ENERGY HARVESTING TECHNOLOGY

Do you know electronic devices are extremely power-hungry? How much power will they ever need throughout their lifetime?

Limitless, right.

Nowadays it’s difficult to find a successful business without the use of electronic devices. So, it becomes very important to find an alternative resource that will be reliable and cost-effective as well. As usual, technology has found a reliable solution to this problem as Energy Harvesting Technology.

In simple words, Energy harvesting is the process by which energy is derived from external sources such as sunlight, wind, heat, water, radiation, vibration and motion, etc. and stored. These processes are also known with different names such as power harvesting or energy scavenging or ambient power.

As we all know, the biggest source of energy is solar energy and it also provides the limitless power supply. But sadly, it is only working when the sun is shine. That is why we need to find other power harvesting alternatives.

Again, technology has shown its miracle and introduce the world with RF energy harvesting. RF Energy harvesters can collect free energy from just about everything, like overhead power lines, coffee machines, refrigerators, or even Wi-Fi router or smartphone emissions. This may sound like pseudoscience of hocus-pocus, but the underlying science is surprisingly sounding.

Now you might wonder “What is RF Energy Harvesting system?”.

Essentially, each electrical device emits electromagnetic radiation — and if that radiation passes through a wire coil, an electrical current is produced. So, in simple words, it is the system that captures RF energy and converts it into Electric energy with the help of RF-based harvesters and wireless sensors. Nowadays, there are a lot of RF sources exist in the world such as Wi-Fi networks, mobile phone networks, radio broadcasting, TV broadcasting. With these RF sources, there is a lot of RF energy exists in the environment. Since RF energy available all the time & everywhere. Therefore, RF energy harvesting technology would be a good potential for electronics applications such as medical implants, wireless sensors, remote monitoring applications, wearable devices, small wireless autonomous devices. (like smartphone, smart wristwatches, fitness trackers, a pocket calculator and wireless sensor networks, such as temperature, sound, pressure, etc.) and IoT application.

There are several other reasons why companies should invest in RF energy harvesting. It helps the company in many ways:

1. Reduce the cost associated with the powering system
2. Boundless supply (self-sustainable)
3. Ample energy solution (Unlimited usage)
4. Readily available (anywhere)
5. Suitable for various development at an unreachable location
6. Feasible and safe.

It also helps to solve many environmental issues like:
• Global Warming result from excessive fuel burning
• Outpouring oil prices because of growing market demand
• Pollution caused by burning and oil spill
• To reduce dependency on batteries

When it comes to harvesting electrical power from non-traditional power sources, we generally use different technologies like thermoelectric generators, piezoelectric transducers, and solar cells, etc. these processes are always remaining a challenge. All of these need a form of power conversion circuit for efficiently collecting, managing, and converting the energy from these sources into usable electrical energy for wireless devices, microcontrollers, sensors, and other low-power circuits.
System block diagram:

• The antenna is an integral part of the rectenna which should possess several requirements to harness the ubiquitous RF energy and convert it into an output DC voltage. Usually, circularly polarized antennas are preferred in rectenna designs because they can receive both linearly and circularly polarized RF signals without any polarization loss.
• Impedance-matching network is the most important part of a rectenna design. It was found between the antenna and the rectifier. The RF to DC conversion efficiency greatly depends on the rectenna’s impedance-matching network.
• The rectifier is also called a charge pump. Three basic types of rectifiers are used.
◦ 1. standard rectifier
◦ 2. voltage doubler
◦ 3. voltage multiplier.
• A high RF to DC conversion efficiency is required for the rectifier. To achieve this, it is Implemented through one or more diodes. The choice of the diode is very critical because it can be a major source of loss. The overall efficiency of the system depends upon the diode’s performance.
• A standard low-pass filter is used. It should consist of a capacitor connected in parallel with the load. It is typically used to filter out the higher-order harmonics from the DC component that is provided to the load.

Energy harvesting is a rapidly growing industry. In 2009 the energy harvesting market was $79 million. Recently a reliable market research firm has estimated that energy harvesting components will exceed $4 billion by 2020 resulting in an average annual growth rate of over 73%. The current market leaders are Europe, North America, Japan, and China.

Optimized Solutions develops energy harvesting solutions for multiple markets, including consumer electronics, wearable devices, and the Internet of Things. Based on our years of experience working in this filed, we have innovated a specialized IP and techniques to address the challenges of energy harvesting applications