Sensors are one of the fundamental elements of smart buildings. They provide the foundation of data collection that allows all Internet of Things (IoT) applications to function. The falling cost and reduced size of sensors has been a significant market driver.
Now a rapidly maturing type of sensor offers a revolutionary drop in both size and cost, these sensors are printed, organic, thin, flexible, and promise to fundamentally change the buildings landscape once again.
“Sensors are the heart of the IoT — and printed organic sensors can be used in ways that others cannot,” writes Ed Brown, Editor of Sensor Technology. “They are lightweight, flexible, stretchable, and soft, so they can bend, twist, or conform to any surface. They can be laminated onto fabric or provide a soft interaction between a robot and an object. New applications are evolving as these sensors become more sophisticated, reliable and inexpensive.”
The printed electronics sector actually began more than 10 years ago with companies like Germany-based InnovtionLab, which developed a roll-to-roll system to print a wide variety of sensor types using specially designed inks. Their approach allowed design prototypes to be immediately transferred to industrial processes for an inexpensive and high-speed mass-produced scale. While early options only offered simple sensory functionality, the potential was clear, and now the last decade of development has brought the technology to the fore.
“Printed and organic electronics (POE) are based on the combination of new materials and cost-effective, large-area production processes that open up expansive new fields of application,” we wrote in an article back in 2015. “The technology has the potential to be a game-changer across the board, and the imagination runs wild with the profound implications of POE for the future smart buildings industry.”
Through low-cost manufacturing, low-weight, and thin-form factors, these highly flexible sensor systems may soon replace many traditional sensors and spark a whole new range of applications that could fundamentally change the smart building landscape.
These unique attributes of printed sensor technology mean they can be used over large areas such as walls and floors. Touch-sensitive walls would allow building occupants and visitors to literally interact with the wall. Such technology could be implemented to control lighting, for example, to replace traditional light switches and allow a new level of user-focused functionality. The same concept could presumably be applied to sound and environmental control among other things.
Pressure-sensitive floors have long been used by the automotive industry based on sensors that recognize weight on car seats, for example. However, the low production costs of conductive ink-based printed sensor technology will allow such functionality over much wider areas, such as the floors of meeting rooms, lobbies, and other building spaces. Printed sensor floors would offer a highly accurate method for occupancy analytics, for example, allowing building managers to see the location of all people, which is especially significant for social distancing in the pandemic era.
Another innovative and commercially viable application is thin-film moisture sensors, which determine humidity on surfaces. Due to the low-cost of ink-based sensors, this technology could be used on piping or under waterproof tiles to detect leaks across wide areas of a building, thereby supporting immediate maintenance before liquids have time to cause significant damage. Such sensors communicate wirelessly with cloud systems whenever a change in humidity is detected, giving building managers unprecedented visibility.
Similar functionality has been developed for gas sensing in buildings. Using advanced materials such as carbon nanotubes, the conductivity of each material is changed by the absorption of gas molecules. By algorithmically analyzing the output from all the gas sensors in the array, the technology can determine the composition of specific gases. This method can be applied for safety applications for the detection of dangerous gases like methane or carbon monoxide but also for air quality by recognizing the level of carbon dioxide and other pollutants that cause occupant health and productivity issues.
According to a recent IDTechEx’s report, printable electronics already represented a market value of $6.3bn in 2013, the firm forecasts the market for printed sensors will have increased by another $1bn by 2020. This includes organic and hybrid photodetectors, piezoresistive and piezoelectric pressure sensors, stretchable strain sensors, temperature sensors, printed electrodes for skin patches, biosensors, ITO alternatives for capacitive touch sensors, and others. Printed and flexible sensors constitute the largest part of the printed electronics market. The market for fully printed sensors is forecasted to reach $4.5 billion by 2030.
The maturing of printed sensor technology represents a significant potential disruption of the smart buildings market. Their low-cost, lightweight, thin, and flexible form could bring about a new level of visibility for building managers across wide areas of their facilities for a wide range of building and occupant focused applications. Data collection has always been the basis of smart buildings and lower-cost sensors have always been the enabler of greater data collection, so roll-to-roll printable sensors can fundamentally change the smart building space forever.