An integrated circuit comprising a plurality of functional blocks, each functional block being operative to cause one or more power consuming events, each power consuming event being associated with a respective weight. The integrated circuit also comprises at least one accumulation block for monitoring the functional blocks over a time window and generating a weighted count of the number of occurrences of each power consuming event within the time window; and a power calculation module for calculating a runtime power consumption estimate over the time window using the weighted count. The weighted count may comprise a sum of products of each one of the power consuming events by its respective weight. Calculating the runtime power consumption estimate may comprise averaging the weighted count over the time window to generate a dynamic power estimate, calculating a leakage power estimate over the time window, and summing the dynamic power estimate with the leakage power estimate. The integrated circuit may further comprise a power management module for adapting power consumption of the integrated circuit based on a comparison of the runtime power consumption estimate with one or more predetermined thresholds.