Accurate harvested energy prediction of the energy harvesting Internet-of-things (IoT) nodes is the basis of the proper power management and should be low-overhead.A new multi-algorithm fusion framework,which merges results of multiple prediction algorithms to achieve a higher accuracy,has been proposed.A three-algorithm fusion solar radiation predictor was implemented.The experiments using the real solar radiation data show that it improves the percentage prediction error by 10％-26％ for different prediction intervals.Its complexity is low enough to run on the embedded systems in real-time.