Since the early 2000s, scientists have been working on developing new devices with the ability to harvest energy directly from the human body. Infections, risky procedures, and interfering cables are just a few of the most common problems with many medical devices, such as implanted electro-stimulators (e.g., diabetes treatments) and pacemakers, which are often necessary for many people’s survival. For instance, currently, 537 million adults (20–79 years old) are living with diabetes, with the number predicted to rise to 643 million by 2030 and 783 million by 2045 (International Diabetes Federation, 2022), whereas the number of people requiring peacemakers is estimated to rise to 1.43 million by 2023 (Stewart, 2022).
Fortunately, recent technological advancements have enabled those devices to consume significantly less energy, with the possibility of even becoming self-powered within the human body. As a result, overcoming the previously mentioned technical complications during recharging or battery exchange, which is often performed via intrusive surgeries to change the batteries in implanted devices such as pacemakers and electro-stimulators. That is exactly why these “electroceuticals” have the potential to transform the medical sector. Additionally, given the expanding market for wearable technology and the rising need for medical gadgets that promote healthy living, this invention is especially promising.
Here are some examples of solutions that will soon overtake the medical sector.
Energy in an avalanche effect
One example of a company striving to harvest energy from the human body is the German start-up CELTRO. The company has developed microneedles that can extract energy located in the action potential cycle of the living cell, where sugar as the primary energy carrier is transformed into electrical current, which is then used in nerve and muscle action (CELTRO, n.d.). When this process is repeated in hundreds or even thousands of human body cells, nanowatt-power is produced, which can be stored and later supplied to any medical component, such as a pacemaker. CELTRO’s CEO, Gerd Teepe, explains that by harvesting energy at multiple points in the heart, the company can utilize the “avalanche effect” of a muscular contraction.
Pendulum in the heart
Another startup worth observing is CAIRDAC. Based in Paris, the company is designing a pacemaker that is powered by the heart itself. The leadless pacemaker is contained in a capsule and uses a piezoelectric energy harvester, a pendulum that swings through heartbeats and blood flow, to convert the kinetic energy of the heart’s vibrations into electricity. The electricity is then stored, and once the device detects unevenness in the cardiac cycle, it sends an electric impulse that the heart requires to reset the rhythm (Cairn Medical Devices, n.d.). Moreover, their most prominent product, ALPS, is not only autonomous but can also be implanted endoscopically, decreasing the risk of procedural complications.
Solar panels under the skin
In addition to harnessing energy from heartbeats, researchers from Monash University in Melbourne, Australia, have developed new solar panel cells that could be implanted under the skin.
Experiments both under natural and artificial light sources have shown show that the solar panel covered by a 3 mm thick animal skin (porcine flap) can output tens of microWatts to a few milliWatts depending on the light conditions (Wu, 2018). This amount of electricity is enough to power an ultra-low consumption sensor, such as an implantable temperature sensor. Additionally, the results from tests on various body parts suggest that the optimal position for the implant is between the neck and shoulder. Moreover, those solar panels are not only extremely thin—10 times smaller than the width of a human hair—and flexible, but they can also be produced quickly and cost-effectively with continuous printing technology, which makes them perfect for wearable electronics (Monash University, 2018).
Extracting energy
Last, but not least, is a Swiss start-up. Mithras has redeveloped the application of thermoelectric generators, often used in high-temperature industrial solutions or even Mars rovers. Here, TEGs are used to create electricity through the Seebeck effect by exploiting the temperature difference between the body and the environment. As they point out, every day an adult body releases an average energy of 3 kWh, which is sufficient energy to run an LCD TV for 30 hours. Moreover, Mithras estimates that even a 5-degree Celsius difference between the body and the environment can generate enough energy to power, for instance, a cochlear implant (Mithras, n.d.).
What can we see in the future?
Researchers have been striving to harness energy from the human body since the beginning of this decade. We are still exploring this sector, nonetheless, the potential implications for the future are enormous, especially as healthcare apps and gadgets are trending. Furthermore, those technologies have the potential to eliminate the need for invasive surgeries to replace or recharge batteries in implanted medical devices, hence, patients will have a lower risk of complications associated with the procedure and be able to stay healthy longer. Additionally, by utilizing the human body as a power source, devices can be more space-efficient, lighter, and self-sufficient, providing patients with a more comfortable experience and a glimpse of normal life.
_____
Bibliography:
Dunlevy, F. (2023, January 19). Wired. The Battery That Never Gets Flat. Retrieved January 13, 2023, from https://www.wired.com/story/the-battery-that-never-gets-flat/?fbclid=IwAR3xSdhI0i32NfYC7An8WY5gE9W05nG1E7M4An_S4Qm71b3fo9GCyzc6jms
International Diabetes Federation. (2022). Diabetes Atlas. Retrieved January 13, 2023, from https://diabetesatlas.org/
Stewart, C. (2022, April 20). Statista. Pacemakers Market Volume in Units Worldwide. Retrieved January 13, 2023, from https://www.statista.com/statistics/800794/pacemakers-market-volume-in-units-worldwide/
CELTRO. (n.d.). Wireless Energy Transmission. Retrieved January 13, 2023, from https://celtro.de/
Cairn Medical Devices. (n.d.). Improving Lives Through Innovation. Retrieved January 13, 2023, from https://www.cairdac.com/
Wu, T. & et all. (2018, July 19). A Wireless Implantable Sensor Design With Subcutaneous Energy Harvesting for Long-Term IoT Healthcare Applications. IEEE Access. Retrieved January 13, 2023, from https://researchmgt.monash.edu/ws/portalfiles/portal/256379021/253854691_oa.pdf
Monash University. (2018). Ultralight, flexible solar cell keeps tech in shape. Retrieved January 13, 2023, from https://www.monash.edu/news/articles/ultralight,-flexible-solar-cell-keeps-tech-in-shape
Mithras. (n.d.). Innovative Blockchain and Cryptocurrency Solutions. Retrieved January 13, 2023, from https://mithras.tech/
Very interesting article! It’s quite thrilling to see technology advance to the point where it’s possible to directly collect energy from the human body. Fantastic work is being done by companies like CELTRO and CAIRDAC to develop medical devices that can function without cables, infections, or other external power sources. The tiny, flexible solar panels developed by Monash University are of special interest to me since they might have a big impact on wearable electronics. Future developments in these technologies will be interesting to see since they might have a significant impact on healthcare.
Thank you for sharing this knowledge!