100ah Solar Battery Calculator

Backup Time Formula:

\[ \text{Backup Time (h)} = \frac{100 \text{ (Ah)} \times \text{Battery Voltage (V)} \times \text{Depth of Discharge} \times \text{Efficiency}}{\text{Load Power (W)}} \]

Battery Voltage (volts):

Depth of Discharge (decimal):

(0-1)

Efficiency (decimal):

(0-1)

Load Power (watts):

Estimated Backup Time:

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1. What is the 100Ah Battery Backup Time Calculator?

This calculator estimates how long a 100Ah battery will last powering a specific load, considering battery voltage, depth of discharge, and system efficiency. It's essential for solar system design and emergency power planning.

2. How Does the Calculator Work?

The calculator uses the backup time formula:

\[ \text{Backup Time (h)} = \frac{100 \text{ (Ah)} \times \text{Battery Voltage (V)} \times \text{Depth of Discharge} \times \text{Efficiency}}{\text{Load Power (W)}} \]

Where:

100 — Battery capacity in Amp-hours (Ah)
Battery Voltage — Nominal voltage of the battery (e.g., 12V, 24V, 48V)
Depth of Discharge — Fraction of battery capacity that can be used (typically 0.5-0.8)
Efficiency — System efficiency (typically 0.8-0.95)
Load Power — Power consumption of connected devices in watts

Explanation: The formula converts battery capacity to watt-hours, applies discharge and efficiency factors, then divides by load power to get runtime.

3. Importance of Backup Time Calculation

Details: Accurate backup time estimation is crucial for sizing solar systems, ensuring adequate power during outages, and protecting battery life by avoiding excessive discharge.

4. Using the Calculator

Tips: Enter battery voltage (typically 12V, 24V, or 48V), depth of discharge (0.5 for 50%, etc.), system efficiency (0.85 is typical), and total load power in watts.

5. Frequently Asked Questions (FAQ)

Q1: Why use 100Ah as the base capacity?
A: 100Ah is a common battery size for solar systems. For different capacities, multiply the result by (your Ah)/100.

Q2: What's a typical depth of discharge for lead-acid batteries?
A: 50% (0.5) for flooded lead-acid, 80% (0.8) for AGM/gel batteries to maximize cycle life.

Q3: How does battery voltage affect the calculation?
A: Higher voltage systems (24V/48V) are more efficient and can power higher loads with the same Ah rating.

Q4: What factors affect system efficiency?
A: Inverter efficiency (85-95%), wiring losses, battery temperature, and age all impact total system efficiency.

Q5: Can this be used for lithium batteries?
A: Yes, but lithium batteries typically allow deeper discharge (80-90%) and maintain higher efficiency across discharge cycles.