Understanding battery energy storage systems for homes

How battery energy protects your home

BESS are changing the way homes use and manage electricity. These systems offer a smart, easy way to cut costs, use more clean energy and maintain reliable backup power for your entire home. In this guide, we’ll break down what a BESS is, how it works and how you can take advantage.
 

What is a BESS?

A BESS is much like a large-scale version of the batteries we already use throughout our lives. It stores energy from the power grid, as well as from renewable sources such as solar panels, and then releases it when needed.

One of its most important functions is kicking in to keep your lights and appliances running like normal if there's ever a power outage.

In addition to this backup function, a BESS can help save you money on electricity and use cleaner energy. A BESS can charge up from a home solar system, stockpiling energy when the sun is shining so it's available later.
 

How does a battery energy storage system work?

A look inside a BESS

A battery energy storage system is made up of several key parts that all work together:

• Battery modules: These are the heart of the system, where electricity is stored for later use. Most systems use lithium-ion batteries because they’re compact, reliable and long-lasting.
• Inverter/converter: This device is part of the power conversion system and is designed to switch electricity between direct current (DC) and alternating current (AC).
• Battery management system (BMS): Think of this as the brain of the setup. The BMS monitors the battery’s performance, keeps it operating safely and prevents issues like overheating or overcharging.
• Cooling and safety systems: These systems do the work of maintaining temperature in the BESS to ensure that it operates safely, especially during high energy use or in warmer climates.
• Energy meter: This tracks how much electricity is coming in from the grid or solar panels and how much is being stored or used.

Solar panels: Many systems pair with home solar systems, making it possible to store your own clean power for later use — especially at night or during outages.
 

How software makes your battery smarter

Smart software is what turns your battery into an energy-saving machine. It helps the system decide the best time to charge or discharge energy based on certain metrics, which may include:

• Current electricity prices and demand on the power grid
• Weather conditions and solar panel output forecasts
• Your home’s typical energy usage patterns

By analyzing and leveraging this data, BESS software can extend the battery’s lifespan, reduce energy costs and help you take advantage of savings opportunities, like time-of-use rates or demand response programs.
 

Why use a BESS in your home?

BESSs are a smart way to take control of your home’s electricity use. There are multiple potential scenarios and use cases to consider, any of which may apply to your household.
 

Stay powered during outages

Power outages can be an interruption of daily life, but with a BESS, you'll be able to keep your home up and running if one should happen. A BESS can keep the lights on, run important appliances and even power your devices should the grid go down.

Enjoy being able to save money during peak hours

Electricity costs can spike during peak demand hours, such as in the late afternoon or early evening. By using energy stored in your BESS during these peak periods, you can cut costs. This is called "peak shaving" and can add up to significant savings over time.

If you have a time-of-use plan, like an EV plan with free nighttime charging, you can stockpile energy during these reduced-rate periods. You can also save up energy in this way when the sun is shining on your rooftop array.

Earn rewards by helping the grid

Some programs, like Reliant Battery Perks, allow your battery to help support the energy grid during periods of high demand. In return, you can earn money or bill credits just for allowing your battery to share energy when it’s needed most. It’s a great way to be part of the solution and get rewarded for it.

Easily handle changes in the grid

As more renewable energy sources, like wind and solar, are added to the power grid, your energy supply can fluctuate with weather changes. A BESS helps balance energy consumption by storing excess energy when there’s a surplus and releasing it when there’s not enough, which leads to better grid stability.

Support sustainability and reduce carbon emissions

Battery storage makes it easier to use sustainable energy even when the sun isn’t shining or the wind isn’t blowing. By saving renewable energy to use later, you rely less on fossil fuels and shrink your carbon footprint.

How long do battery energy storage systems last?

Knowing how long a BESS can last helps you make the right choice and get the most out of your investment. With the right setup and care, your battery can keep delivering clean, reliable power for years to come.
 

Typical lifespan

Most lithium-ion battery systems last about 15 years and 6,000 to 8,000 cycles before they start to lose performance. Some of the newest models may last even longer. But with regular care and a little help from smart battery software, you can make sure your system stays strong for as long as possible.

What affects battery lifespan?

