Hurricane Season Battery Backup: How to Prepare Your Houston Home
Hurricane Season Battery Backup: How to Prepare Your Houston Home
On July 8, 2024, Hurricane Beryl made landfall near Matagorda Bay as a Category 1 storm. Within hours, 2.2 million CenterPoint customers in the Houston area lost power (Houston Public Media, 2024). Eight days later, nearly 100,000 households were still in the dark, in July, in Texas. At least 22 people died in the Greater Houston area from storm-related causes, and more than half of those deaths were tied directly to the outage: heat exposure and loss of medical equipment.
Beryl wasn't an extraordinary storm. That's the point. Houston homeowners don't need a Category 5 to face a week without power. You need a reliable backup plan before June 1.
Key Takeaways
- Hurricane Beryl (2024) knocked out power to 2.2 million Houston-area customers; 98,000+ were still without power 8 days later (Houston Public Media, 2024).
- Houston homes use roughly 1,300 kWh/month on average, about 30% above the national average, with AC driving 50-70% of summer electricity use (Texas Electricity Ratings, 2025).
- A 18-27 kWh battery backup keeps essential loads running for 24+ hours with AC, or 3-5 days with managed load operation.
- Install before May: lead times stretch 2-4 weeks as hurricane season approaches.
Why Houston Power Outages Last So Long After a Storm
In 2024, hurricanes caused more customer outage hours in the U.S. than any year in the past decade. Americans averaged 11 hours of power interruptions, nearly double the prior decade's average, with Hurricanes Beryl, Helene, and Milton accounting for 80% of those hours (U.S. Energy Information Administration, December 2024). For Houston specifically, the numbers are worse than the national average suggests.
Three factors make Houston outages unusually long after a major storm:
Above-ground distribution lines. Most of CenterPoint's last-mile infrastructure runs on wooden poles. High winds snap them. Flooding undermines them. Repairs happen pole by pole, neighborhood by neighborhood, and crews can't work safely until the storm fully passes.
Flat floodplain terrain. Houston doesn't drain quickly. Substation flooding after heavy rainfall can knock out power to entire districts for days while equipment dries out and is inspected. Harvey (2017) put substations underwater. Some took nearly two weeks to bring back online.
Scale. The Houston metro has roughly 5 million residents spread across a very large footprint. When 2+ million customers lose power at once, restoration is a logistical problem that takes weeks, not days.
Beryl was the wake-up call many Houstonians needed. If a modest Category 1 storm can leave nearly 100,000 homes without power for more than a week in peak summer heat, a stronger storm presents a genuinely dangerous situation for families without a backup plan.
What a Home Battery Backup Actually Does When the Grid Goes Down
A home battery backup is a wall-mounted or garage-installed rechargeable unit, typically between 9 and 36 kWh of capacity, wired into your home's electrical panel. When grid power cuts out, it switches over automatically, in under 20 milliseconds, with no extension cords, no startup time, and no fuel to find at a gas station that's already sold out.
The average Houston home uses approximately 1,300 kWh per month, roughly 30% above the national average, with air conditioning accounting for 50-70% of a typical summer electric bill (Texas Electricity Ratings, 2025). That high baseline is exactly why sizing matters more in Houston than in almost any other U.S. city.
What the battery typically covers during an outage:
- Refrigerator: roughly 1.5 kWh per day, keeping food safe for the full outage
- Window or mini-split AC (1.5-ton): roughly 1.5 kWh per hour of runtime
- LED lights and phone charging: minimal draw, essentially negligible
- Medical equipment (CPAP, nebulizer): 0.1-0.5 kWh per night, device-dependent
- Internet router and modem: roughly 0.05 kWh per hour
What it doesn't replace: your entire home running at full capacity. It's designed to keep your family safe and functional, not to replicate normal operation with laundry running and every light on.
How to Size a Battery System for Your Houston Home
For most Houston homes, a system between 18 and 27 kWh provides 12-24 hours of runtime with AC running continuously, or 3-5 days if you cycle the AC and manage loads carefully. Here's how to think through it.
Step 1: List your critical loads. What do you absolutely need during an outage? Most Houston families land on the same short list: one AC zone (the primary bedroom or living area), the refrigerator, phone and laptop charging, lights, and any medical equipment.
Step 2: Estimate daily draw. One 1.5-ton AC unit running 12 hours a day uses about 18 kWh. Add the fridge (1.5 kWh/day) and lighting (under 0.5 kWh/day). Your minimum daily draw in a Houston summer, for modest comfort, is roughly 20-22 kWh.
Step 3: Match capacity to your scenario.
| Battery Capacity | Best For | Est. Runtime (Critical Loads + AC) |
|---|---|---|
| 9 kWh | Lights, fridge, devices only | 8-12 hrs |
| 18 kWh | Essential loads + one AC zone | 20-24 hrs |
| 27 kWh | Whole-home critical loads with managed AC | 2-3 days |
| 36 kWh | Work from home, medical equipment, extended outages | 3-5 days |
If someone in your home relies on a medical device, or if you work from home and can't afford days without power and internet, size up. The cost difference between a 27 kWh and 36 kWh system is considerably smaller than a week in a hotel with your family.
For the full sizing math, see how to size a home battery for a Texas home.
Battery Backup vs Generator: Which Wins for Hurricane Season?
