Battery Energy Storage Systems
What Is a Battery Energy Storage System?
A battery energy storage system (BESS) stores electricity so it can be used when you need it instead of only when it is generated. For homes and businesses, batteries can provide backup power during an outage, store excess solar production, reduce reliance on the electric grid, and help manage when electricity is purchased or consumed.
Battery systems can be installed with a new solar array, added to an existing solar system, or installed as standalone energy storage. The right system depends on what you want the battery to accomplish, how much energy you use, the electrical loads you want to support, and the amount of storage capacity you need.
Choosing the Right Battery System
Battery energy storage is not one-size-fits-all. Some systems are designed primarily for whole-home backup, while others offer greater flexibility for solar integration, load management, system expansion, or commercial applications.
BD Electrical & Solar designs and installs residential and commercial battery energy storage systems throughout Massachusetts. Understanding the differences in battery capacity, power output, chemistry, system architecture, and backup capabilities is the first step toward choosing the right system for your property.
What Do You Want Your Battery to Do?
Backup Power
Keep your home or essential electrical loads powered when the utility grid goes down. A properly designed battery system can automatically provide backup power to critical loads such as refrigeration, heating equipment, lighting, internet, well pumps, and other important circuits. Larger systems can be designed for whole-home backup and longer-duration outages.
Store Solar Energy
Solar panels often produce the most electricity during the middle of the day when your home may be using relatively little power. Battery storage allows you to capture that excess solar production and use it later in the evening, overnight, or during an outage instead of sending all of that energy back to the grid.
Energy Management
A battery can do more than provide backup power. Smart energy management allows the system to determine when electricity should be stored, used, or supplied by the grid based on your energy consumption, solar production, electric rates, peak periods, and utility programs. This can help you use energy more strategically throughout the day.
Commercial Energy Storage
Commercial battery systems can help businesses manage electricity costs and control how energy is used. Systems can support demand-charge reduction, peak shaving, solar energy storage, utility programs, facility load management, and resiliency. Commercial BESS can range from smaller behind-the-meter systems to large-scale installations.
Which Battery System Is Right for Me?
Most modern battery energy storage systems use one of two basic architectures: AC-coupled or DC-coupled. Both can provide reliable energy storage and backup power, but they integrate with your solar and electrical system differently.
Understanding that difference can help determine which approach makes the most sense for your home or business.
AC-Coupled Battery Systems
An AC-coupled battery uses its own inverter to convert AC electricity into DC electricity for storage and back into AC electricity when the battery supplies power.
Because the battery operates somewhat independently from the solar inverter, AC-coupled systems can be particularly well suited for adding storage to an existing solar installation.
Best for:
- Adding batteries to existing solar
- Retrofit installations
- Modular expansion
- Flexible system design
- Projects using separate solar and battery equipment
Examples: Enphase IQ Battery and FranklinWH
DC-Coupled Battery Systems
A DC-coupled system connects the solar array and battery on the DC side of the system, typically using a shared or integrated inverter. Solar energy can be stored in the battery before being converted to AC electricity for the home or business.
This architecture can reduce power conversions and provides a highly integrated approach to solar and battery storage.
Best for:
- New solar + battery installations
- Whole-home backup
- High-power applications
- Integrated solar and storage design
- Maximizing solar energy utilization
Examples: Tesla Powerwall 3 and SolarEdge Home Battery
Find the Right Battery for Your Home or Business
Every home and business has different energy needs. The right battery energy storage system depends on your electrical loads, solar production, backup power requirements, utility rates, and energy goals.
BD Electrical & Solar designs and installs residential and commercial battery storage systems throughout Massachusetts. Our team evaluates your electrical system and energy usage to determine the right battery technology, storage capacity, and system architecture for your property.