1
Voltage Gate
PASSDevice output type must match generator output.
120V required -> 120V available
No — the RIVER 2 Max is underpowered for a Sump Pump
Not a safe match. The generator's output falls below the Sump Pump (1/2 HP)'s requirement.
- • Continuous power shortfall: needs 1127W (safe target ~1297W), generator provides 500W.
- • Startup surge shortfall: needs 3381W (safe target ~3889W), generator provides 1000W.
Power Margin Analysis
500W / 1000W Capacity Running 797W short
1297W required
Surge 2889W short
3889W required
Decision Gate Waterfall
Same decision gates as the engine: voltage, running, surge. Runtime is shown as operational context.
2
Running Gate
FAILContinuous draw with safety buffer applied.
1,297W required -> 500W available (797W short)
Required 1,297W required
Available 500W
3
Surge Gate
FAILStartup peak with safety buffer applied.
3,889W required -> 1,000W available (2,889W short)
Required 3,889W required
Available 1,000W
3b
With Soft-Start
FAILAlternative startup path with reduced inrush.
1,750W required -> 1,000W available (750W short)
Required 1,750W
Available 1,000W
4
Runtime Insight
INFORuntime context only. It does not change the electrical compatibility verdict.
Runtime estimate appears after running and surge gates pass.
Power bars show required versus available output for each gate.
See generators that pass nativelyDecision Snapshot
Quick compatibility, required headroom, and model-specific context at a glance.
⚡
500W
Running Power
🔋
512Wh
Capacity
⏱️
—
Est. Runtime
☀️
220W
Solar Input
Quick Compatibility Check
- 1 Running headroom: target 1297W; generator provides 500W.
- 2 Surge headroom: target 3889W; generator provides 1000W.
- 3 Result: pick a higher-output unit for safe operation.
What To Do Instead
- 1 Underpowered: The Sump Pump (1/2 HP) needs 1297W running / 3889W surge (with 15% buffer). The RIVER 2 Max provides 500W / 1000W.
- 2 Safe target: Look for a power station with at least 1297W continuous and 3889W surge at 120V.
- 3 Compatible alternative: The Explorer 2000 Plus (3000W / 6000W surge) clears this device's requirements.
Model-Specific Results
0 of 3 models are SAFE or TIGHT. Most demanding model: Wayne CDU800 (1/2 HP) (3,381W surge).
| Model | Running | Surge | Verdict | Runtime | Source |
|---|---|---|---|---|---|
| Zoeller M98 Flow-Mate (1/2 HP) | 1,081W | 3,243W | Fail | — | NEC Standard |
Show expert analysisTechnical: **Running load:** 1,081W (115V x 9.4A OEM rated). **Surge:** 3,243W at motor startup (3x NEC estimate). **Voltage:** 120V AC. The cast iron PSC motor draws heavy inrush current on every pump cycle. Field note: The Zoeller M98 is the industry reference in cast iron sump pumps. Its PSC motor has no built-in soft-start — the full inrush hits the power station instantly. An external soft-start device can reduce this surge, but size the inverter for the full 3,243W if running without one. Can I run a Zoeller M98 sump pump on a portable power station during a flood? Only if your power source can supply at least 1,081W continuous and 3,243W surge at 120V. The PSC motor creates a hard startup spike that will trip undersized inverters. | |||||
| Wayne CDU800 (1/2 HP) | 1,127W | 3,381W | Fail | — | NEC Standard |
Show expert analysisTechnical: **Running load:** 1,127W (NEC 430.248 rated). **Surge:** 3,381W at motor startup (3x NEC estimate). **Voltage:** 120V AC. The coated steel PSC motor draws the highest inrush in this class due to its conservative NEC-rated amperage. Field note: The Wayne CDU800 is the Home Depot best-seller for suburban basements. Without OEM amperage data, specs are derived from NEC tables — the actual draw may be slightly lower, but sizing to NEC ensures safe headroom. Can I keep my Wayne sump pump running on battery backup during a storm? Only if your power source can supply at least 1,127W continuous and 3,381W surge at 120V. The motor startup surge is the critical factor — most small power stations cannot handle it. | |||||
| Liberty Pumps 287 VMF (1/2 HP) | 920W | 2,645W | Fail | — | OEM Manual |
Show expert analysisTechnical: **Running load:** 920W (115V x 8.0A OEM rated). **Surge:** 2,645W at motor startup (115V x 23A LRA, OEM verified). **Voltage:** 120V AC. The 3450 RPM PSC motor with OEM-documented LRA provides the most precise surge data in this class. Field note: The Liberty 287 is the plumber's choice and the most battery-friendly 1/2 HP sump pump in this comparison. With OEM-verified LRA data, the 2,645W surge is a confirmed number — not an estimate. A 3,000W power station can handle this reliably. Is the Liberty 287 easier to run on a power station than other sump pumps? Only if your power source can supply at least 920W continuous and 2,645W surge at 120V. Its OEM-documented 23A locked rotor current is lower than NEC estimates for competing 1/2 HP pumps, making it more generator-friendly. | |||||
How This Pairing Performs Across Our Database
This unit is outside the compatible set; 17 of 33 generators pass SAFE/TIGHT for this device.
