Systems and methods for dynamically charging energy storage devices connected to a power grid or other power system are provided. Charging decisions for charging the energy storage devices may be optimized, for example by basing the decisions on historical data, to provide more efficient or effective charging and use of power. The historical data may include an amount of energy previously discharged by each of the energy storage devices, a previous charging decision for each of the devices, a previous total fixed load power request of the power grid, and/or a pervious amount of power received by the power grid, which may include power received from intermittent power sources. In some aspects, the present techniques do not require current system state information or explicit predictions of future intermittent power availability. In some aspects, charging decisions are based on a solution to an online optimization problem.