Cummins adds 78L Centum Series gen-sets

Cummins Power Generation continues to expand its Centum Series generator set line, presenting its recently announced 1,750-kW C1750D6E and 2-MW C2000D6E and the all-new 2,750-kW C2750D6E and 3-MW C3000D6EB to customers and distributors during an event held in early April at its Power Systems headquarters in Fridley, Minn., where the Centum Series is produced.

The two newest models, the C2750D6E and C3000D6EB, are engineered specifically for mission-critical applications such as data centers, healthcare facilities and wastewater treatment plants. Designed with a smaller footprint, they allow for space optimization and maximum power output, representing a significant shift in the Cummins approach to power system design, the company noted.

With their smaller footprint, the new models allow for both space optimization and maximum power output. (Photo: Cummins)

“The energy demand for our customers is continuing to grow multiple fold. Hospitals that used to have some 1-MW gen-sets are now buying 2- or 3-MW type units,” said Vipul Tandon, executive director of Cummins Global Power Generation. “What we’re seeing across the board is the energy demand for applications continues to rise, and with that comes the need for reliable, right-sized gen-sets.”

Even as energy demand rises, space constraints at customer facilities continue to be a limiting factor. “Real estate is valuable, and we kept that in mind as we were designing the Centum Series,” said Scott Towsley, director, chief engineer for Cummins Mission Critical Americas. “We tried to minimize that [package size] as much as possible.” The result is a compact, power dense design.

Efficient fuel burn

The C2750D6E and C3000D6EB are powered by the 78L QSK78 heavy-duty, turbocharged and aftercooled industrial diesel engine incorporating Cummins’ modular common rail fuel system (MCRS). According to Towsley, the MCRS works in connection with the electronic control modules to deliver precisely controlled fuel injection at very high pressures. This enables efficient fuel burn as the diesel fuel is injected into the cylinders converting the fuel into power.

The air handling system developed by Cummins Turbo Technologies further optimizes the combustion process. “With improvements in technology and modeling, we were able to improve the efficiency of the turbochargers, which extract thermal energy out of the exhaust stream that would have normally just gone out of the exhaust,” said Towsley.

Optimized cooling pulls heat out of the compressed gas and enables delivery of low-temperature, high-density air back into the cylinder. (Photo: KHL Staff)

Optimized cooling pulls heat out of the compressed gas and enables delivery of low-temperature, high-density air back into the cylinder. “By putting that air in the system at high pressure ratios, [it] allows us to optimize the combustion, again squeezing all that thermal energy out of the diesel fuel and doing it in a way to manage all the emissions constituents, particulate as well as NOx,” Towsley explained.

Much of this efficiency has been achieved through synergies within the Cummins family. “One of the ways we are different at Cummins is our sister BUs [business units] make a lot of the enabling technology,” said Tandon, “so, turbochargers, fuel systems, emission solutions [that] allow us to go into the most demanding applications for our customers.”

One such example is refinements in Stamford’s new S9 alternator series that enable more efficient conversion of mechanical energy into electrical energy, Towsley said.

“Then, wrapping it up, our PowerCommand Module pulls everything together to work in harmony – the engine, the alternator and the controls,” he added.

Sustainable solution

Like Cummins’ other standby generators, all Centum Series models are authorized for use with paraffinic fuels (per EN15940), including HVO fuel, without any engine modifications required.

“Across all of our range – all the way down into the low kW segment – [our gen-sets] are authorized for 100% HVO use as one of the first OEMs in the industry,” said Tandon, “and we expect that to continue to scale. That’s one example of our sustainability commitment that we will continue to leverage.

“We feel a responsibility to be an enabling partner for pivotal industries like data centers that are on the forefront of innovation and sustainability,” he continued. “This has driven our investments in products like the Centum Series that are delivering a step change improvement in how power is delivered for today and future generations.”

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