Overview#
The Gillette SP-1500 is a 150-kilowatt natural gas (130 kW LPG) standby generator that fills the mid-range commercial gaseous backup slot — large enough for multi-family buildings, schools, houses of worship, and light-industrial facilities. At this power class, it competes directly with the Kohler KG150 and Generac SG series.
Like all Gillette SP Series units, the SP-1500 uses industry-standard name-brand components: a PSI 8.8-liter turbocharged and charge-air-cooled V8 engine (537 cubic inches), Stamford UCI274G alternator, and Deep Sea Electronics DSE 7420 MKII controller. Every unit is assembled and 100% load-tested at Gillette's factory in Elkhart, Indiana.
The PSI engine platform#
The SP-1500 steps up to PSI's 8.8-liter turbocharged V8 — a 537-cubic-inch industrial gas engine purpose-built for stationary power generation. This is PSI's workhorse platform for the 130-200 kW range, with turbocharging and charge air cooling to extract 259 brake horsepower on natural gas at 1800 RPM.
Key characteristics of the 8.8L TCAC platform:
- Electronic governor with isochronous frequency regulation (1/4% steady-state)
- Turbocharged and charge air cooled for higher power density
- Electronic fuel injection for consistent air/fuel ratio across load range
- Catalytic converter compatible for sites requiring additional emissions control
- 10.1:1 compression ratio optimized for gaseous fuel efficiency
The 8.8L V8 shares component-level commonality with the larger SP-2000P (which uses a high-output variant of the same block), so parts and service knowledge transfer across models.
Our service experience#
The PSI 8.8L is a well-documented industrial engine with straightforward service access. The DSE 7420 MKII controller is the same platform we see across many generator brands — no proprietary software or dealer-locked diagnostics. At 150 kW, parts availability through industrial distributors is solid for PSI and Stamford components. We recommend keeping critical spares on-site since there is no local Gillette dealer in Northern California: spark plugs, oil filters, air filter, and a replacement battery.
