US Patent 7783903 Limiting power consumption by controlling airflow

A power management scheme is disclosed wherein power limits are imposed on devices of an electronic system using selective airflow reduction. In one embodiment, each server in a rack system includes a throttling system for maximizing processor throughput within a fixed temperature constraint. An airflow system is capable of providing a variable amount of airflow to each server. The power consumption for each server is detected by an external power meter circuit and monitored by a controller operatively connected to the airflow source. The controller selectively reduces the amount of airflow to each server in relation to its power consumption, to induce an amount of throttling of each server sufficient to impose its respective power limit.