Makani power: The rise and fall of Google's flying energy solution

How can we efficiently produce clean energy? One idea was presented by Makani Power, a company that developed flying power plants. Over the years, it tested several different working prototypes, but the company was eventually shut down despite being acquired by Google.

Makani Power's idea sought to address the limitations associated with ground-based wind turbines. These turbines are constrained by factors such as the availability of suitable land and regulations governing the distance between turbines and residential buildings.

Variable wind, which does not always blow with sufficient force, also hampered the efficiency of ground-based turbines. Makani Power, founded in 2006, proposed a solution to these limitations.

Rather than constructing ground-based energy infrastructure, Makani Power decided to elevate the plant to a height of several hundred metres. By adjusting the operating altitude, they could find optimal wind conditions, maximising the plant's potential.

The flying power plant resembles a motor glider combined with a kite, which takes off and ascends vertically with its tail pointed downwards. After reaching the desired altitude, the tethered "glider" circles, and the wind propels the turbine rotors. The electricity is transmitted to the ground via a cable.

Energy is generated at altitude, which presents certain challenges – the mass of the generators must first be elevated hundreds of metres above the ground (Makani's competitors addressed this by leaving the generators on the ground).

Makani Power was connected to Google from the start. Founded in 2006 with a grant awarded by Google under the RE>C programme (Renewable Energy Cheaper than Coal), it was acquired by Google in 2013 after one of its founders passed away and was assimilated into the portfolio of initiatives developed under Google X, a research centre where Google innovates on promising technologies.

Although Makani built increasingly larger prototypes (one of which was lost) and received investment from Shell, among others, in 2020, Alphabet, formed from Google's restructuring, decided to close Makani Power. The official statement cited the unexpected complexity of commercialising the invention as the reason for the closure.

Despite this, Alphabet decided to publish the technical documentation for the equipment, release the software source codes, and declare the abandonment of patenting the developed solutions to allow others to continue working on flying power plants.