EECD: A Code Dissemination protocol in a WSN-based Home Energy Management System A WSN enabled Home Energy Management System (HEMS) can achieve user behaviour change by providing real-time feedback of domestic energy consumption. However, features in collecting nodes within HEMS Systems need to change to allow new working patterns to be established which adapt to ad-hoc demands for energy data retrieval, e.g. different acquisition frequencies, and light-weight quality control of retrieved data. In this paper, a code dissemination protocol, called EECD (Excellence Estimation Code Dissemination) is presented to implement remote reprogramming of WSN nodes, without any manual replacement of them. Compared to Deluge, the default wireless reprogrammingprotocol in the TinyOS, the EECD can obtain a performance improvement of 24% in terms of completion time.