Are you wondering how battery energy storage works? Click here for the ultimate guide to battery energy storage to get your questions answered.
With a global market of about $50 billion, batteries are essential to the modern world. They make it easier to carry energy and power devices anywhere.
There are increasing concerns about battery energy storage. The concerns mostly focus on batteries that can power energy-intensive devices and last longer.
Understanding how a battery energy storage system works is important for stakeholders in the energy industry. Learning more about the system components can prepare you for real-life incidents with batteries. In more detail, let's break down everything you should know about this topic.
A battery energy storage system (BESS) helps store energy from the electric grid or solar arrays. The stored energy can power appliances or devices in a home or business.
An energy storage system works in both rechargeable and disposable batteries. For disposable battery options, the system only stores power to a certain threshold. Afterward, you will need to get new batteries.
In the case of rechargeable batteries, you have to charge them before they run out of power. You can monitor the amount of current left or going in from the charge controller.
High-scale commercial activities use advanced BESSs. These systems have intelligent battery software to coordinate charging and usage. The software also gives insights on how to optimize power.
Batteries are the main component of a BESS. They store chemical energy that later transforms into electrical energy to power devices.
A typical battery comprises a mix of zinc with potassium/graphite and manganese and a steel casing. The remaining components feature paper and plastic as the build materials. This is the case for encased batteries (used in phones and cars) and average household batteries.
There are several chemistries of batteries that apply to energy storage systems. But for this guide, the main focus is lithium-based systems. It's because they are the most popular of all types of batteries.
The battery in a BESS contains a fixed number of lithium cells wired in parallel and series in a frame. This way, the cells create a module that forms a rack when stacked in large numbers. The racks are the foundation of a high-power BESS, whose components are as follows:
The BMS serves as the brain of a battery system. It helps protect the battery from any kind of damage.
To do this, it ensures that the battery runs within certain parameters. These parameters include current, temperature, voltage, state of health, and state of charge.
Sophisticated BMSs feature a multi-tiered framework. The framework protects and monitors the battery in real time.
The BMS uses certain algorithms to control and balance the battery's environment. This way, it ensures the longevity and safety of the battery.
In a typical BESS, the battery system stores and delivers power as DC (direct current). Most electrical loads and systems also operate on AC (alternating current). As such, a PCS (also known as a hybrid inverter) is crucial.
Hybrid inverters are more dynamic than traditional inverters. Their means for converting power are in two directions.
This way, it's possible to convert DC power to AC and vice versa. The bi-directionality of a PCS allows a BESS to charge and discharge.
For the PCS to work well, the BMS should give it access to the battery status. That way, it will know when to discharge and charge.
The controller is the brain of the entire battery energy storage system. It tracks, controls, and safeguards all the key components of the BESS. Also, it communicates and schedules these components.
Controllers can communicate with external electric devices like transformers and meters. They do this to keep the BESS in top performance.
The multiple levels of protection in the controller serve various roles. These roles include reverse power protection in discharging and overhead protection in charging.
The HVAC system moves air between the outside and inside of the battery's enclosure. This way, it regulates the internal environment.
Good air distribution can prolong the cycle life of lithium batteries. Optimal operating temperatures also have the same effect.
The battery cells can overheat without the right thermal management. As a result, they may malfunction and degrade over time. A good HVAC system can thus improve the performance and cycle life of a battery.
The fire suppression system comes in when there's a thermal runaway. It deploys through heat detection, smoke, or gas.
When activated, the fire suppressor releases an agent to put off the fire. As a result, the battery cools down to prevent further damage.
Fire suppression systems come in different designs. It all depends on the size of the enclosure of the BESS.
The Supervisory Control and Data Acquisition System monitors and controls BESS components. It relays communications to the controller through the Programmable Logic Controller.
The SCADA liaises with the BMS to monitor the status of the battery. It can also liaise with the auxiliary meters and hybrid inverter.
Operators can issue different commands to the SCADA from the Human Machine Interface. These commands include discharging, charging, and start/stop. They can also set parameters for auxiliary systems and the BMS from there.
Most BESSs support integrations with SCADA systems from third parties. Interfaces such as the Register Map facilitate these integrations.
The SCADA can also function as an EMS. This way, it controls and schedules application activities in the BESS.
The EMS controls and schedules BESS application activity. To do this, it communicates directly with the hybrid inverter.
Through these communications, the EMS considers external data points from various things. The data points come from loads, PV arrays, transformers, and the electric grid.
An EMS determines when and how the battery can discharge power. It uses certain application specifics to play this role. These specifics include self-consumption, load shifting, and peak shaving.
Energy Management Systems also optimize the performance of the BESS. To do this, they balance battery life and application cycling data with the asset's ROI. They also consider the limitations of the PCS and BMS in the process.
The EMS can collect and dissect performance data from the BESS. This way, it's easier to report and forecast the data.
BESSs have a number of applications, both in the residential and commercial markets. Energy storage systems can work in the following ways while using batteries.
One of the most important use cases of battery energy storage in the commercial setting is peak shaving. BESSs guarantee that no electricity above a certain limit will come from the grid at peak times. As a result, they help reduce utility bills.
Battery energy storage systems also allow for load shifting. This way, businesses can shift from electricity to renewable energy when it is convenient. They can also reorganize the power sources of their devices.
The BESS serves as an emergency backup during power outages. This way, businesses can remain operational. Also, they won't incur losses related to power outages.
Energy storage systems powered by batteries are scalable and economically viable. Businesses can set them up in the form of microgrids to power their operations.
The systems also allow you to use different sources of renewable energy. So, for a business that is considering going green, they are a worthwhile investment. Investing in them can help reduce your carbon footprint at some point.
Intelligent battery energy storage systems come with automated functions. This way, your staff can focus on other tasks while the BESS runs by itself. It will only need human intervention for software updates and maintenance.
Self-consumption is a common use case for battery energy storage systems. In this case, homeowners store energy generated by their renewable energy devices in batteries. These devices may include solar panels.
The BESS can help power homes in rural areas where access to the electric grid is a problem. It can also offer a cleaner and cheaper source of electricity to low-income neighborhoods.
Modern BESSs are easy to install and configure, unlike lead-acid batteries. They are also scalable to homeowners who want to expand the reach of electricity in their properties. This way, they are an essential part of an off-grid home powered by solar energy.
Like businesses, households also enjoy emergency backup during power outages. They can power their essential devices without relying on the main grid.
A BESS adapted for a solar-powered system is seamless and safe for residential use. It's way more energy efficient and less hazardous than a small generator. The system also emits less carbon monoxide.
The components of a battery energy storage system make it efficient, valuable, and safe. They also make the system scalable and a great off-grid energy source. With background knowledge of how they work, you can know what to expect when handling them in real life.
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