Systems and methods for zero nox emissions during an operating period

A system, comprising:

• an aftertreatment system including a catalyst;
• an electric motor coupled to an engine;
• a heater positioned downstream of the engine;
• and
• a controller coupled to at least the aftertreatment system, the electric motor, the engine, and the heater, wherein during a warmup period for the aftertreatment system, the controller is configured to:
• initiate the heater to increase a temperature in the aftertreatment system;
• and
• control the electric motor to cause the engine to spin to generate an airflow directed from an intake of the engine to the heater without combustion.

A method, comprising:

• maintaining, by a controller coupled to at least an aftertreatment system, at least an engine in an off state during a warmup period for a system;
• initiating, by the controller, a heater of the system to increase a temperature of the system;
• and
• controlling, by the controller, an air mover of the system to direct airflow from an intake of the engine to the heater to increase the temperature of the system.