The ultimate success of wearable Health Tech devices depends in large part on their ability to do more using less power. Better batteries can help device run longer between charges, such as the ARC Centre of Excellence for Electromaterials Science work with biodegradable silk batteries and MIT spinoff 24M’s use of colloidal suspension of particles in battery design. The real solution will require components that consume less power in the first place, such as PsyKick, another MIT offshoot, with its ultra-low power consumption processor and a low-power chip for hearables under development at MIT.

Temperature measurement is one of the most common sensor categories. Taking someone’s body temperature is key to detecting fever or monitoring tiny temperature pattern shifts to predict fertility windows. Researchers at the University of California, San Diego  – Davis Jacobs School of Engineering have developed a temperature sensor with near-zero power requirements. The sensor needs only 113 picowatts of power, 10 billion times smaller than a watt. That power need is 628 times lower than currently available state-of-the-art temperature sensors, according to UC San Diego. This is accomplished by using the “gate leakage” that occurs in some transistors; while it is a problem for some applications, it turns out to vary with temperature and thus can be measured. This “near-zero” power requirement could extend the useful life of implants and wearables and have additional applications in smart home monitoring, IoT devices, and environmental monitoring systems. The only drawback appears to be that the sensor can only produce a reading once per second or so, which is not a problem for most applications.

According to Patrick Mercier, an electrical engineering professor at the UC San Diego, the power requirements for this new sensor technology are so low that they could be provided by energy harvesting, which could completely eliminate the need to recharge the devices that use them.