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Residential Plug-in
Devices Study

Understanding the energy used by the plug-in devices we use at home everyday.

Study Introduction

An online screening survey is available to all EETD staff who wish to be considered for the residential plug-in devices study. Project staff will select two households and notify survey respondents within two weeks after the selection process has been completed. Unselected surveys will be destroyed at the end of the study.

To be considered, the following requirements must be met:

  1. Homeowners must be at least 18 years old;
  2. Homeowners must live in their own single-family home that is within ten miles of LBNL;
  3. Homeowners will be residing in their home for the six month study period and only away for periods of up to seven days at a time.

For the selected households, the study consists of the following steps:

Total time commitment for the homeowner is expected to be around 20 hours, including the initial setup, final visit, and any checkup on metering equipment as needed during the study.

Home Visit: interview and guided walk-through

Project staff will visit the home and interview the homeowner, perform a plug-in device inventory, and install approximately 50-75 plug-load meters, a wirelss router, and a whole house meter.

During the interview, the researchers and homeowner will cover the following items:

  1. Review of study consent and protocol
  2. Briefly interview homeowner about the locations and usage patterns of plug-in devices in the home, location of main electrical meter and panel, and information about hardwired or inaccessible devices
  3. Develop a plan for the inventory and meter installation with the homeowner
  4. Show homeowner the metering devices and explain how they work
  5. Review homeowner instructions, including contact information if issues arise and meter log to be filled out by homeowners for transient devices
  6. Address any questions and concerns

Following the interview, researchers will perform a preliminary walk-through with homeowner to identify locations/rooms and location of plug-in devices.

Home Visit: inventories and meter installations

After the preliminary walk-through, researchers will perform plug-in device inventory and meter installations around the home. Depending on the number of plug-in devices in the home, 50-75 meters will be installed along with a wireless router by the researchers. A licensed electrician will be hired to install a whole-house electricity meter on the same day.

(Note that the plug-in electricity meters are similar to AC adapters, each plug-in device will be plugged into a meter, which in turn, is plugged into the household outlet. They wirelessly transmit the energy use data the router. The wireless router will collect the energy use data and send the information to a central server. The whole-house electricity meter will measure the real-time energy use of the household.)

Inventory methods may include video/audio recording, and device information such as product description, model number, and power consumption rating will be recorded. Any video images containing people or personal identification information will be immediately deleted, and all videos will be erased at the conclusion of the project. A sketch of the rooms, depicting the locations of plug-in devices and electrical outlets, will be drawn to facilitate device identification and data processing.

Here are some possible configurations of meters and devices:

Plug-in devices plugged into ACme meters
(black boxes), then into wall directly or
into outlet rotator and then wall. 
Plug-in device plugged into ACme meter
(black box), then surge protector, then

Logging of Transient Plug-in Devices

Transient plug-in devices are those that are sporadically used or mobile. We will make an effort to ensure all commonly used devices are plugged into plug-load meters during the initial setup. We will also install plug-load meters on outlets that are unplugged during the initial setup but indicated to be frequently used. Extra plug-load meters will be left for the homeowner for recording transient devices.

To help us get the best possible data:

  1. Always plug devices into the outlet through one of the plug-load meters provided.
  2. For devices (currently plugged into a plug-load meter) that are moved to a different outlet after the initial setup, we ask that the homeowner make a note of the new outlet location and corresponding meter ID number.
  3. For transient or new devices that are plugged in after the initial setup, we ask the homeowner to record the device type, model number, meter number, and date and time of installation.

Our goal is to measure the energy use of every device being used in the study home, and we need to know what device is plugged into which meter at what time to get the most out of the data we collect. In addition, residents are encouraged to continue with their regular usage pattern of plug-in devices during the 6-month study period.

Uninstall of Meters

At the end of the study, researchers will schedule a 4-hour visit to remove metering equipment and conduct a follow-up interview. Homeowners will have the option of keeping the whole house electricity meter (instructions will be provided).

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We would like to meter plug-in devices in the selected homes for 6 months from July 2010 through January 2011. Initial home visit is expected to be in early to mid July for inventory and meter setup.

Human Subjects Information

The Human Subjects Committee (HSC) has reviewed and approved this research. The HSC is the Institutional Review Board (IRB) for LBNL. LBNL holds Office of Human Research Protections Federalwide Assurance number FWA 00006253.

Approval number: 286H01-24JUN11
Approval date: June 24, 2010
Expiration date: June 24, 2011

If you have any questions regarding your rights or treatment as a volunteer in this research study, contact the Lawrence Berkeley National Laboratory's Human Subjects Committee at 510-486-5539 or