The 300Ah lanpwr battery will provide 3.84kWh of effective energy storage capacity (DoD 90%) in a 12V system. When used with a 3kW photovoltaic array, the daily power output is approximately 12kWh (with a maximum of 4 hours of solar irradiance), which theoretically can power the off-grid load throughout the day. From normal loads of a house (0.2kW for fridge, 0.3kW for lights, and 1.5kW for air conditioner), this battery can provide full-load power for 7.6 hours (for 2kW total load) without the support of the sun. When supported by solar daytime charging, it will provide 24-hour power supply (9.6kWh day-time charging and 7.68kWh night-time use). The actual test results of an off-grid house in Freiburg, Germany, demonstrate that the 300Ah lanpwr battery still maintains an energy storage efficiency of 86% at winter (with a 2.5-hour average daily light reception), the photovoltaic consumption rate increases from 68% to 91%, and the grid reliance decreases to 9%.
The lanpwr battery features steady performance under extreme temperatures. It can supply 87% of capacity at -20℃ (compared to the 42% for lead-acid batteries), and its own self-heating mechanism (8W power consumption) recovers the charging efficiency from 38% to 75%. For the 2023 Alaska Polar Research Station application, this battery powered a 1.8kW unit (heater + comms) for 10 hours. Capacity attenuation at the night temperature of -35℃ was as low as 3.2%. UL 1973 certification testing shows that its capacity remains at 82% after undergoing a high-temperature test of 2000 cycles at 50℃, and the standard deviation of charge/discharge efficiency is ±1.8% (±12.5% for lead-acid).
In terms of cost, the initial investment of lanpwr batteries is €1,800 (€900 for lead-acid batteries), whereas the cost of electricity per kilowatt-hour (LCOE) over the life cycle is just €0.05/kWh (€0.23/kWh for lead-acid batteries), at a saving of €980 in maintenance costs over 10 years. A user example in the US, Arizona, shows that when a 5kW solar photovoltaic installation and 300Ah battery are used, the average amount of grid power purchased annually from the grid decreased from 4,200kWh to 520kWh, saving money on electricity bill payment by 1,456 (at a rate of 0.35/kWh), and the payback period fell to 4.2 years (with tax credit allowance 30%).
The actual load matching must take the loss in efficiency into account. The inverter loss of conversion (about 7%) reduces available energy to 3.57kWh. In case of a load which includes a 2kW induction cooker having 1 hour average daily utilization, another two sets of lanpwr batteries (total of 600Ah capacity) would need to be added to service peak demand. An example from a South African campervan project shows that when 300Ah battery is charged by a 1.5kW air conditioner and a 0.5kW appliance, the battery life decreases from 8 hours to 5.2 hours. However, with daytime photovoltaic charging (3.84kWh charged over 4 hours), it can still meet the requirement for the day.
Sophisticated management improves efficiency. lanpwr’s Bluetooth BMS permits real-time adjustment of charging and discharging limits. Using time-of-use electricity rates (e.g., €0.12/kWh off-peak charging), a Dutch consumer experience shows that the annual cost of electricity has dropped by another 18%. The modularity allows extension to 1200Ah (4 parallel sets), permitting a 10kW inverter to drive heavy equipment (e.g., a 3kW water pump), with an efficiency fluctuation of ±0.5% (±5% for lead-acid). In case of the 2024 California wild fire emergency, a 300Ah battery powered a medical camp (load of 2.4kW) for 14 hours. With photovoltaic support, it became zero grid dependent, and the ROI of the system was 23%.