PowerLight Technologies is an American engineering firm providing power transmission via

laser A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radi ...

s. Its primary products are

power-over-fiber Power-over-fiber, or PoF, is a technology in which a fiber-optic cable carries optical power, which is used as an energy source rather than, or as well as, carrying data. This allows a device to be remotely powered, while providing electrical is ...

which transmits energy in the form of laser light through an optic fiber, and "laser power beaming" in which the laser energy is transmitted through free space.

History

The predecessor to PowerLight Technologies, LaserMotive, was founded in 2006 by physicists Tom Nugent and

Jordin Kare Jordin T. Kare (October 24, 1956 – July 19, 2017) was an American physicist and aerospace engineer who researched laser propulsion. He was responsible for Mockingbird, a conceptual design for an extremely small (75 kg dry mass) reusable ...

. The company's initial goal was to win the NASA Centennial Challenges Power Beam challenge. After winning the challenge, LaserMotive focused on developing the power beaming technology for commercial application on

UAV An unmanned aerial vehicle (UAV) or unmanned aircraft system (UAS), commonly known as a drone, is an aircraft with no human pilot, crew, or passengers onboard, but rather is controlled remotely or is autonomous.De Gruyter Handbook of Drone ...

s and successfully demonstrated the transfer of 400 watts of power over 1 kilometer. In 2017, LaserMotive changed its name to PowerLight Technologies, hired three new advisors, and officially announced the launch of commercial applications for its power-over-fiber technology. The company's new CEO Richard Gustoffson described this new focus on power-over-fiber as a "major transformation" for the company. PowerLight also continues to work toward commercial application of its technology to free-space power transmission.

Technology

The power beaming system uses a laser running from a

power supply A power supply is an electrical device that supplies electric power to an electrical load. The main purpose of a power supply is to convert electric current from a source to the correct voltage, electric current, current, and frequency to power ...

. To define the beam size at its destination, the laser's light can be shaped by a set of optics. This

light energy In physics, and in particular as measured by radiometry, radiant energy is the energy of electromagnetic and gravitational radiation. As energy, its SI unit is the joule (J). The quantity of radiant energy may be calculated by integrating radian ...

can be sent through air or the vacuum of space, onto a

photovoltaic Photovoltaics (PV) is the conversion of light into electricity using semiconducting materials that exhibit the photovoltaic effect, a phenomenon studied in physics, photochemistry, and electrochemistry. The photovoltaic effect is commercially ...

(PV) receiver, where it is converted back into electricity. In addition to delivering energy through air or space, PowerLight adapted the technology to deliver electricity through an

optical fiber An optical fiber, or optical fibre, is a flexible glass or plastic fiber that can transmit light from one end to the other. Such fibers find wide usage in fiber-optic communications, where they permit transmission over longer distances and at ...

. By transmitting a focused laser light through optical fiber to a solar cell-like receiver, this technology allows for power to be provided over hundreds of meters in environments where electric transmission by copper wire is not optimal, either due to the higher weight of wire compared to glass fiber, or due to operational constraints imposed by electromagnetic fields generated by electrical transmission by wire. Uses include ground, air, and underwater applications. The electrical-to-optical

conversion efficiency Energy conversion efficiency (''η'') is the ratio between the useful output of an energy conversion machine and the input, in energy terms. The input, as well as the useful output may be chemical, electric power, mechanical work, light (radia ...

of modern laser technology can be as high as 85%, and off-the-shelf semiconductor diode lasers can have an output efficiency of around 50%. The optical-to-electrical conversion efficiency of a photovoltaic receiver can be over 50% for monochromatic (or laser) light.

Applications

PowerLight Technologies has investigated numerous applications for its laser power beaming technology, including transmission of power both to and from the ground, spacecraft, aerial vehicles, satellites, and a lunar rover.

Tether propulsion

The company's stated first goal was to win the

Beam Power Challenge Elevator:2010 was an inducement prize contest with the purpose of developing space elevator and space elevator-related technologies. Elevator:2010 organized annual competitions for climbers, ribbons and power-beaming systems, and was operated by a ...

, part of the Space Elevator Games, to power a small climber up a vertical

tether A tether is a cord, fixture, or flexible attachment that characteristically anchors something movable to something fixed; it also may be used to connect two movable objects, such as an item being towed by its tow. Applications for tethers incl ...

. They partnered with

The Boeing Company The Boeing Company, or simply Boeing (), is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, and missiles worldwide. The company also provides leasing and product support s ...

, which provided them with test facilities, as well as specialized solar cells. In 2007, they failed to qualify for the Challenge due to difficulties meeting

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

's specifications. At the 2009 Challenge, on November 6, 2009, LaserMotive successfully used lasers to drive a device up a cable suspended from a helicopter. Energy is transmitted to the climber using a high-power infrared beam. LaserMotive's entry, which was the only one to top the cable, reached an average speed of and earned a $900,000 prize. This marked both a performance record, and the first award of a cash prize at the Challenge.

Aircraft propulsion

On October 28, 2010, PowerLight set a flight endurance record at the Future of Flight Center by powering a

quadcopter A quadcopter, also called quadrocopter, or quadrotor is a type of helicopter or multicopter that has four rotors. Although quadrotor helicopters and convertiplanes have long been flown experimentally, the configuration remained a curiosity ...

for more than 12 hours using infrared semiconductor diode lasers to power a small photovoltaic array. The vehicle was equipped with a small on-board battery capable of only a few minutes of flight. On August 7, 2012, PowerLight equipped a Lockheed Martin Stalker UAS with a laser receiver, and the system was successfully demonstrated during day and night operations in the desert. This series of demonstration flights is described as "the first-ever outdoor flight of a UAS powered by laser".

References

External links

* {{Space elevator Engineering companies of the United States Laser companies Space elevator Companies based in Kent, Washington Wireless energy transfer