As IoT devices are adopted in various fields, the energy harvesting industry, which can be called an IoT-mediated industry, is also emerging. Energy harvesting design, which is gaining attention as an alternative power source along with the benefits of introducing renewable energy, is leading the latest trend in IoT.

Mouser Seminar 2024 was held on the 2nd at the COEX Conference Room in Samseong-dong, Seoul, under the theme of 'Latest Technologies for IoT and Energy Harvesting Design'.

Kim Gwang-ho, partner at Roland Berger Consulting, explained, “IoT has existed for a long time, but we predict that initiatives for growth are gradually being expressed recently.” He added, “At this point, the trend of monetizing a large amount of information by collecting it and converting it into business insights is accelerating due to the advancement of cloud, edge computing, and communication technologies and the entry into the Industry 4.0 era.”

Energy harvesting is an industrial technology with a large demand market in the IoT, and its growth is in line with the IoT. Partner Kim Gwang-ho emphasized that “energy harvesting is expected to record an average annual growth rate of about 20% from 2024 to 2030,” which is higher than the IoT market growth rate of 13%.

The basic type of energy harvesting is the existing method of converting light energy into electrical energy, which was often adopted in calculators in the past. This is a relatively simple module and can be designed efficiently at low cost, but has the disadvantage of lacking power in indoor environments where light energy is insufficient.

Another method is electromagnetic. It collects waves and vibrations as electromagnetic waves and converts them into electricity. Energy can be obtained from waste electromagnetic waves such as broadcast waves, mobile communication waves, and Wi-Fi, so it can secure a virtually permanent power source in modern environments.

Thermoelectric energy is a method of harvesting energy by utilizing residual heat and waste heat from the human body and machines, and generates energy by utilizing the scientific principle that current flows due to temperature differences. It is characterized by high durability.

Piezoelectricity (Kinetic Energy) utilizes piezoelectric elements that can harvest energy through vibration and pressure. It can convert electrical energy from vibrations and shocks that occur in daily life, and energy can be harvested from vibrations of machines, roads, and stairs. It is characterized by high energy output efficiency and high visibility of input-output conversion.

Major players supplying products include: △Optoelectronics (EXEGER, ST, ADI, EnOcean, Microchip, e-peas, ONiO, etc.), △Electromagnetics (Powercast, ONiO, e-peas, WePOWER, Qorvo, etc.), △Thermoelectrics (ABB Group, EnOcean, ST, e-peas, etc.), and △Piezoelectrics (Piezo.com, EnOcean, e-peas, etc.).

Partner Kim Gwang-ho evaluated that “it is difficult to say that the energy harvesting market size is very large as it is still in the growth stage, but the barriers to technology and market share are not high,” and mentioned that the market appears to be fragmented and there are few competitive players.

In addition, it was introduced that real-demand energy harvesting solutions targeting micro solutions such as energy sources for IoT sensors linked to agriculture and supplying energy sources for IoT sensors and switches in places with dense floating populations such as smart cities are advancing into the market.

This energy harvesting is introduced as a technology that can also solve the battery problem of IoT. Lee Kyung-bo, director of Silicon Labs, gave a presentation on the topic of 'Energy-efficient wireless SoC for battery-less IoT' and said that batteries are slowing down the growth of IoT.

All batteries eventually need to be replaced, and the only way to improve battery life is through rechargeable or battery-less designs. The battery-less IoT architecture consists of an energy harvesting unit, a power management IC, rechargeable and backup batteries or alternative battery technologies, sensors, and an IoT radio and MCU.

Energy harvesting elements are embedded for battery-powered or battery-less designs. Silicon Labs explains that photoelectricity, vibration and piezoelectricity, electromagnetic waves, and thermoelectricity can be used as energy sources for applications that require a constant energy supply or are rechargeable, and piezoelectricity and triboelectricity can be used as energy sources for applications such as door locks and smart buttons that frequently go into deep sleep or power off.

Silicon Labs, which is releasing a family of low-power wireless SoCs that support a variety of batteries, announced that it will be hosting a TechTalk webinar on the 9th to unveil a new Bluetooth SoC for energy harvesting.