Makani 30kW prototype high altitidue wind turbine in flight

What is Airborne Wind Power?

Summary

The Makani AWT is a tethered, autonomous wing fitted with onboard turbines for power generation. Flying at 1,000 ft, the system mimics the motion, and speed, of a conventional turbine’s aerodynamically effective blade tips.

The following video depicts an onshore installation of Makani’s AWT.

Click the arrows to advance through the video.

More Video: Flights

Read On: What are the benefits of Makani’s approach?

  • AWT

    A wind based energy generation device with at least one airborne element. The Makani AWT consists of a rigid wing with mounted turbines that flies in circles across the wind at 300 meters (1,000 feet) above ground level.x

    Airborne Wind Turbine

    A wind based energy generation device with at least one airborne element. The Makani AWT consists of a rigid wing with mounted turbines that flies in circles across the wind at 300 meters (1,000 feet) above ground level.x

    Airborne Wind Turbines

    A wind based energy generation device with at least one airborne element. The Makani AWT consists of a rigid wing with mounted turbines that flies in circles across the wind at 300 meters (1,000 feet) above ground level.x

    Autonomous Controller

    An on-board computer that controls the flight path of the wing by changing the position of the control flaps.x

    Avionics

    The electronic backbone of the AWT. Avionics include the sensors, actuators, controllers and communication systems that keep the wing flying on its desired path.x

    Capacity factor

    The average power output divided by the name plate power output of a power plant. Capacity factor demonstrates the frequency with which a power plant is running at its name plate capacity.x

    COE

    Cost of Energy or the total cost to generate energy that is fed into the grid.

    Firming Power

    The outside power generation needed to stabilize the flow of electricity to the grid when an inconsistent resource, like wind or solar, creates less electricity than needed.x

    Ground Station

    The base station for the AWT, includes a winch for retrieval of the wing and storage of the tether.x

    Car vs. AWT

    A typical compact car weighs about 1.2 tons and produces about 30 kW during the 10 seconds it takes to slow from 25 m/s (50 mph) to a stop. Each cubic meter (~1.2 cubic yards) of air weighs only .0012 tons and a good wind day might be traveling at 25 mph (11 m/s), so Wing 7 would have to to interact with 350 cubic meters of air (about 23 dump trucks worth) every second to extract an equal amount of power. In reality it is not as efficient to design an AWT to completely halt the air it interacts with, so we design our AWTs to exert a smaller force on an even larger body of air.x

    Material efficiency

    Material efficiency refers to how much power is output in relation to the raw material needed for construction of the generator.x

    Rated power

    The amount of power a plant delivers when operating at full capacity.x

    Rated capacity

    The amount of power a plant delivers when operating at full capacity.x

    Rotors

    The rotors capture the accelerated wind as it rushes across the wing and convert it into electrical power with small, direct drive generators. The hybrid rotors can act as propellers as well as turbines, allowing the wing to stay aloft if the wind dies.x

    Turbines

    The rotors capture the accelerated wind as it rushes across the wing and convert it into electrical power with small, direct drive generators. The hybrid rotors can act as propellers as well as turbines, allowing the wing to stay aloft if the wind dies.x

    Tether

    The tether is made of high strength fibers surrounding a conductive core. The tether carries the traction force of the wing and transmits the electrical power to the ground station.x

    Tethered

    The tether is made of high strength fibers surrounding a conductive core. The tether carries the traction force of the wing and transmits the electrical power to the ground station.x

    Usable land

    Factors that influence whether land is usable include site geography, ecology, and wind patterns, for example. x