Siemens Energy selected to supply hybrid drive for Massachusetts LNG facility

Published on October 25, 2022 by Dave Kovaleski

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Siemens Energy was tapped by Northeast Energy Center (NEC) to supply a gas/electric hybrid drive system for a new LNG plant being built in Charlton, Mass.

This groundbreaking project will be the first LNG facility in the world to feature a system of this type, which is designed for greater efficiency no matter the weather or temperature. Siemens will serve as the supplier of the integrated drive, providing all rotating equipment and associated control systems.

The hybrid drive system will combine a Siemens Energy low-emissions industrial gas turbine, integrally geared compressor, and electric motor-generator to ensure efficient operation of the plant’s main refrigeration/liquefaction train throughout the year. It will slash emissions, reduce costs, and increase efficiency.

It is different because available power from gas turbines decreases as the ambient temperature increases. Thus, units installed at industrial facilities are typically oversized to ensure sufficient power during the hot and humid weather. However, the same gas turbine may generate much more power when cold than is required, which is less efficient and increases emissions.

This hybrid drive refrigeration compressor system provides a solution to that problem as it combines an electric motor-generator with a gas turbine that features a dry-low emissions (DLE) design with the lowest achievable NOx emissions levels. It gives NEC a powerful tool in demand-side management and reduces its costs and the need to purchase power from the grid.

The NEC project is expected to produce a baseload of 170,000 gallons of LNG per day for Boston Gas under a firm contract and up to 250,000 gallons per day to other utilities. The gas turbine’s output will decrease when LNG production increases to 250,000 gallons per day on hot summer days when the motor-generator will function as a motor to supply additional power to the compression system.

“The reality is when it comes to facilitating the energy transition, natural gas can be a solution,” Rich Voorberg, president of Siemens Energy North America, said. “It will serve as a reliable complement to renewable energy in many regions of the world. The combination of the gas turbine, integrally geared compressor, and motor generator at the NEC plant represents a highly flexible solution that will enable the liquefaction plant to operate efficiently year-round, regardless of the ambient conditions. This will significantly reduce overall energy consumption over the plant’s life, resulting in a lower carbon footprint.”

The plant has an onsite LNG storage capacity of 2 million gallons.

“The integrated hybrid drive solution provided by Siemens Energy demonstrates the next step in hybridization of the energy systems in their decarbonization process,” Boris Brevnov, manager and developer of NEC, said. “Building on this next-generation design and its environmental advantages, NEC also offers local utilities a choice of L-RNG, an LNG product made from renewable natural gas.”