TR35: Shwetak Patel
From: Technology Review - September/October 2009 - page 66
By: Kate Greene

Simple sensors to detect residents' activities

Walls can talk, and Shwetak Patel, an assistant professor of computer science
and electrical engineering, captures their stories: tales of how people move
through their homes and how they use electricity, gas, and water. Patel has
shown that each electrical appliance in a house produces a signature in the
building's wiring; plugged into any outlet, a single sensor that picks up
electrical variations in the power lines can detect the signal made by every
device as it's turned on or off. This monitoring ability could be
particularly useful for elder care, but there was previously no practical way
to achieve it, because it would have required numerous expensive sensors.  

Last year, Patel did something similar with ventilation systems, designing a
sensor that detects subtle changes in air pressure when a person leaves or
enters a room. More recently, he's shown that slight pressure changes in gas
lines and water pipes betray the use of specific appliances or fixtures, such
as a stove or faucet. Patel believes that providing people with information
about their patterns of resource consumption can help them reduce it. He has
cofounded a startup that will provide consumers with utility bills itemized
by appliance. 

Source:
http://www.technologyreview.com/tr35/Profile.aspx?TRID=814

Link:
Shwetak Patel
http://abstract.cs.washington.edu/~shwetak/