Firstly, we will talk about the term Microwaves, Microwaves can also be termed as Radio waves having wavelengths ranging from one millimeter to one meter and the frequencies from 300MHz to 300GHz. These are also known as millimeter waves. These waves can also be used for power transmission in such a way, by converting DC power to microwaves and then by using antenna, these are transmitted, and after that rectenna receive those waves and converts them into DC again which can be further inverted into AC. The basic components include microwave source, an antenna for transmission, and a rectenna as a receiver. It has many applications such as it is used for power supply purpose in orbital lift space ships.
After the World War II, we saw the development in high-power microwave emitters, also known as Cavity magnetrons, and this lead to the idea of using microwaves for power transmission. In 1964, William C. Brown demonstrated the working of rectenna in helicopter as it converts microwave power into electricity, and is capable of achieving high efficiencies over 90%. Now it is commonly used for transferring energy to the surface of earth from solar power satellites. Numbers of researches are made. In 2008, an experiment of long range power transmission was performed and successfully transmitted 20 watts up-to 92 miles.
Microwave Power Transmission is very efficient way of transferring power from one place to another, wirelessly. With the passage of time, its applications in daily life are increasing because of its efficiency. It is also perceived by the people that microwaves are very dangerous as they are used in microwave ovens but, it would be safe enough as the power level would be equal to the leakage but slightly more than the leakage from the cell phones. It has been also researched on multiple generations of animals by exposing them to microwave radiations of high intensity but no health issue was found.