The only mammals that are endemic to the island of Mauritius are bats. Any renewable energy projects must take the animals into account to balance clean power with the ecosystem.
Kite power generation is a niche sector of wind farming, and there is one system operating above some of the country’s cane fields.
The system is more compact than bladed turbines. But how does a kite manage to send significant energy to the grid while avoiding harming sky-borne wildlife?
How the renewable energy transition plays out on an island
The Airborne Wind Energy (AWE) pilot project has been operating on the east coast of Mauritius in the Indian Ocean for three years, tracing figure eights in the sky. The kite is operated by SkySails-Power Indian Ocean.
The hardware is the Venyo model, featuring a 1,292-square-foot sail for the Mauritius pilot project. While current Venyo configurations reach up to 200 kW with an expanded sail, public records list the installed capacity of the Mauritius unit between 100 kW and 150 kW.
Mauritius uses a lot of imported fossil fuels to power its grid, but the country is pushing to change this.
Standard wind turbines need to stand on large concrete foundations, and installation takes heavy construction and clearing of land.
Preserving the island’s natural forest habitat and working agricultural land is a major priority, according to the Government of Mauritius. The only native land mammals are bats. There are two species, the Mauritian flying fox megabat and the Mauritian free-tailed bat.
The airborne kite system gets around the space limits with lightweight tethered structures instead of tall steel towers. This pilot installation operates from a trailer on the ground near sugarcane plantations.
Airborne wind energy systems can use up to 90% less material overall than traditional wind turbines.
This minor footprint means that farming under the kite can carry on uninterrupted, demonstrating that high-altitude energy harvesting can be easily integrated into the island’s land use, according to Airborne Wind Europe.
The coexistence of wind kits and flying fauna
The benefits of kite systems go beyond the reduced land footprint. They are also able to coexist with wildlife.
Mauritius has rare bird species alongside the native bats. Collision risks are a serious concern on islands, but the way that kites work is unique. They are deployed in the air on a tether, and they form a much smaller barrier in the air than bladed models.
So far, environmental monitoring of the pilot site shows no impacts on bird or bat species.
The kite is also able to be reeled down quickly when the weather is too calm for generation or when wildlife movement is heightened.
The unit reaches altitudes of between 330 and 1,300 feet, so it accesses stronger, steadier winds high up while leaving the airspace below clear.
A high-altitude pumping cycle for power generation
The power kite generates electricity using a continuous two-phase pumping cycle.
During the power phase, an automated computer control system steers the kite in fast figure-eight loops at altitudes up to 1,300 feet. As strong crosswinds sweep over the foil, the kite pulls forcefully on a high-strength synthetic tether.
This tension unrolls the tether from a ground winch reel connected to a generator, spinning the shaft to produce electricity for the island grid.
A reel-in phase kicks in at 2,600 feet of tether
When the tether reaches its maximum length of roughly 2,600 feet, the system enters the reel-in phase.
The onboard controls tilt the kite’s angle of attack to flatten the foil, dropping its aerodynamic resistance. The ground winch then uses a small fraction of the generated power to quickly reel the kite back down to a lower altitude.
Because reeling in takes far less energy than the power phase produces, the cycle yields a net surplus of clean electricity.
After three years of continuous field operations over Mauritian cane fields, the pilot project shows that high-altitude power kites can supply steady electricity to island grids.
Combining a minimal ground footprint with flexible skyward flight gives Mauritius a practical renewable energy tool tailored to its specific land constraints and wildlife considerations.
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