But unfortunately, the research in this field has been delayed for a century. The biggest obstacle is that transmission efficiency is too low and dangerous. Electromagnetic radiation is only suitable for transmitting information, not energy. Because radiation has no directionality, energy will be wasted in useless space. Some people imagine using directional electromagnetic radiation, such as laser, but it is not feasible and extremely dangerous.
Professor Xu Shuyuan from the Department of Electronic Engineering of City University of Hong Kong successfully developed a "wireless battery charging platform" a few years ago, which can put a variety of electronic products on a charging platform and automatically charge them through low-frequency electromagnetic fields, without external wires, and the charging time is the same as that of traditional chargers. However, this technology still needs the product to contact the charger, mainly using the principle of near-field electromagnetic coupling.
Researchers at MIT have made new progress in wireless power transmission. They used a power supply two meters away to light a 60-watt light bulb "every other place".
Soglia Qiqi's design, non-radiation wireless energy transmission has a distance limit, and the smaller the receiver, the shorter the distance. He calculated that an object the size of a laptop can receive wireless energy transmission within a few meters. "In this way, by installing a transmitter in each room, you can power the laptops in the whole house."
Soglia Qiqi hopes to improve the efficiency to 70% to 80% by using different materials and improving technology. They believe that the improved equipment will wirelessly charge laptops, mobile phones and other devices within three to five years.