Overview#
The MTU 6R0135 GS150 is a 150 kW (natural gas) standby generator set powered by a Doosan 8.1L CAC — an 8.1-liter, 6-cylinder inline turbocharged and charge-air-cooled spark-ignition engine producing up to 177 kWm gross on natural gas. On liquid propane, the unit is rated at 100 kW standby, reflecting the lower energy density of LP versus natural gas at the same fuel flow rate.
The engine carries EPA certification with a 3-way catalyst and uses a Bosch electronic isochronous governor (±0.5% speed regulation). Standard equipment includes a 24V electric start system (requiring 1,050 CCA batteries), a unit-mounted radiator rated for 50°C ambient, and the MTU digital control panel with SAE J1939 communications, NFPA 110 compatibility, and IP 54 front panel protection. Dual-fuel operation (NG and LP vapor) is available as a factory option.
The 6R0135 GS150 is a notably larger unit than the diesel R-series at 150 kW — the gas engine platform requires a longer enclosure to accommodate the 8.1L engine block, resulting in a footprint of 142 x 63 inches. Plan for this during site design.
Technical Specifications#
Power Ratings (60 Hz, 1800 rpm)
| Rating | kW | kVA |
|---|---|---|
| Standby — NG | 150 | 187 |
| Prime — NG | 130 | — |
| Standby — LP | 100 | 125 |
Engine — Doosan 8.1L CAC
| Parameter | Value |
|---|---|
| Displacement | 8.1 L (492 in³) |
| Configuration | 6-cylinder inline |
| Aspiration | Turbocharged and charge-air-cooled |
| Rated speed | 1800 rpm |
| Governor | Bosch electronic isochronous, ±0.5% |
| Max gross power (NG) | 177 kWm (237 bhp) |
| Max gross power (LP) | 122 kWm (164 bhp) |
| Emissions | EPA certified, 3-way catalyst |
| Starting | 24V electric, 1,050 CCA |
Fuel Consumption (natural gas at 1000 BTU/ft³)
| Load | NG Consumption | LP Consumption |
|---|---|---|
| 100% load | 1,539 ft³/hr (43.6 m³/hr) | 517 ft³/hr |
| 75% load | 1,191 ft³/hr (33.7 m³/hr) | 390 ft³/hr |
| 50% load | 845 ft³/hr (23.9 m³/hr) | 283 ft³/hr |
Physical (Open Power Unit)
| Dimension | Value |
|---|---|
| Length | 3,607 mm (142 in) |
| Width | 1,591 mm (62.63 in) |
| Height | 1,788 mm (70.38 in) |
| Dry weight | 2,562 kg (5,647 lb) |
Cooling System
| Parameter | Value |
|---|---|
| Radiator ambient rating | 50°C (122°F) |
| Water pump capacity | 240 L/min (63 gpm) |
| Heat rejection to coolant | 164.4 kW |
Our Service Experience#
The Doosan 8.1L CAC platform is a well-established industrial spark-ignition engine with a track record in power generation. The charge-air-cooled configuration improves thermal efficiency and detonation resistance but adds the charge air cooler as a service component to monitor. On natural gas units, the 3-way catalyst is the primary emissions management component — catalyst efficiency should be verified during annual service using exhaust gas analysis.
The 24V start system (versus 12V in the smaller R-series) requires specific battery attention: 1,050 CCA batteries are specified, and both batteries in the dual-battery configuration must be tested at each service interval. A single weak battery in a 24V series configuration can prevent starting.
Gas supply pressure is critical on these units — the 8.1L engine requires a consistent 7–11 inch water column pressure at the inlet. Pressure below this range during a cold-weather start can cause start failures or rough running.
Frequently Asked Questions#
What is the LP power rating versus NG? On natural gas, the GS150 is rated 150 kW standby. On liquid propane vapor, the rating drops to 100 kW standby (100 kVA). This 33% derating reflects the lower energy density and different combustion characteristics of LP at this displacement. Size the unit based on your primary fuel type.
What fuel inlet pressure is required? Both NG and LP vapor supply: 178–279 mm H₂O (7–11 inches of water column). This is a low-pressure specification — most commercial gas services provide adequate pressure, but verify at the generator connection, not at the meter.
Is SCAQMD certification available on the GS150? Unlike the diesel R-series units, SCAQMD certification is not listed for the GS150. The unit carries EPA certification with 3-way catalyst. Consult your MTU Onsite Energy distributor for current air quality district compliance options.
What is the footprint compared to the diesel DS150? The GS150 is significantly larger: 142 x 63 inches versus 112 x 48 inches for the diesel DS150. Gas engine standby units are typically larger than their diesel equivalents at the same power level due to engine block size.
