Growing the Energy Harvesting Ecosystem

Whether it’s the Internet of Things, wearables, or industrial automation, many new devices and applications are portable and battery-operated. Wireless connectivity is required for connecting to the Internet. Today’s devices collect and transmit data from sensors, are always or almost always on and require power. The semiconductor industry has met the challenge to design devices for low power operation. Low-power microcontrollers and low-power RF are now available from many semiconductor vendors. But eventually batteries still run out of energy and have to be replaced or recharged.

The term energy harvesting, also known as power scavenging, is used to describe the creation of energy derived from a variety of external sources such as solar power, thermal energy, wind energy, kinetic energy or electromagnetic sources. Energy harvesters accumulate the wasted energy in a system, such as heat given off by motors or semiconductors, or the vibrations of motors or other moving objects. The basic technologies for generating energy are: mechanical vibration (kinetic energy), thermoelectric, solar (photovoltaic), and RF/Inductive.

An EH solution requires more than just the energy harvester or transducer. The key components include a power converter, power management IC (PMIC), MCU, and energy storage. The energy storage can be a rechargeable battery (Li-ion or thin film) or a super capacitor. It will be these components which offer potential growth for the semiconductor industry.
An ecosystem of semiconductor vendors is emerging for the nascent EH market. The ecosystems are gravitating around the vendors of key power components. They are forming partnerships with producers of energy harvesters, battery suppliers, and other components. EH development kits and reference designs are offered.

A few of the conventional, established semiconductor vendors in the EH ecosystem are Linear Technology, Maxim Integrated, Texas Instruments, STMicroelectronics, Atmel, Silicon Labs and Microchip. But there are also some new players trying to develop more innovative solutions with their EH technology.

Linear Technology offers several PMICs, power converters and battery charging circuits. The company has a long list of partners. In addition to over 16 suppliers of energy-generating transducers, Linear also partners with NXP (formerly Freescale) and Silicon Labs for MCUs.

Maxim Integrated offers the MAX17710, a complete system for charging and protecting micropower-storage cells. The company partners with Infinite Power Solution's THINERGY® microenergy cells (MECs). The PMIC works with a variety of energy-harvesting sources which do a poor job of regulating the energy such as solar and other low voltage energy generators.

Texas Instruments offers a variety of PMICs, power converters and battery chargers specific to EH. Atmel is focused on devices with low quiescent power and peripherals with low peak power. Atmel also has BLE and ZigBee (6LowPan) mesh solutions, as well as low power MCUs.

ST’s main activity is in developing solid-state micro-batteries for ultra-low power IoT applications. This is the EnFilm solid state battery, EFL700A39. The company is collaborating with energy harvesting companies (including Micropelt and Thermogen) to build and propose complete autonomous and Perpetual Energy Modules (PEMs) including energy storage, energy harvesting, and energy management circuits.

Silicon Labs has several products targeting EH such as low power wireless MCUs, ZigbBee and Bluetooth solutions. Microchip is offering MCUs with very low power consumption, and solutions for Bluetooth Smart. It has a portfolio of low-power analog that can be used for EH. For a full list of companies in this space, as well as their partners and products, contact Rick Vogelei at rickv@semico.com.

I released my first EH study in 2012, called “An Early Growing Season”. Although many of the solutions were available back then, the ecosystem continues to expand as more partnerships develop. For example, EnOcean, a spin-off of Siemens, has technology on the market for lights, switches and other industrial applications but does not have a solution to integrate into the existing world of wearables and other mobile applications. The ecosystem is offering more complete solutions to customers, and in my new report to be released this month, I highlight the leaders in this market.