The tiny device, say the researchers, uses nanotechnology to power itself and to send an alert to smartphones when exposed to moisture. According to the researchers, the sensor could be commercially produced for $1 each - about a tenth of the cost of current leak detection devices on the market.
"One of the big issues related to water damage in buildings is that owners don't install enough sensors because they are too expensive," says George Shaker, an engineering professor at Waterloo. "The much lower cost of our sensor enables the deployment of many, many more to greatly improve protection."
Measuring five millimeters in diameter, the sensor consists of stacked nanoparticles. When the nanoparticles get wet, a chemical reaction produces enough electricity to power a wireless radio and additional sensors to record environmental conditions, such as temperature.
The wireless radio and other sensors are on a circuit board packaged with the leak sensor in a box just three centimeters square.
"We harvest the energy that is created when the sensor is exposed to water," says collaborator Norman Zhou, a professor of mechanical and mechatronics engineering, "and that energy then powers the electronics to send an alert to the user's cellphone via the internet."
In addition to being less expensive, say the researchers, the new sensors are also environmentally friendly, reset after use, can be installed in hard-to-reach places - including otherwise inaccessible areas during building construction - and require much less maintenance. The researchers believe the underlying technology has the potential to solve several important problems and are currently exploring commercialization.
A paper on the research - "Development of novel water leak detection mesh network utilizing batteryless sensing nodes" - was presented at a recent international conference on smart cities and the Internet of Things.