An IoT without batteries is the dream for making the concept viable for a world with a trillion nodes and a human population that will not be large enough to change all those batteries. The key to creating a sustainable IoT, and indeed a more sustainable world in general, is to harvest renewable energy to power smaller end devices so that batteries are no longer required in the design.
ipXchange has covered a few different energy harvesting solutions in the relatively short time we’ve been producing content, so here are five semiconductor manufacturers that are doing great work in the field, with chipsets that you can use in your next commercial project.
Atmosic has developed embedded solutions, such as the ATM3330e Bluetooth SoC, that are designed to work with the extremely low power consumption required by batteryless end products. The difference with Atmosic’s solution is that RF energy harvesting is built into the SoC, with a dedicated antenna serving as a collector for all the RF noise pollution that surrounds us in the modern world.
In stark contrast to micro-renewable power via ambient light energy, the dark is not an issue for RF energy harvesting, but the additional support for photovoltaic, thermal, motion, and other sources of micro-renewable energy makes Atmosic seem like the all-in-one solution. The addition of Bluetooth functionality and a 64-MHz Cortex-M33F MCU with DSP almost seems impossible to run without batteries, but Atmosic may have cracked it, and the ipXchange team saw a few different end products at Embedded World 2023, including medical devices, bicycle computers, and remote controls.
Though the power consumption is marginally higher than e-peas’ solution at 1.1 µA current draw in hibernate mode and 400 nA current draw with the SoC off (700 nA with harvesting enabled), Atmosic may be the Bluetooth SoC you need for a batteryless end product, so learn more on the dedicated board page and put it to the test by filling out a form.
The company that ipXchange first encountered that illustrated the unsustainable growth of IoT on batteries is Everactive, who have invented wireless IP and protocols that can be powered from low levels of ambient light – harvested through a solar panel – and small temperature differentials. Additionally, the technology is optimised for hyperscale IoT networks with up to 1000 nodes per gateway and a range of hundreds of metres. Everactive’s wireless protocol also boasts high building penetrability thanks to its sub-GHz signal basis.
This technology is demonstrated beautifully with a batteryless kit that consists of sensor ‘pucks’ which measure temperature, humidity, pressure, triaxial acceleration, and magnetic field as a basis for useful data that may be important for typical IoT applications. Rather than purely catering to energy harvesting for powering other components, Everactive’s solution takes a stand to provide designers with the low-power basis for decreasing the power consumption of IoT end nodes in general.
If you want to learn more or apply to evaluate this technology, follow this link to our dedicated board page to start your journey with Everactive.
This discovery at Maker Faire Rome was particularly interesting as Acme Systems have been developing the technology for nine years but have only just managed to get it to market. While Everactive’s technology uses a proprietary wireless protocol, Acme Systems’ H10 module uses LoRa, which is a much more common communication protocol for IoT systems. The key difference with most LoRa solutions is that H10 can operate purely on solar power and continue functioning in darkness for weeks at a time with the energy stored in a compact hybrid supercapacitor.
Despite having a Cortex-M0+ core running at up to 48 MHz, Acme Systems have managed to reduce the power consumption of H10 to as low as 4.29 µW (1.3 µA @ 3.3 V) in standby mode, enabling operation in no-light conditions thanks to automatic data transmission frequency reduction when the system detects that it is no longer harvesting energy; the Berta H10 evaluation platform can operate in no-light conditions for up to 100 days in standby mode. With full charge achieved in just 15 minutes of outdoor light exposure and harvesting still viable at less than 50 lux, power loss is extremely rare in any non-enclosed application.
Truly Acme Systems have made nine years of development worthwhile, so if you’re using LoRa as your primary communication protocol, learn more about H10 on the dedicated board page where you can apply to evaluate this new entry to the market.
Anyone that has interest in micro-renewable energy harvesting is truly doing themselves a disservice if they don’t know about e-peas, especially considering how good their exhibition game is. ipXchange first talked with e-peas at Electronica 2022, where they were demonstrating a kinetic energy harvester that enabled the transmission of a Bluetooth pulse using the physical click of a switch to power the circuit. That Bluetooth pulse could then be used to control a device such as the lighting for a home, the advantage being that it enables light switches around the home to be completely disconnected from the mains and simultaneously not require batteries for remote control of mains-connected lighting rigs.
Since then, e-peas has continued its development of numerous energy harvesting chips, of which ipXchange has primarily focussed on those for solar energy. The first thing to note is the ease of implementation for e-peas’ solar energy harvesting chips, as they typically require only four external passives for design in. For compact end products, this is a big win, and e-peas have recently unveiled new devices optimised to enable batteryless TV remote controls and wireless computer peripherals. That is surely something the consumer market should be hungry for.
Additionally, e-peas has also developed the EDMS105N MCU, a Cortex-M0 device with a maximum operating frequency of 24 MHz and an active current draw of 18 µA/MHz; the DeepSleep current is just 340 nA! Like the previous manufacturers in this article, e-peas are deep into development of technology that is able to run effectively using purely harvested energy sources, so learn more about each of the solutions that ipXchange has covered here, where you can apply to evaluate any of these technologies for your next design.
Tired yet from all that information? You need more than just some micro-renewable energy, so grab yourself a cuppa, and learn more by following any of the links above. ipXchange will be glad to help you play your part in a more sustainable future if you choose to fill out an application form to evaluate the technology.