Researchers at the University of Waterloo have developed a nanotechnology-based leak sensor that reportedly could be produced for $5 each, about a tenth of the cost of current leak detection devices on the market.
By using nanotechnology, the tiny sensor eliminates a battery and related circuitry, allowing it to be made smaller and at lower cost than existing leak sensors. A paper on the research, “Development of novel water leak detection mesh network utilizing battery-less sensing nodes,” was presented at a recent international conference on smart cities and the Internet of Things.
“One of the big issues related to water damage in buildings is that owners don’t install enough sensors because they are too expensive,” said George Shaker, an engineering professor at Waterloo, in an article on the university’s website. “The much lower cost of our sensor enables the deployment of many, many more to greatly improve protection.”
The new sensor, which is smaller than a nickel at 5 mm in diameter, comprises 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 device sends an alert to smartphones when exposed to moisture. The wireless radio and other sensors are on a circuit board packaged with the leak sensor in a box just 3 cm square.
“We harvest the energy that is created when the sensor is exposed to water and that energy then powers the electronics to send an alert to the user’s cellphone via the internet,” said collaborator Norman Zhou, a professor of mechanical and mechatronics engineering.
Asides from low cost, the sensors are 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.
Researchers are also pursuing additional applications for the underlying technology, including in diapers for the elderly and in bandages to detect wound leakage after surgery.