Advanced Battery Calculator
Example Data Table
| Case | Capacity Each | Count | Critical Load | Usable AC Energy | Backup Time |
|---|---|---|---|---|---|
| Small essential load | 9.8 kWh | 1 | 900 W | 7.31 kWh | 8.12 hours |
| Medium home backup | 9.8 kWh | 2 | 1500 W | 14.62 kWh | 9.75 hours |
| Longer outage plan | 13.0 kWh | 3 | 2200 W | 29.10 kWh | 13.23 hours |
Formula Used
Usable battery energy: nominal capacity × depth of discharge × battery efficiency × temperature factor × age factor.
Total usable AC energy: usable battery energy × number of batteries × inverter efficiency.
Backup time: total usable AC energy ÷ critical load in kilowatts.
Required battery count: target backup energy ÷ usable energy per battery. The result is rounded up.
Solar recharge energy: solar array size × peak sun hours × charge efficiency.
How to Use This Calculator
Select a battery model or enter a custom capacity. Add the number of batteries. Enter the allowed depth of discharge, efficiency, temperature loss, and age factor. Then enter your daily energy demand and critical backup load. Add your desired backup hours. Include solar array size and sun hours if you want recharge timing. Press the calculate button. The result appears above the form.
Planning Solar Storage With LG Chem Batteries
Why Battery Sizing Matters
An LG Chem solar battery system can support home loads during outages. It can also store extra solar energy. Good sizing is important. A small battery may drain quickly. A large battery may cost more than needed. This calculator helps compare load demand, usable energy, and backup time in one place.
Usable Energy Is Different
Battery labels often show nominal capacity. You may not use all of that energy. Depth of discharge limits usable storage. Battery losses also reduce delivered energy. Inverter losses reduce it again. Temperature and age can reduce output too. This page includes those factors. That makes the estimate more realistic.
Load Demand Controls Runtime
Backup time depends on the critical load. A refrigerator, lights, router, and fan may need modest power. A heater, pump, or air conditioner can need much more. Enter only the loads you plan to run during backup. This gives a better outage estimate. You can also add surge load. Surge checks help flag motor starting issues.
Daily Use and Autonomy
Some users need a few hours of backup. Others want one or more days. The autonomy field expands the daily load target. The safety factor adds margin for unknown loads. This is useful for cloudy days, extra appliance use, or older batteries. A conservative design is usually safer than a perfect paper estimate.
Solar Recharge Planning
The solar recharge section estimates daily charging energy. It uses array size, peak sun hours, and charge efficiency. The recharge result shows how many days may be needed to refill the battery bank. This number changes by weather, roof angle, shading, and seasonal sun. Use local data when planning a final system.
Cost Value Estimate
The calculator also estimates energy value. It multiplies covered daily energy by your electricity rate. This is not a full payback study. It does not include battery cost, permits, labor, demand charges, or incentives. It is a simple planning value. Use it to compare different storage sizes before asking for quotes.
FAQs
What does this calculator estimate?
It estimates usable battery energy, backup runtime, required battery count, recharge time, and simple energy value for an LG Chem style solar storage setup.
Is nominal battery capacity fully usable?
No. Usable capacity is lower after depth of discharge, battery losses, inverter losses, temperature effects, and battery aging are included.
Why does inverter efficiency matter?
Most home loads use AC power. Battery storage is DC. The inverter changes DC to AC, and some energy is lost during conversion.
How do I choose critical load watts?
Add the running watts of the devices you want during backup. Include lights, refrigerator, router, medical devices, and other essential equipment.
Should I include surge watts?
Yes. Motors and compressors can need high starting power. Surge watts help you review whether the inverter and battery bank are suitable.
What is the safety factor?
The safety factor adds extra margin to your energy target. It helps cover weather changes, extra loads, and imperfect field conditions.
Can this replace installer design?
No. It is a planning calculator. Final battery design should follow battery manuals, inverter limits, electrical codes, and installer review.
Why is recharge time only an estimate?
Solar charging changes with weather, shading, roof angle, season, and system losses. Use local solar data for stronger design decisions.