Patent attributes
A combined engine system is disclosed which may help to meet electrical power demand of a common load that can vary in an unpredictable manner. The system comprises at least one primary engine and one or more secondary engines. An after-treatment system is connected to the engines to receive exhaust flow from each of the engines. A controller is configured to operate the system in a first operating mode when only the primary engine is running and a second operating mode when the secondary engines are run together with the primary engine. Exhaust flows from each of the engines are passed through the after-treatment system which allows the after-treatment system to be heated by the exhaust flow of the primary engine before receiving exhaust flows from the secondary engines.