How We Picked
Home backup has different requirements than camping or van life. You're not carrying it — so weight doesn't matter much. What matters: capacity, battery longevity, AC output headroom, and reliability. Here's what we weighted:
- LFP battery chemistry — Lithium Iron Phosphate lasts 3,000–5,000+ cycles vs. ~500 for older NMC units. For home backup, where you might cycle it 10–20 times per year, this means 15–30 years of useful life vs. 3–5. We heavily favor LFP.
- Expandable capacity — Power outages in the US last an average of 4 hours, but major storms (ice, hurricane, derecho) can mean 3–7 days. An expandable system lets you start small and scale.
- AC output headroom — Your fridge compressor has a surge draw on startup. You need at least 1,500W continuous, ideally 2,000W+ for larger loads. Split-phase (240V) matters for well pumps.
- Recharge speed — Solar and wall recharge time matters for multi-day scenarios. A unit that can absorb 1,000W+ of solar input is a major edge.
For most homeowners facing outages of 1–3 days, the EcoFlow DELTA 2 Max is the right buy — good capacity, expandable, fast charging, solid app ecosystem. For serious multi-day preparedness or partial-home integration, step up to the Bluetti AC500 + B300S or EcoFlow DELTA Pro Ultra.
What Size Do You Actually Need?
Most people guess wrong — both directions. The math is straightforward once you list your loads.
Typical home backup loads
| Appliance | Watts (running) | Surge (startup) | 12-hr Wh usage |
|---|---|---|---|
| Refrigerator (cycling ~30%) | 150W | 600W | 540 Wh |
| WiFi router | 15W | — | 180 Wh |
| LED lights × 6 | 36W | — | 216 Wh |
| Phone charging × 4 | 20W | — | 120 Wh |
| CPAP (no humidifier) | 40W | — | 480 Wh |
| Laptop × 2 | 60W | — | 360 Wh |
| Basic survival load | ~320W | ~900W peak | ~1,900 Wh |
A 2,000Wh unit gets you roughly 12 hours on this basic load. For 24 hours, you need ~3,500Wh. For 3-day self-sufficiency with solar recharging, a 2,000Wh base + panels is more effective than raw capacity alone.
Our Top Picks (Ranked)
- 7,200W AC output — can run a window AC unit, microwave, and fridge simultaneously
- Whole-home integration via EcoFlow Power Kit — works with transfer switch
- Smart Generator pairing for unlimited runtime during extended storms
- EPS (Emergency Power Supply) switches to battery in under 30ms — transparent to most appliances
- 240V split-phase capable with dual units
- 2,400W MPPT solar input — fastest recharge from panels in this roundup
- 5,000W AC output covers most household needs including well pumps
- 240V/30A output for larger loads without dual-unit pairing
- Bluetti's 6-year warranty is the longest in class
- Modular B300S batteries can be added anytime — start at 3kWh, scale to 18kWh
- Best-in-class AC charge speed under $1,500 — 80% in 50 minutes
- 1,000W solar input — full recharge in ~3 hours of good sun with 2 × 400W panels
- EPS mode: switches to battery in under 30ms
- Expandable to 6,144Wh with two Smart Extra Batteries
- Solid 5-year warranty
- 3,500 LFP cycles — highest in this price bracket
- Expandable to 8,192Wh with B230/B300 battery modules
- Dual 30A charging (AC + solar simultaneously)
- Native 24V/30A output for some RV hookups
- 6-year warranty
- 4,000+ LFP cycles — longest rated battery life in this roundup
- 3,000W AC output gives headroom for larger loads
- Expandable to 12kWh with Jackery Battery Pack 2000 Plus add-ons
- Familiar Jackery reliability and warranty (3 years base, up to 5 with registration)
Side-by-Side Spec Comparison
| Model | Capacity | Max Expand | AC Output | Solar In | Battery | Warranty | Price |
|---|---|---|---|---|---|---|---|
| EcoFlow Delta Pro Ultra | 6,144 Wh | 30 kWh | 7,200 W | 1,600 W | LFP | 5 yr | $3,999 |
| Bluetti AC500 + B300S | 3,072 Wh | 18.4 kWh | 5,000 W | 2,400 W | LFP | 6 yr | $4,999 |
| EcoFlow Delta 2 Max | 2,048 Wh | 6,144 Wh | 2,400 W | 1,000 W | LFP | 5 yr | $1,299 |
| Bluetti AC200L | 2,048 Wh | 8,192 Wh | 2,400 W | 900 W | LFP | 6 yr | $1,499 |
| Jackery 2000 Plus | 2,042 Wh | 12,000 Wh | 3,000 W | 800 W | LFP | 3 yr | $1,499 |
LFP vs NMC — Why It Matters for Home Backup
This is the single most important spec decision for a home backup unit. Here's the practical difference:
LiFePO₄ (LFP) — what we recommend
- Cycle life: 3,000–5,000+ cycles to 80% — at 20 cycles/year, that's 150–250 years theoretical. Real-world: expect 15–25 years before noticeable degradation.
- Safety — LFP chemistry doesn't produce thermal runaway in the same way NMC does. Lower risk of fire or gas emission under abuse or damage.
- Temperature tolerance — holds capacity better in cold (useful if stored in an unheated garage).
- Depth of discharge — safe to discharge to 80–100% DoD without accelerated degradation.
NMC (Nickel Manganese Cobalt) — older units, avoid for backup
- Cycle life: ~500 cycles to 80% — at 20 cycles/year, that's ~25 years on paper but degradation is non-linear. Most NMC units noticeably lose capacity at 3–5 years with regular use.
- Higher energy density — lighter per Wh, which matters for camping, less so for home backup where weight is irrelevant.
- Older Jackery models (pre-2000 Plus), older EcoFlow River series.
Every unit in this roundup uses LFP. If you're looking at older or budget units, verify the chemistry. "Lithium" alone is not enough — NMC is also lithium. Look specifically for "LiFePO₄" or "LFP" in the spec sheet.
FAQ
Can I run my whole house on one of these?
Partial-home, yes. Whole-home (HVAC, electric water heater, electric dryer, EV charger) — no, unless you're scaling to 20kWh+ with a Delta Pro Ultra or Bluetti AC500 system. The realistic approach is a "critical circuit" strategy: keep your fridge, router, lights, phone charging, CPAP, and maybe a window AC running. That's a 500–800W continuous load, manageable for 24 hours on a 2kWh unit with solar recharging.
Do I need a transfer switch?
For most portable setups, no. You plug directly into the power station. If you want the unit to supply your home's circuits during an outage, you need a transfer switch — and that requires an electrician. EcoFlow and Bluetti both sell home integration kits for this. For preparedness-level use without electrical work, a simple extension cord and power strip handles most needs.
How much solar do I need to sustain indefinitely?
Match your daily Wh consumption with solar production, accounting for ~70% efficiency and cloud days. If your basic outage load is 1,900 Wh/day, you need ~2,700 Wh/day of nameplate solar in optimal conditions. That's roughly 2–3 × 400W panels. Use our Sizing Calculator to get your exact number.
What's the shelf life if I store it unused?
LFP units should be stored at 50–60% charge in a cool, dry location. Most manufacturers recommend a check charge every 3–6 months. At storage temperatures under 77°F (25°C), LFP holds charge with less than 3% monthly self-discharge. You won't need to worry about it degrading between storm seasons.