Several everyday factors can impact how long your battery lasts:

• How deeply the battery is discharged: Using smaller amounts of energy more often, rather than draining the battery completely, can help it last longer.
• Temperature: Batteries don’t love extreme heat. In hot climates like Texas, good ventilation and cooling systems help prevent wear and tear.
• Smart software controls: The system’s software helps your battery last longer by managing when it charges and discharges to avoid unnecessary wear. BESS software can also set parameters for how much of your battery gets discharged, to help preserve its lifespan.
   

How battery storage works with renewable energy

While batteries can offer a lot of value on their own, they’re even more powerful when you combine them with clean energy sources like solar.
 

Why solar and battery storage work better together

When you combine solar panels with a battery system, you can unlock even more value:

• Store extra solar energy during the day
• Use that energy at night or during outages
• Reduce your reliance on the electric grid
• Improve your return on investment from solar

This combo is growing in popularity across Texas, especially as more residents take advantage of solar incentives and want greater control over their power.

Can you use battery storage without solar?

Yes! You don’t need solar panels to benefit from a BESS. Without solar, the battery charges from the electric grid and can power your home during peak rate periods or outages.

A time-of-use plan offering reduced-rate (or even free) electricity during certain parts of the day means you can stockpile energy when it's more affordable.

Connecting to the bigger energy picture

A BESS adds even more value when part of a distributed energy resource system, such as community solar, microgrids or virtual power plants (VPPs). These systems are all about producing and sharing energy locally, which reduces demand on large, centralized power plants and makes the grid more beneficial for everyone.
 

Drawbacks of battery storage systems

Battery energy storage systems offer big benefits, but, like any technology, they also come with some notable challenges. Here are some common drawbacks to consider, and how the industry is working to address them:
 

Environmental impact of battery materials

To build batteries, materials like lithium, cobalt and nickel have to be mined. That process can raise environmental and ethical concerns.

The good news is that battery recycling is getting better every year, and more providers are working toward responsible sourcing and reuse. These include:

• Battery recycling: Recycling your batteries helps recover and reuse valuable materials that are otherwise mined. The main examples are lithium, cobalt and nickel. Instead of letting these go to waste, they can be given a second life in another energy-storing capacity. Even big brands like Tesla and Apple have introduced recycling programs to reclaim materials from old devices and electric vehicle batteries.
• Second-life batteries from electric vehicles (EVs): When an EV battery no longer holds enough charge to power a car efficiently, it still has a lot of life left — usually around 70 - 80% of its original storage capacity. Instead of being recycled right away, these batteries can be reused in energy storage systems.
• New battery types in development: Options like sodium-ion and solid-state batteries are built with common, less expensive materials that could offer better safety, lower costs and longer lifespans. Some new designs are also being made to be easier to recycle, creating less long-term waste and a cleaner battery supply chain.

Evolving rules and regulations

As more people install battery systems, the rules shaping how they connect to the grid and how you’re rewarded for using them are still taking shape. These challenges can include:

• Developing policies: Rules for battery storage can vary widely depending on your state, county or utility provider.
• Changing incentive programs: Rebates and credits for battery systems may come and go as utility programs evolve.
• Evolving standards: Battery systems need to meet local electric code and utility requirements, which may change over time.

Backup power limitations

Battery storage is great for short-term use, like keeping essential appliances running, but most home systems aren't designed to power everything for long periods. Here’s what to keep in mind:

• System size matters: Standard battery systems are typically sized to power key items, not your entire home for days.
• Need for backup generator support: Depending on the duration of an outage, additional energy solutions such as large-scale storage systems or a backup generator may be needed.

The right battery setup depends on your power generation needs. A trusted installer can help design a system that uses your power supply in the most cost-effective way possible.
 

How Reliant Energy supports your home battery storage needs

Reliant can help you make the most of battery energy storage technology, whether you’re just starting your research or ready for a full energy transition in your home.

Reliant customers get access to:

• Smart usage tracking, bill forecasting and energy-saving tips
• Helpful tools in the Reliant app that make managing energy simple
• Personalized assistance choosing trusted battery storage installers and manufacturers
   

Start storing energy in your home with a BESS

A BESS puts you in control of how and when you use electricity, and now is the perfect time to take advantage of battery energy storage in your home. Reliant is here to guide you through every step, from exploring your options to finding a trusted installer.

Ready to take charge of your home's energy? Get started, or call us at 866-222-7100.