Savings
Time-of-Use Rates: How Batteries Save Money
Charge off-peak, discharge on-peak — when a home battery pays for itself beyond backup alone.
7 min read · Beginner
The simple arbitrage loop
On TOU plans, electricity is expensive in the evening peak and cheap overnight or midday with solar. A battery stores cheap energy and covers expensive hours.
Backup vs bill savings
If you only care about outages, a smaller critical-load bank may be enough. If your utility has a steep peak rate, a larger bank can cut more of the bill — run numbers with your actual rate schedule.
Round-trip losses
Expect roughly 8–15% energy loss through charge and discharge. Savings still work when the peak/off-peak spread is wide enough to overcome that loss.
Related manuals & docs
Manufacturer PDFs that pair with this topic.
- OpenmanualEG4
EG4 WallMount All-Weather — User Manual
Full install, paralleling, conduit box, and BMS setup for outdoor WallMount packs.
- Openquick startEG4
EG4 WallMount All-Weather — Quick Start
Fast mounting overview with 18kPV / FlexBOSS bracket notes.
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