The AC meters (ACme) used in this study were developed by UC Berkeley as part of the Green Soda Project, and these devices have been updated for use in our study. The ACme devices form a Internet Protocol (IP) based wireless mesh network and report data over the Internet to a database.
We are currently testing a batch of devices to develop complete performance specifications.
- Rated for 15A at 120V
- Accuracy for real power: 1W or 5% (using the larger value)
- Accuracy for apparent power: 3VA or 10% (using the larger value)
- Device dimensions: 5cm x 7.5cm
- Typical dissipation: 0.5W
- Maximum dissipation at 15A: < 2W
- Variable data reporting rate of 1s or longer (currently 15s)
Plug-in device plugged into ACme meter (black box), ready to be plugged into: surge protector, extension cord, or directly into wall.
The meters being used have been approved for electrical safety by EH&S for use at LBNL. EH&S tested the devices in the following ways:
- Ground-bond; 20A for 1 minute
- Leakage current; < 3.5mA in 8 different failure configurations
- Insulation test; 500V, no dielectric breakdown.
Participating homeowners may see their electricity usage increase by approximately $4 a month as a result of the ACmes. However, savings opportunities identified by researchers over the course of the study could result in savings of more than $24 if the homeowner chooses to adopt the researchers' recommendations.
The ACmes are not available for sale, but the design and software are available from UC Berkeley.