Various systems and methods for an engine system which includes a throttle turbine generator having a turbine which drives an auxiliary generator and disposed in a throttle bypass are described. In some examples, a throttle bypass valve is controlled to adjust airflow through the throttle bypass responsive to airflow to cylinders of the engine. In other examples, an operating parameter such as throttle position is controlled based on transient operating conditions of the engine. In still other examples, charging of a battery is coordinated between the auxiliary generator and a primary generator.