A few years ago, whole-home battery backup systems existed, but they were expensive and difficult to expand when homeowners needed more capacity, and they often locked homeowners into a single brand. That has changed quickly.
The cost of residential lithium iron phosphate (LiFePO4) battery storage has dropped significantly over the past two years. At the same time, manufacturers have introduced modular systems that let homeowners start with a smaller battery and add more storage later as their needs or budget change. After spending several months with one of these systems in my own home—the Anker SOLIX E10—I think this is a feature every real estate agent should understand.
Why Today’s Systems Are Different
The biggest change is flexibility. The SOLIX E10 starts at about $4,299, and homeowners can expand the system over time by adding additional battery units instead of replacing the entire system. A single unit can store up to 30 kWh of electricity, and multiple units can be combined for even greater backup capacity. The system is also great because it:
- meets key safety certifications
- automatically switches on during a power outage in about 20 milliseconds
- works with rooftop solar
- can connect to Anker’s tri-fuel Smart Generator, which runs on gasoline, propane or natural gas
The important takeaway for buyers is that they no longer have to choose between investing in a large, expensive battery system or not having backup power at all. They can install a system that fits both their home and their budget and then expand it later if their needs change.
How the System Works at Home
My own setup is more complex than what most homeowners will have. Our home in Minnesota’s Twin Cities already has rooftop solar, two EV chargers and an off-peak utility program. Because of how our utility handles solar power, excess electricity is sent back to the grid for credit instead of charging the battery directly. Our battery system charges from the electric grid or from the backup generator during an outage.
We installed two batteries, an inverter, a smart electrical panel and the tri-fuel generator. Since the batteries couldn’t be installed inside our finished living space, they were mounted on an exterior wall, which the system is designed to accommodate.
Installation took one day and was coordinated entirely by Anker. That’s a notable improvement over earlier systems, which often required homeowners to coordinate multiple contractors themselves.
Choosing What Stays Powered
One of the most important parts of installation is deciding which parts of the house will receive backup power during an outage. The system allows homeowners to prioritize up to 12 electrical circuits. We chose essentials like the furnace, sump pump, refrigerator, air conditioner, microwave, internet equipment, garage door opener and several lights.
This is also the easiest way to explain the system to buyers. Rather than trying to power the entire house, homeowners typically choose the features they cannot live without during an outage, such as heating or cooling, refrigeration, communications and equipment that protects the home from damage.
With our current setup, two batteries provide about 12 hours of backup power for those essential systems. That’s a number that buyers typically always ask about, but the answer depends on how much electricity they’re using and which appliances they choose to power. The advantage of a modular system is that homeowners can increase that runtime later by adding more batteries or relying on the backup generator.
The accompanying app also makes the system easy to manage. Homeowners can monitor how electricity is flowing between the utility, solar panels, batteries and the home in real time. It can also automatically fully charge the batteries when severe weather is forecast, ensuring backup power is available before a storm arrives.
Why It Matters for Resale
What does this mean for resale? More than it did even a year ago.
Recent industry data suggests homes with battery storage can command meaningful price premiums and often spend less time on the market than comparable homes without it, particularly in areas that experience frequent power outages, wildfire-related shutoffs or high electricity costs.
Just as importantly, buyers are beginning to view battery backup as another desirable home feature alongside solar panels, EV chargers and smart home technology. A modular battery system is a tangible, photographable feature you can put on the MLS—alongside the solar array, the EV chargers and the smart panel—and it tells a story about the home that resonates with the next generation of buyers.
It also matters that the SOLIX E10 is a professionally installed, UL-certified system that is designed as a permanent part of the home. That makes it very different from portable battery packs or DIY backup systems and gives buyers greater confidence during inspections and appraisals.
What Agents Should Know
For agents, the takeaway is the same one I made about EV chargers five years ago: Get ahead of the trend.
You don’t have to become an energy expert, but it’s important to know the basics. Learn the vocabulary—priority loads, transfer time, kWh of usable storage, AC- versus DC-coupled solar—well enough to answer buyers’ questions comfortably. Learn what parts of the home the system powers during an outage, how long the backup lasts and whether additional battery capacity can be added later.
When listing a home with battery backup, ask the seller for the system documentation, warranty information and a list of the circuits covered during an outage. Include those details in your disclosures and listing remarks. When touring new construction, ask whether the home is already designed to accommodate a future battery system.
As prices continue to fall and installation becomes more flexible, whole-home battery backup is moving from a luxury upgrade to a mainstream home feature. Agents who understand the basics will be better prepared to answer buyers’ questions and highlight a feature that is becoming increasingly valuable.