Generators offer longer raw runtime, in theory. But there's a real problem after a major Houston storm: gas stations sell out within 24-48 hours of landfall, and fuel delivery trucks can't reach flooded roads. A generator without fuel is an expensive anchor.
A University of Houston survey of 2,257 residents conducted after Hurricane Beryl found that only 26% had purchased or maintained a generator, yet most still experienced multiple days without power (University of Houston, Hobby School of Public Affairs, July 2024). That same survey found 57% of Houstonians had considered leaving the region due to extreme weather. The outages aren't just an inconvenience. They're a quality-of-life crisis that shapes whether people stay.
Here's how battery backup and generators compare on the factors that matter most during a Houston summer outage:
| Factor | Battery Backup | Portable Generator | Standby Generator |
|---|---|---|---|
| Fuel required | None (grid or solar recharge) | Gasoline (scarce post-storm) | Propane or natural gas |
| Carbon monoxide risk | None | Yes, outdoor only | Minimal |
| Noise | Silent | Very loud | Moderate |
| Auto-switchover | Yes, instant | No | Yes |
| Runtime per charge/fill | 12-84+ hours | 8-12 hours per tank | Days, if gas line is intact |
| Annual maintenance | Minimal | Required | Required |
Battery backup wins for the first 1-3 days of an outage, which is when conditions are worst and fuel is hardest to find. A standby generator connected to a natural gas line is the stronger option for very extended outages, but costs $10,000+ installed and depends on the gas supply staying intact through the storm.
Step-by-Step: How to Prepare Your Home Before Hurricane Season
Battery backup works best when you've taken a few intentional steps before a storm is named. Here's the pre-season checklist from the Eos installation team.
1. Schedule your installation before May. Lead times for battery installations stretch to 3-4 weeks as June 1 approaches. Book in March or April. The installation itself takes 1-2 days once your equipment arrives.
2. Audit your critical loads. Walk through your home and list what you absolutely need during a week-long outage: primary bedroom AC zone, refrigerator, one TV or laptop, phone chargers, and any medical equipment. That list determines which circuits your installer includes in the backed-up panel. It's also worth knowing how long food stays safe in a fridge without power so you can plan your load priorities.
3. Charge to 100% when a storm watch is issued. Most battery systems maintain a partial charge reserve in normal operation to extend long-term battery life. Before a storm, override that. Switch to manual full-charge mode 48 hours before projected landfall, while your utility power is still stable.
4. Confirm your essential-loads panel configuration. Have your installer verify which circuits are on the backed-up panel and that the automatic switchover is working. A common oversight: the refrigerator is on an uncovered circuit because it wasn't specifically noted during installation.
5. Build a load-shedding plan for extended outages. If the outage runs past 24 hours, you'll need to stretch your battery. Know in advance what to cut first: pool pump, EV charger, second AC zone, and electric water heater. Running AC in 2-hour cycles rather than continuously can turn a 24-hour battery into a 3-day one.
6. Know what to expect when power returns. When CenterPoint restores power after a major storm, voltage fluctuations are common for the first several hours. Your battery system handles this automatically, but it's useful to know your system is responding normally, not failing.
Frequently Asked Questions
How long does a home battery backup last during a Houston power outage?
It depends on system size and what you're running. A 9 kWh system covers lights, phone charging, and the refrigerator for 8-12 hours. A 27 kWh system runs one AC zone plus essential loads for roughly 60 hours. With solar panels recharging during daylight hours, runtime extends well beyond what the battery alone provides.
Can a home battery backup run an air conditioner in a Texas summer?
Yes. A standard 1.5-ton AC unit draws roughly 1.5 kWh per hour. An 18 kWh battery runs it continuously for about 12 hours, or 24+ hours if you cycle it on and off and raise the thermostat setpoint to 78-80 degrees. For a 27 kWh system, managed AC operation is sustainable for 2-3 days without any recharging.
How long did Houston lose power after Hurricane Beryl?
Hurricane Beryl knocked out power to 2.2 million CenterPoint customers at peak on July 8, 2024. By July 16, roughly 98,000 customers were still without power, 8 days after landfall. Some neighborhoods, particularly those with above-ground infrastructure and flood damage, waited 10-14 days for full restoration (Houston Public Media, 2024).
Is a home battery or generator better for hurricane prep in Houston?
Battery backup wins on safety, noise, and convenience, especially for the first 72 hours when fuel is scarce and outdoor conditions are dangerous. A standby generator offers longer raw runtime if you have a dedicated propane or natural gas supply. For most Houston homeowners, an 18-27 kWh battery handles the critical window when it matters most.
When is the best time to install a battery backup before hurricane season?
Before May 1. Hurricane season runs June 1 through November 30, and installation lead times grow quickly once April ends. The installation itself takes 1-2 days, but equipment availability and scheduling mean starting the conversation in March or April gives you the most options and the best pricing.
Don't Wait for a Named Storm
Houston's track record is clear. Ike took three weeks to fully restore. Harvey took 12 days in the hardest-hit flood zones. Beryl, a modest Category 1 storm, put nearly 100,000 households in the dark for over a week in July heat, and killed people.
The outages aren't getting shorter. The grid has improved since Beryl, but it still depends on above-ground infrastructure that high winds will always threaten. A properly sized home battery backup requires no fuel, produces no fumes, and switches over before you notice the lights flicker. It keeps your family safe through the first critical days when conditions are worst and help is hardest to reach.
The best time to install was before last hurricane season. The second-best time is now.