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Google-owned Makani, a wind energy company at Alameda Point, moved one step closer last week to full-scale testing of its flying electricity kite. The novel invention made a rare public appearance at the company’s test site near the USS Hornet to fine-tune the docking maneuver. It will be deployed at a test site being readied in Hawaii where it will reach an altitude of 1,100 feet.

The wind energy craft was pioneered at Alameda Point. It employs the same principle as a stationary wind turbine, using the wind to rotate a blade connected to a generator. But unlike a traditional wind turbine, the tethered energy kite can soar to twice the height, accessing stronger wind force, while using a fraction of the materials. Electricity is transmitted to the base through the tether.

One of the big engineering challenges has been to design how the kite will launch itself into the air from a docking tower and then return when the wind dies down. An earlier prototype was tested on the former Navy airfield while tethered to a truck-mounted base.

The new model has three times the wingspan and twice as many motors and generators as its predecessor. The 84-foot carbon fiber craft uses eight motors to vertically take off and land on its base tower. Once airborne, the motors turn off, and the blades begin driving generators as the kite rotates in the wind.