Pillar 2
Battery storage planning for prosumer homes
Decide what you want batteries to do, then size capacity and inverter power separately. This guide targets educated DIY and high income prosumers who care about resilience, clean backup, and future expandability.
The two decisions that matter
Decision 1: What loads are you backing up
Critical loads only, or true whole home? Most homes are happiest with a critical loads panel plus a clear plan to expand later.
Decision 2: What outcome you value most
Resilience, peak shaving, time of use arbitrage, or solar self consumption. Each implies different sizing.
Rule of thumb: capacity is about runtime. Inverter rating is about peak power and motor starts. Do not conflate them.
Battery runtime and inverter sanity tool
Use this for first pass sizing. Plug in your battery capacity and average load. Then verify surge and continuous power needs.
This will estimate runtime in hours and flag if your surge target is higher than the inverter rating you entered.
This tool is for planning. Confirm actual loads with a clamp meter, smart panel data, or utility interval data.
Storage topologies that work
Pick the architecture before you buy equipment. This determines wiring complexity, code path, and expandability.
Hybrid inverter with DC coupled battery
Efficient, clean design. Good when you want solar and storage tightly integrated. Watch vendor lock in.
AC coupled battery with existing solar
Great retrofit path. Solar remains as is. Battery system sits on the AC side with its own inverter.
Split critical loads panel with manual control
Best value for DIY. Back up what matters, keep complexity low, expand later.
Whole home with smart load shedding
Premium prosumer approach. Requires controllable loads and careful commissioning.
Key components and what they do
| Component | Why it matters | Good starting picks |
|---|---|---|
| Battery modules | Capacity and cycle life. Consider temperature limits and warranty terms. | Wall mount LFP and rack batteries |
| Battery inverter | Peak power, motor starts, and grid forming behavior during outages. | Value hybrid inverter and premium whole home inverter |
| ATS or interlock | Defines safe islanding and code compliance for backup mode. | Interlock resources and transfer gear |
| Critical loads panel | Makes the system usable. Ensures you are not backing up everything by accident. | See blueprints for a starter wiring pattern |
| Monitoring CTs | You cannot optimize what you cannot see. Consumption matters more than production. | Emporia Vue and Sense |
If you want a cleaner bill of materials, start from the blueprints and adjust to your loads.