Running an RV air conditioner solely on battery power is possible but requires careful planning due to high energy demands. Most RV AC units draw 1,000–1,500W (80–125A at 12V), necessitating large lithium battery banks (300–600Ah) for practical runtime. Specialized 12V/24V DC rooftop units, like the 850W model mentioned, reduce conversion losses compared to traditional 120V AC systems. Pro Tip: Prioritize LiFePO4 batteries with ≥2,000-cycle ratings for sustained performance.
Fasta Power RG72105P Product Overview
What battery capacity is needed for RV AC?
A 13,500 BTU AC running 1 hour requires ≈1.2kWh. For 3 hours runtime, you’d need 3.6kWh storage—equivalent to 300Ah at 12V or 150Ah at 24V. Real-world example: Two 24V 200Ah LiFePO4 batteries (9.6kWh total) could power an 850W AC for ≈11 hours. Always include 20% buffer capacity for voltage drop and efficiency losses.
How do 12V DC systems compare to inverter-dependent setups?
12V DC air conditioners eliminate inverter losses (typically 10–15%), directly using battery power. The 850W unit draws 70A at 12V—manageable with 4/0 AWG wiring. Inverter systems allow standard 120V AC units but require 2,000–3,000W pure sine wave inverters. Table shows key contrasts:
| Factor | 12V DC | Inverter System |
|---|---|---|
| Efficiency | 92–95% | 78–85% |
| Startup Surge | Handled internally | Requires 2x inverter rating |
Can solar panels sustain battery-powered AC?
Solar can offset but rarely fully power AC. A 850W AC running 8 hours daily needs 6.8kWh—requiring 2,200W solar panels (assuming 5 peak sun hours). Practical setups combine 800–1,200W solar with battery storage. For example, six 200W panels + 600Ah LiFePO4 bank enables 4–6 hours AC use overnight.
What wiring and safety systems are essential?
High-current DC systems demand marine-grade cables and circuit breakers. A 70A load needs:
- 4 AWG wire for runs under 10ft
- 2 AWG for 10–15ft
- Class-T fuses (110% of max current)
Always install temperature sensors on battery terminals and use BMS-protected lithium packs.
How does AC runtime affect battery lifespan?
Daily deep cycling from AC use accelerates wear. LiFePO4 handles 3,000+ cycles at 80% DoD vs AGM’s 500 cycles. Table compares chemistries:
| Battery Type | Cycles@50% DoD | Weight per kWh |
|---|---|---|
| LiFePO4 | 4,000 | 8kg |
| AGM | 600 | 25kg |
Redway Battery Expert Insight
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FAQs
Only with massive systems—dual 15,000 BTU ACs draw ≈3,000W, requiring 600Ah at 24V (14.4kWh). Expect 2–3 hours runtime without recharge.
Do DC air conditioners cool as effectively as AC models?
Modern DC units match traditional cooling capacity—13,500 BTU models lower temps 20°F in 30 mins. Key advantage: 30–40% less energy consumption through variable-speed compressors.
