DARPA is developing a wireless power grid using lasers

The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense dedicated to developing new technologies for military use.

Among its most innovative projects is the Continuous Wireless Optical Power Relay Program (powerfor its abbreviation in English), which seeks to create a wireless power network using lasers.

The goal of POWER is to transfer electrical energy from the source to the receiver through a beam of laser light, without the need for cables or physical connections.

This would allow the operation of remote devices, such as drones, sensors or satellites, that do not have access to traditional power sources or require a significant degree of autonomy and mobility.

Wireless optics

To achieve this, POWER relies on the concept of wireless optical relays, which are devices capable of receiving, amplifying and retransmitting laser energy. These relays will be placed on aerial platforms, such as balloons, airplanes or helicopters, and will form a network that can cover long distances and overcome ground or air obstacles.

according to Paul JaffeDARPA’s POWER program manager, explains in a launch This technology has the potential to “exponentially enhance energy transmission” and create a “flexible, lightweight” power grid.

In addition, he stated that laser energy transfer could have civilian applications, such as wireless charging of electric vehicles or remote access to renewable energy sources.

Three stages

The POWER program is divided into three phases: the first phase consists of the conceptual design of optical relays; The second is to integrate these relays into capsules that can be transported by aerial platforms; The third is in a demonstration Transmit 10 kilowatts of laser energy over a distance of 200 kilometers.

To carry out this project, DARPA has appointed three teams led by BEAM, Draper and RTX Corporation. Each team will have to develop their own optical relay design and demonstrate its operation in a real environment. Relays will be evaluated according to their efficiency, accuracy, quality and regulation of transmitted energy.

The POWER program began in 2020 and is scheduled to have a four-year duration, so it is nearing the end of its development process. If the goals and deadlines are met, DARPA could achieve a historic breakthrough in wireless power transmission and open doors to new possibilities for using and harnessing electrical energy.

The transfer of energy

Power transmission is a technology that allows electrical energy to be sent from one place to another without cables or physical connections. This can be achieved using electromagnetic waves, such as microwaves or lasers, which transmit energy through air or space. Power transmission has many potential applications, such as powering remote devices, electric vehicles, satellites, or even lunar bases.

The basic principle of energy transmission is to convert electrical energy into a form of electromagnetic radiation, emit it from a source or transmitter, and capture it with a receiver or transmitter. Straight (Antenna correction) and convert it back into electrical energy.

The transmitter and receiver must be aligned and tuned to the same frequency and wave polarization. Transmission efficiency and safety depend on many factors, such as distance, angle, weather, obstacles, and interference.

Advantages and challenges

Power transmission offers some advantages over traditional power distribution methods, such as reduced resistance losses, elimination of cables and towers, flexibility and mobility, and the ability to access remote or otherwise inaccessible renewable sources. In addition, energy transfer can facilitate the development of space systems, such as orbiting solar arrays or planetary missions.

However, energy transportation also poses some technical, economic and social challenges. Technical aspects include component design and optimization, beam control and stability, mitigation of atmospheric impacts, integration with existing power networks, and compliance with standards and regulations.

Economic aspects include the cost and profitability of infrastructure, market and competition, incentives and subsidies. Social aspects include environmental and health impact, public acceptance and trust, and ethical and geopolitical implications.

Technical news

However, energy transfer is not a new idea. In fact, it was first proposed by Nikola Tesla at the beginning of the 20th century. However, the first successful experiments using microwaves and lasers were not carried out until the middle of the last century. Since then, many projects and research have been carried out in different parts of the world, both on Earth and in space.

Relative to previous wireless power transmission technologies, POWER differs in several ways.

Firstly, in the energy transfer method: POWER uses lasers, while other projects use microwaves, radio waves or ultrasound.

Second, in the network structure: The POWER system relies on wireless optical relays located on aerial platforms and forms a network that can cover long distances and overcome ground or air obstacles. Other projects may use fixed antennas, satellites, or drones.

It also differs in the project’s goal: POWER seeks to transmit the aforementioned 10-kilowatt laser energy over a distance of 200 kilometers, with which it could power remote devices, electric vehicles or satellites. Other projects may have different goals, such as transmitting solar energy from space, charging mobile devices wirelessly, or delivering high-speed data.