How long will a 10kW battery power a house?
A 10kW battery (assumed to be 10kWh capacity) typically powers a home for 8–24 hours, depending on energy consumption patterns. For example, a household using 1kW/hour draws power for ~10 hours at full capacity. Critical loads like refrigerators (150W) and lighting (300W) can last 30+ hours. Depth of discharge (DoD), battery chemistry (LiFePO4 vs. lead-acid), and inverter efficiency (85–95%) significantly impact runtime. Always calculate based on peak loads—a 5kW air conditioner reduces runtime to 2 hours at full draw.
What factors determine a 10kWh battery’s runtime?
Key variables include load wattage, DoD limits, and ambient temperature. A 10kWh LiFePO4 battery at 80% DoD delivers 8kWh usable energy. If your home draws 2kW continuously, runtime drops to 4 hours. Pro Tip: Prioritize energy audits—homes with ENERGY STAR appliances often halve baseline consumption.
Runtime hinges on real-time power draw. A 1,500 sq.ft. home averaging 30kWh/day (~1.25kW/hour) would deplete 10kWh in 8 hours. However, selective load management extends this. For example, powering only a 500W fridge and 300W lighting (800W total) extends runtime to 10 hours. But what if you add a 3kW water heater? The system would last just 2.6 hours. Transitionally, balancing high-wattage devices is critical.
How does battery chemistry affect performance?
LiFePO4 batteries outperform lead-acid in cycle life (4,000 vs. 500 cycles) and DoD (80% vs. 50%). A 10kWh LiFePO4 system provides 8kWh usable energy, while lead-acid offers only 5kWh. Pro Tip: Lithium batteries maintain stable voltage under load, preventing appliance brownouts during peak draws.
Consider a 10kWh lead-acid bank: its 50% DoD limitation reduces usable energy to 5kWh. Pair this with a 2kW load, and runtime plummets to 2.5 hours. Lithium alternatives, however, tolerate deeper discharges without voltage sag—critical for powering induction cooktops (3.5kW) or EV chargers (7kW). Transitionally, thermal management also plays a role. LiFePO4 cells operate efficiently from -20°C to 60°C, whereas lead-acid loses 40% capacity below 0°C. Ever wondered why off-grid cabins prefer lithium? Their resilience to temperature swings ensures reliable winter performance.
| Chemistry | Usable Energy | Cycle Life |
|---|---|---|
| LiFePO4 | 8kWh | 4,000 |
| Lead-Acid | 5kWh | 500 |
RackBattery Expert Insight
FAQs
Briefly—most central ACs draw 3–5kW, draining a 10kWh battery in 2–3 hours. Use inverter mini-splits (1–1.5kW) for efficient cooling.
How long will 10kWh power a home office?
A laptop (50W), router (10W), and LED lights (20W) totaling 80W can run for 100+ hours (80% DoD). Add a 300W printer sporadically, and runtime remains 80+ hours.