A renewable energy generator imposes costs on a power grid from rapid fluctuations in output. A device is disclosed that collects data on renewable power production, meteorological and other information, forecasts short timescale renewable power production then mitigates costs incurred by power fluctuations by modulating the power output, while maximizing power production revenue. Mitigation may be effected by an AC/DC inverter, an energy storage system, demand response or a FACTS device. The magnitude and costs for modulating response required from energy storage, FACTS or other power modulation equipment is thereby reduced.