Potential applications envisaged include cogeneration, trigeneration, prime/continuous power, and peaking power, with a wide range of target markets: commercial and institutional (eg, airports, hospitals); utility and IPP (eg, grid firming, waste treatment facilities); and industrial (eg, mining, manufacturing, greenhouses, oil & gas).

“Behind the meter” is seen one area attracting increasing interest and where the new offering should prove attractive. Since September 2019, the Cummins site in Ramsgate, UK, has been using a natural gas fuelled C25G – located in one of the facility’s test cells – to demonstrate the considerable economic benefits of going off-grid. The C25G has been supplying all the facility’s power needs (an average load of about 300 kW), with the surplus capacity (around 200 kW) available to the grid. The in house generated power costs about one-third less than the average 11 p/kWh or so that would be typically paid by an industrial user in the UK for grid supplied power, resulting in savings of about £14000-16000 per month for the Cummins Ramsgate site.

Among key features of the new genset:

  • High power density. 500 kW (50 Hz, 1500 rpm) and 580 kW (60 Hz, 1800 rpm) from a 25 litre V12 engine. The engine is a Liebherr G9512 machine, with a single ABB turbocharger, 13.3:1 compression ratio. Cummins opted for this engine rather developing one of its own to minimise time to market for the new genset offering.
  • High efficiency. Electrical efficiency up to 41.6% (50 Hz) and 40.6% (60 Hz) on pipeline natural gas down to 75 methane number (MN).
  • Fuel flexibility. Can run on biogas down to 18 MJ/Nm3 (450 Btu/scf) at full power and down to 14 MJ/Nm3 (360 Btu/scf) with 70% derate. Capable of running on contaminated low-Btu gases. Pipeline gas natural gas: minimum 75 MN for full power, down to 60 MN with derate.
  • Low emissions. As low as 250 mg/Nm3 (0.5g/hp-hr) NOx without after treatment (compliant with MCPD).
  • Good performance at high ambient temperatures. 50 Hz version can achieve full power (500 kW) up to 41°C ambient (52°C with derate). For 60 Hz version, full power (580 kW) available up to 34°C (49°C with derate).
  • Good performance at high altitudes. 50 Hz machines deliver full power up to 1500 m (max altitude 2000 m, with minor derate). 60 Hz version capable of full power up to 1300 m (max 2000 m, with minor derate).
  • Ease of serviceability. 2000 h minimum interval; 32 000 h mid-life overhaul; 64 000 h full overhaul.
  • Certification/grid code compliance. Meets CE, UL, CSA, ENTSO-e grid codes (eg, RfG, VDE, G99) and EAC (Russian Customs Union) requirements.
  • Good load handling, including 100% load rejection without shutdown and island mode capability.
  • Closed crank ventilation. Reintroduction of filtered crankcase fumes into the engine air intake.
  • Black start capability. Genset can be started and run without auxiliary power.