Energie Speicher Planer
Bleiben Sie nicht im Dunkeln. Berechnen Sie die genaue Batteriebank-Größe für nächtliche Nutzung oder mehrtägige Notstromversorgung.
Speicherparameter
Batteriebank-Dimensionierung
Die Speicherformel
Die Batteriekapazität hängt davon ab, wie viel Energie Sie benötigen, wie lange Sie sie benötigen und wie tief Sie entladen können.
Benötigte Wh (mit DoD)
Total Wh = (Daily Wh × Days) ÷ DoD Die Division durch DoD stellt sicher, dass Sie nur den sicheren Teil der gespeicherten Energie nutzen und so die Batterielebensdauer und Zyklenzahl schützen.
Amperestunden-Kapazität
Ah = Total Wh ÷ System Voltage Die Batteriekapazität wird in Ah bei einer bestimmten Spannung angegeben. Eine 200Ah-24V-Bank speichert 4.800Wh Gesamtenergie.
How to Size a Solar Battery Bank
A battery bank stores solar energy collected during the day so you can use it at night or during cloudy periods. Getting the size right means you never run out of power during your designed autonomy window — and you don't destroy your batteries by over-discharging them. The key parameters are daily energy load (Wh), days of autonomy, system voltage, and Depth of Discharge (DoD).
Understanding Depth of Discharge (DoD)
DoD is the percentage of a battery's capacity you can safely use before recharging. Lead-acid batteries should not be discharged below 50% (DoD = 0.5) or their lifespan drops dramatically. Lithium (LiFePO4) batteries can safely reach 80–90% DoD, making them far more space-efficient per usable kWh.
Battery Chemistry Comparison
- Flooded Lead-Acid (FLA): Cheapest upfront cost. Requires regular water top-ups and venting. Maximum 50% DoD. Cycle life ~500 cycles at 50% DoD.
- AGM / GEL Sealed: Maintenance-free and spill-proof. 50–80% DoD depending on brand. Better suited to partial-state-of-charge operation than flooded.
- Lithium (LiFePO4): Premium cost but 2–4× the cycle life of lead-acid. 80–90% DoD, lighter, and no maintenance. Best long-term value for most solar installations.
Step-by-Step Battery Sizing
- Calculate Daily Wh Load: Multiply each appliance's wattage by the hours per day it runs. Sum all appliances.
- Decide Days of Autonomy: How many sunless days must the system sustain? 1–2 days is typical for grid-hybrid; 3–5 days for full off-grid resilience.
- Apply Your DoD Factor: Divide the total energy needed by your battery's DoD rating to get the required gross capacity.
- Convert Wh to Ah: Divide gross Wh by your system voltage (12V, 24V, or 48V). Higher voltage = fewer amps = thinner wire required.
- Select Battery Count: Divide the total Ah by the Ah rating of your chosen battery, then round up to the nearest whole number.