The Westinghouse WGen20000TFc is the better portable generator overall, rated 3.9 to 3.7. The Westinghouse WGen20000TFc leads on value. The DuroMax XP15000HXT+ wins on warranty and run time. The DuroMax XP15000HXT+ costs $400 less ($3,499 vs $3,899).
A huge tri-fuel generator that can back up a large home in full, wired in by an electrician or through two 50 A outlets. For buyers who want standby-generator output without a permanent install.
Amazon $3,899A large fuel-injected tri-fuel generator for whole-house backup through a 50 A transfer switch, and one of the few this size that California buyers can get.
Amazon $3,499Prices were last checked October 28, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Each factor is scored 0-100 against the same fixed reference points for every large portable generator; a clear win is highlighted. How we rank explains each one.
| Factor weight | Westinghouse WGen20000TFc | DuroMax XP15000HXT+ |
|---|---|---|
| Overall rating | 3.9/5 | 3.7/5 |
| Value 30% | 32 $0.19 per running watt | 0 $0.29 per running watt |
| Run time 15% | 40 8 hours on a tank at 50% load | 60 10 hours on a tank at 50% load |
| Fuel options 15% | 100 gasoline, propane or natural gas | 100 gasoline, propane or natural gas |
| Home hookup 15% | 100 240 V outlet for a transfer switch | 100 240 V outlet for a transfer switch |
| CO safety 10% | 100 shuts off when carbon monoxide builds up | 100 shuts off when carbon monoxide builds up |
| Warranty 10% | 67 3-year warranty | 100 5-year warranty |
| Starting 5% | 100 electric start with a remote fob or app | 100 electric start with a remote fob or app |
| Westinghouse WGen20000TFc | DuroMax XP15000HXT+ | |
|---|---|---|
| Output | ||
| Gasoline | 20,000 W running, 28,000 W starting | 12,000 W running, 15,000 W starting |
| Propane | 18,000 W running, 25,200 W starting | 11,400 W running, 14,250 W starting |
| Natural gas | 16,000 W running, 22,400 W starting | 10,500 W running, 13,000 W starting |
| Outlets | 4 × 120 V, L5-30, L14-30, 14-50 | 4 × 120 V, 14-50 |
| Transfer switch ready | Yes, 240 V | Yes, 240 V |
| Full power at 120 V | No | - |
| Total harmonic distortion | under 5% | under 5% |
| Price per watt | $0.19 | $0.29 |
| Fuel and run time | ||
| Fuel | Gasoline, propane, natural gas | Gasoline, propane, natural gas |
| Tank | 17.2 gal | 8.3 gal |
| Run time (gasoline) | 8 hr at 50% load | 10 hr at 50% load |
| Engine | 999 cc | 500 cc |
| Noise and safety | ||
| Rated noise | 74 dBA | 74 dBA |
| CO shutoff | Yes | Yes |
| CARB compliant | No | Yes |
| Build | ||
| Starting | Remote, electric and recoil | Remote, electric and recoil |
| Wheels | Yes | Yes |
| Dimensions | 38 x 35 x 40.4 in | 29.5 x 28 x 26 in |
| Weight | 557 lb | 237 lb |
| Warranty | 3 years | 5 years |
| Released | 2024-06 | 2025-06 |