How Sump Pump (1/2 HP) Performs Across 33 Tested Generators
17 of 33 generators are SAFE+TIGHT for Sump Pump (1/2 HP).
17
Safe+Tight
Safe 12 (36%)
Tight 5 (15%)
Soft Start 6 (18%)
Fail 10 (30%)
Power Comparison: EcoFlow RIVER 2 Max vs Top Alternatives for Sump Pump (1/2 HP)
EcoFlow RIVER 2 Max Fail
Current unit
Running 500W
Surge 1,000W
Fit class uses buffered needs (running and surge) for this device.
Specs & Surge Analysis
Emergency
Sump Pump (1/2 HP)
Storm Flood Prevention
Select Your Model:
1127W
Running
3381W
Surge
120V
Required
True Surge™ Analysis
Safety Buffer: +15% Running Power Usage 259% Utilization
1297W required 500W Capacity
797W short
Surge/Startup Peak 389% Utilization
3889W required 1000W Capacity
2889W short
Voltage Match 120V ↔ 120V ✓
Startup Surge Visual
Startup Surge
Sump Pump (1/2 HP) vs RIVER 2 Max
Startup surge exceeds the power station limit. A soft starter may resolve the surge gap.
⚠️
Before You Buy: Connection Check
Installation warning
These systems are often hardwired to a home panel. To run them from a portable station, you may need a transfer switch installed by an electrician. You cannot just plug it in.
Compatible Alternatives to RIVER 2 Max
These generators meet Sump Pump (1/2 HP)'s voltage, running, and surge requirements.
Best Value 
Explorer 2000 Plus
3000W • 2042Wh
Runtime at your load
~1.3h
Capacity Fit Expandable to 12000Wh
Lowest capacity that still clears surge + running load.
Max Runtime 
Delta Pro
3600W • 3600Wh
Runtime at your load
~2.2h
Longest Runtime Expandable to 25000Wh
Expandable to 25000Wh.
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Generator Insights
The 1000W surge can handle typical compressor startup events in refrigerators, window AC units, and well pumps that fall within momentary draw limits. Sustained loads must stay at or below 500W to avoid shutdown. This is a light-duty unit for essential circuits, not whole-home backup.
This portable station uses LFP chemistry, known for thermal stability in consumer lithium batteries. The 512Wh capacity and 500W continuous rating provide a workable buffer for appliances within spec. Source: EcoFlow RIVER 2 Max User Manual v1.0 (manufacturer documentation).
Technical Analysis
Spec-Based • No GuaranteesTechnical Breakdown
Running load: 920–1,127W depending on model. Surge: 2,645–3,381W at motor startup. Voltage: 120V AC required. All 1/2 HP sump pumps use PSC induction motors with significant startup inrush — the surge is the critical sizing factor for battery backup.
Expected Behavior
Sump pumps activate automatically via float switch during flooding. Each motor start produces a surge lasting 1-3 seconds. Typical storm usage: 2 hours/day with intermittent cycling. Daily energy: 1,840–2,254 Wh.
Field Note
Sump pump backup is the #1 emergency use case for portable power stations. The motor startup surge — not the running watts — determines whether your power station can handle it. Check the surge rating, not just the wattage.
Frequently Asked Questions
Can the EcoFlow RIVER 2 Max power a Sump Pump?
No. The EcoFlow RIVER 2 Max falls short on both running (500W offered vs 1297W needed) and surge (1000W offered vs 3889W needed). Safe targets include a 15% buffer for the Sump Pump (1/2 HP)'s motor load profile.
How long will the RIVER 2 Max run a Sump Pump?
No reliable runtime estimate — this pairing is not compatible. The EcoFlow RIVER 2 Max cannot safely power the Sump Pump (1/2 HP). See compatible alternatives above for power stations that meet this device's requirements.
Storm Safety: Since the Sump Pump (1/2 HP) is critical for preventing flooding, we recommend testing this setup specifically before the storm season. Ensure the RIVER 2 Max is fully charged to 100% as storms approach.
Compare all 33 generators for the Sump Pump (1/2 HP)
Ranked by budget, runtime, and overall compatibility.
Technical Sourcing & Verification
ID: ecoflow-river-2-max-sump-pump-half-hp 🏛️ Device Data Source
Engineering Est. Safety Factor Applied
Derived from variant list (max of variants). Worst case = Wayne CDU800 (1127W running, 3381W surge).
⚡ Generator Specs Source
OEM Verified
EcoFlow RIVER 2 Max User Manual v1.0
Methodology informed by US Department of Energy (DOE) & EIA references where applicable.
Our methodology →
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