and reduces your electricity bill.

Stores electricity
from renewable sources

 

With the ESS it’s possible to easily store green energy, by connecting with solar or wind facilities.

Supply in case
of power cuts

 

Our Storage Systems can keep machines and devices running even in the face of power cuts. The ESS utilizes its stored energy, thus keeping up power supply.

Peak Shaving and Energy Storage.

When a lift, crane or another power-hungry device draws peak power from your electricity connection, the costs can spiral. Our Energy Storage System supplements the current of your normal three-phase mains connection to compensate for such peaks. This provides preventative energy storage while also measuring and interpreting electricity usage. So-called peak shaving utilizes smart measuring tech and intelligent data processing that measures the energy and switches on one or more converters as required. This is all done fully autonomously - there’s no need to do any switching yourself or check on the charge state of the batteries, as the integrated controller takes care of everything for you.

How does our Energy Storage System work?

Put simply, each peak is met with electricity from the ESS rather than the power grid. In order to accurately measure these peaks and react appropriately, an incredibly fast processor is integrated into the ESS’s main system. This processor recognizes any increase and rapidly reacts when a threshold is reached. The converter then receives a command to deliver supplemental power from the Energy Storage. In applications where this is not possible, a further processor is employed. An additional starting switch then starts the machine and directly controls the converters. Setting the correct parameters in the integrated control system prevents peaks or overloading of the main connection that might otherwise incur additional costs. The Energy Storage System is based on buffer batteries and a 30-kilowatt converter, which can be optionally upgraded with up to three converters to achieve additional performance. The standard 32.5 kilowatt hour battery pack can be expanded in 32.5 kilowatt hour increments, all housed in a 19" cabinet and fully controlled by the e.battery systems Master Controller.

Typical applications:

  • Interception of peak power
    during machine start-up
  • Buffering for electric vehicle
    charging with PV optimization
  • Reduction of contracted
    grid costs
  • Peak power supply in combination
    with fuel cell and diesel generators
  • Optimization of grid power usage

Energy Storage System: Design

The STABL power inverter is a modular multi-level inverter for battery storage. The technical principle behind it is to dynamically connect the various DC voltage sources (battery modules) in series or bridging. This enables the generation of a step-based sinusoidal voltage, or other voltage forms as required. When turned off, the switches are open so that there is no electrical connection between the battery modules.

Operating principle for the generation
of stepped output voltage:

ebatterysystems_ess_inverter

The graphic illustrates the process of generating output voltage with the example of four modules with module voltage of 48 volts. It is modularly designed so that each voltage stage (one or more permanently connected battery modules) receives a performance board of STABL energy via a STABL module. The STABL inverter and the e.battery systems battery module form a grouping – an active module – which is self-contained. The active module has two outputs for the neighboring active module and a further connection used for communication and power supply of the electronics.

Wiring of battery module with STABL
electronics to form an active module:

ebatterysystems_ess_inverter_03

This diagram illustrates how the battery module and STABL modules are connected.

Each STABL module communicates separately with the battery module, with the STABL acting as master in the communication bus and regularly requesting status as required. Status estimation takes place in the BMS, but charge status can also be implemented in the STABL electronic module as required. The STABL modules serve as a gateway to send the BMS data to the STABL master controller, where it is then considered in the higher-level control. Management takes place via a master controller, which based on the available data determines the dynamic connection of the active modules and sets the respective voltage level at the output.

Comparison of the generated step voltage (this example: 11 steps)
of the STABL inverters and grid sine:

ebatterysystems_ess_netzsinus_stabl_step_voltage

In addition to controlling the active modules, the master controller is also responsible for synchronizing the output voltage with the mains and determines the effective current of the system. The voltage and current measurement on each STABL module and at the inverter output are also integrated. The output measurement by the analog front-end (AFE) board is designed for grid-parallel operation to ensure grid synchronization. This ensures that the AC voltages of the inverter and the mains are synchronous and that the contactors can be safely closed. As with conventional PWM inverters, a large grid filter is required to limit the currents and keep the THD within the permissible range. In comparison, however, the grid filter for the STABL inverter can be of smaller dimensions.

Electrical Wiring of the Battery System:

ebatterysystems_ess_inverter_02

With a discharge voltage of 40 V, a minimum of nine battery modules are required to ensure a connection to a 230 V grid sine. To test the reliability in the event of a battery module fault, an additional, redundant battery module is required in the affected string so that the remaining battery modules can compensate for the failure. In this case, one battery module is inactive at a time. The respective inactive battery module is changed several times per minute to ensure an even load and an even state of charge of the battery modules. Without a redundant active module, the power is reduced in the case of such a fault and the THD is no longer standard-compliant.

Energy Storage System: Examples

The essential function of the ESS is to optimize energy consumption. In many production processes, energy consumption is relatively low, but occasionally heavy loads have to be moved, using lifting gear which can consume a lot of electricity and drive up costs. Our innovative peak shaving system can reduce these costs. If additional forklifts are required in a warehouse, this usually means more grid power is needed. If cost constraints make this difficult, peak shaving system is here to help. Forklifts with lithium batteries require a higher charging current, and the cost-effective alternative is a battery buffer. But other machines also consume a lot of energy, such as for molding plastic. In this case, heating systems provides a relatively constant output, but extruders are power-hungry. Such a peak can be bypassed with an Energy Storage System to optimize available battery capacity.

30 kW / 120 kW System:

For applications in this power range, a 19-inch cabinet with a 30-kW converter and 13 batteries (35 kilowatts) can be used. Multiple converters, both grid-dependent and off-grid, are connected in parallel so that Energy Storage Systems of up to 120 kilowatts can be configured.

Larger Systems (> 120 kW):

These can be configured on request and often end up as complete Energy Storage Systems which can be built into their own cabinet. Fast meters measure the power consumption and transmit the signal when the system starts. As this often involves large capacity but relatively low energy demand, the systems can also be used to store PV and wind energy to generate additional revenue.