Briggs & Stratton PowerProtect+ 18kW
#7 in 15 to 22 kWFull review
For average homes on natural gas that want full rated output and a long warranty with service included.
Norwall $6,899$6,899
The Briggs & Stratton PowerProtect+ 18kW rates 3.2 among 15 to 22 kw standby generators; the Briggs & Stratton PowerProtect 13kW rates 3.1 among under 15 kw ones. The Briggs & Stratton PowerProtect 13kW costs $2,439 less ($4,460 vs $6,899).
Briggs & Stratton PowerProtect 13kW
#7 in Under 15 kWFull review
For buyers covering essentials who already have, or will buy, a separate transfer switch and want a long warranty.
Norwall $4,460$4,460
Prices were last checked November 1, 2026 and are subject to change; the price and availability shown by the retailer at the time of purchase apply.
Scores side by side
These two sit in different size classes (15 to 22 kw and under 15 kw), and each is scored against the reference points for its own class, so a rating says how well each does among its own size peers. How we rank explains each factor.
| Factor weight | Briggs & Stratton PowerProtect+ 18kW | Briggs & Stratton PowerProtect 13kW |
|---|---|---|
| Overall rating | 3.2/5 | 3.1/5 |
| Value 35% | 7 $383 per kW ($6,899 with transfer switch, 18 kW on propane) | 54 $343 per kW ($4,460, 13 kW on propane) |
| Transfer switch 15% | 100 includes a 200 A transfer switch | 0 transfer switch bought separately |
| Noise 15% | 50 66 dBA rated in normal operation | 25 69 dBA rated in normal operation |
| Power quality 10% | 83 under 5% THD | 83 under 5% THD |
| Warranty 25% | 57 7-year warranty | 57 7-year warranty |
Specifications
| Briggs & Stratton PowerProtect+ 18kW | Briggs & Stratton PowerProtect 13kW | |
|---|---|---|
| Output | ||
| Rated output, propane | 18 kW | 13 kW |
| Rated output, natural gas | 18 kW | 11.5 kW |
| THD | Under 5% | Under 5% |
| Engine | 993 cc | 627 cc |
| Engine speed | 3,600 rpm | 3,600 rpm |
| Install | ||
| Transfer switch | Included, 200 A | Sold separately |
| Load management | No | No |
| Remote monitoring | Yes | - |
| Enclosure | Aluminum | Aluminum |
| Dimensions | 46 x 27 x 28 in | 28.5 x 25.5 x 37.6 in |
| Weight | 490 lb | 315 lb |
| Noise and warranty | ||
| Noise, normal operation | 66 dBA | 69 dBA |
| Noise, weekly self-test | 62 dBA | 65 dBA |
| Warranty | 7 years | 7 years |
| Released | 2026-05 | - |