Home batteries, explained — honestly.
No jargon, no hype. Straight answers on whether a home battery makes sense for your home — from someone who actually runs one (here in Charleston, on Dominion Energy).
Start here
Is a home battery worth it?
It comes down to two things: how much outages disrupt your life, and whether your utility offers a time-of-use rate you're willing to switch to. On a standard flat rate, a battery on its own won't lower your bill much — but it keeps you powered through storms, and paired with a rate-plan switch (or solar) it can save real money every month. (Here in Charleston that switch is Dominion's Rate 7 — more on that below.)
The honest answer is bill-specific — a generic “you could save!” number is meaningless. That's the whole point of the analyzer: it runs your actual usage.
Resilience
Staying powered through outages — and hurricanes
If you live anywhere storms knock the power out — and along the hurricane-prone Southeast coast like here in Charleston, that's often — a battery earns its keep. Unlike a generator, it kicks in automatically and silently the instant the grid drops: no fuel to fetch, nothing to start.
What matters most to keep running, roughly in priority:
- Fridge & freezer (saving your food)
- A few lights and phone/device charging (light + staying reachable)
- Internet / Wi-Fi (info during the storm, working from home)
- Medical devices — CPAP, oxygen — if anyone relies on them
- For flood-prone homes: your sump or septic pump
- Cooling — a window unit or mini-split runs for hours; central AC and electric water heating drain a battery fast
The trick is planning for the loads that matter most, not running the whole house at once.
Compared
Battery vs. generator — the honest version
Both keep the lights on. They're just good at different things.
Home battery
- Silent, automatic, safe indoors
- No fuel, no maintenance
- Can save money daily by shifting usage
- Higher upfront cost
- Finite runtime per charge (recharges from grid or solar)
Generator
- Cheaper upfront
- Runs as long as you have fuel — good for long multi-day outages
- Needs gas/propane on hand & maintenance
- Loud; produces carbon monoxide (outdoor use only)
- No everyday savings
Most people who want quiet, automatic backup and a lower bill go battery; a generator wins if you mainly need cheap, unlimited multi-day runtime.
The money part
How a battery actually lowers your bill
Here's the part most sites get wrong: on a standard flat rate, a battery by itself saves almost nothing. The savings come from switching to a time-of-use rate — if your utility offers one. Power is cheap overnight and expensive during a peak window; your battery charges when it's cheap and runs your home during the pricey window, so you buy very little at the high rate. Add solar and you store your own daytime power to use at night.
Here in South Carolina, that switch is moving from Dominion's standard plan (Rate 8) to its time-of-use plan (Rate 7) — and a battery is what makes it pay off. Whether your own utility has an equivalent depends on where you live, which is exactly what the analyzer sorts out for you.
In plain English: charge when it's cheap, use it when it's expensive.
Sizing
What size do I need?
Two questions drive it: what you want to back up (and for how long), and whether you'll add solar.
As a rough feel, a ~20 kWh battery keeps the essentials — fridge, lights, Wi-Fi, a window AC — running about 10–14 hours. Heavy loads like central AC, an electric range, or an electric water heater need a bigger system. The analyzer gives you a starting range from your real usage; a licensed installer confirms the final size.
Be careful
The tax-credit truth (2026)
You'll still see sites advertising a 30% federal credit on home batteries. For a 2026 purchase, that's a dead rule. The residential clean-energy credit (§25D) that covered home batteries ended for systems placed in service after December 31, 2025.
If you buy with cash or a loan in 2026, there's no federal credit. Lease or PPA financing can still reach up to 30% through a different (commercial, §48E) credit — but that flows through the installer, not your tax return. We show you the correct number, even when it's the worse one. That's the whole point of being the trustworthy source.