The PSI 21.9L is a 21.9-liter, 12-cylinder v-12 natural gas / lpg engine used in commercial and industrial generator applications in the 375-450 kW class. Turbocharged Intercooled for reliable power density across standby and prime-rated duty cycles.
This engine powers generators from Blue Star Power Systems, Hipower Systems, making it one of the more widely deployed prime movers in its power class for the commercial standby market.
Generator models that ship with or are commonly paired with the PSI 21.9L.
Blue Star Power Systems
Blue Star NG400-01
Open Basler controller + PSI V12 engine + Stamford alternator — no proprietary lock-in. Non-proprietary components serviceable by any qualified tech.
400 kW standby · Natural Gas / LPG · Liquid-cooled
400 kW natural gas standby for large commercial, campus, and data center facilities where gas-fueled backup and component independence matter.
400 kW natural gas / LP standby generator from Blue Star Power Systems. PSI 21.9L turbocharged V12, DSE DCP7310 controller, structural steel base, three-phase 208-600V.
Open Basler controller + PSI V12 engine + Stamford alternator — prime-rated, no proprietary lock-in. Serviceable by any qualified tech.
400 kW standby · Natural Gas / LPG · Liquid-cooled
375 kW prime natural gas for continuous-duty commercial, CHP, and campus applications needing 24/7 gas-fueled power.
375 kW prime-rated natural gas / LP generator from Blue Star Power Systems. PSI 21.9L V12, DSE DCP7310 controller, structural steel base, three-phase 208-600V.
Open Basler controller + PSI V12 engine + Stamford alternator — no proprietary lock-in. Non-proprietary components serviceable by any qualified tech.
425 kW standby · Natural Gas / LPG · Liquid-cooled
425 kW natural gas standby for large commercial, campus, and data center facilities where gas-fueled backup and component independence matter.
425 kW natural gas / LP standby generator from Blue Star Power Systems. PSI 21.9L V12 turbocharged-aftercooled, DSE DCP7310 controller, three-phase 208-600V.
Open Basler controller + PSI V12 engine + Stamford alternator — no proprietary lock-in. Non-proprietary components serviceable by any qualified tech.
450 kW standby · Natural Gas / LPG · Liquid-cooled
450 kW natural gas standby for large commercial, campus, and data center facilities where gas-fueled backup and component independence matter.
450 kW natural gas / LP standby generator from Blue Star Power Systems. PSI 21.9L V12 turbocharged-aftercooled, DSE DCP7310 controller, three-phase 208-600V.
CARB-certified large stationary natural gas standby from Hipower's HNG series — utility-supplied fuel, no on-site diesel storage, broad voltage options.
400 kW standby · Natural Gas / LPG · Liquid-cooled
California industrial and large commercial buildings at 400 kW with natural gas service where CARB certification is required.
400 kW stationary natural gas generator with PSI natural gas engine. CARB certified for California standby. Largest model in Hipower's HNG series.
