Or: the not-so smart part of the smart grid.
Thankful for the Yokohama Green Power project, part of Yokohama Smart City Project, we enjoy use of a 2011 version Home Energy Measurement System (HEMS). The diagram shows the energy management components surrounding the home gateway, the energy measurement unit is a separate unit near the utility breaker box. The HEMS was an option of the solar system we installed and is ours to use at 40% of its device cost subsidized, in return for sharing data over the course of 4 years with its supplier, Toshiba, and ultimately with the City of Yokohama. We have completed our solar year 3 with another fine harvest. According to the feed-in payments we get from TEPCO, the solar system performs 10% better than the forecast by the installer, Nitten Solar. (The HEMS reports even 10% on top of that, but that I discard as measurement uncertainty).
Do the stakeholders get their money's worth?