Making AIR turbines even better with Highly Accelerated Life Testing (HALT)

Over the years, we’ve learned a few things about building the best wind turbine in the market. AIR has gone through a series of continuous refinements from the AIR 303, AIR 403, AIR-X and AIR Breeze. Each successive model has been more successful – in fact, AIR is still the world’s best-selling machine; with more than 135,000 units sold. Even with this success, there is always room for improvement. As technology advances and we learn about people’s needs, we evolve our products to do more while fulfilling customer expectations.

Today we’re releasing our latest and most reliable generation of AIR turbines: the AIR Breeze Marine, for sailing and off-grid coastal applications, the AIR 40, for off-grid remote homes, industry and telecommunication towers in non-corrosive environments, and the AIR 30, for hobby, RV and educational use.

The latest designs required a great deal of efforts on the part of our engineers as well as independent laboratories which helped us pinpoint weak spots in our products. Specifically, the most common causes of failures were excessive heat build-up during extreme wind events and mechanical stresses on the circuit board.

What did we do?

Southwest Windpower is probably the only small wind company with its own wind tunnel. Our engineers gathered information from warranty claims and in-house and external product analysis. We then duplicated identified problems in our wind tunnel and then began the process of changing the design. Specifically we:
1.Performed a comprehensive characterization of the AIR 30 blades to determine the optimal tip and root angle to capture the wind and made changes to the mold.
2. Optimized the software on all AIR products to enhance performance, reliability and reduce excess heat build-up in high wind speeds
3. Upgraded the circuit board using higher temperature rated components to further reduce susceptibility to extreme temperatures
4. Integrated changes to the circuit board configuration to reduce mechanical stress on the board and mitigate component failures

How do we know we did it right?

After completing improvements, we contracted an independent laboratory to perform a Highly Accelerated Life Testing (HALT). HALT uncovers issues in product design, component selection and/or manufacturing that we couldn’t otherwise find without running units in various field environments for an extended period of time. The HALT subjects the turbine to all kinds of stresses and weather and temperature fluctuations in quick succession.

AIR has been around for nearly 15 years and each year we discover new ways the product is used. AIR is found everywhere from a monitoring site in Antarctica to a village clinic in Sri Lanka. It’s the best because it is easy to install and operate. We at Southwest Windpower remain committed to making a difference with wind energy.

SWWP – Air X

Microprocessor-Based Technology

The AIR is by far the world’s number one selling small wind turbine.In late 2001 we introduced an entirely new level of technology which previously was only found in today’s state-of-the-art mega-watt-class wind turbines.

The Air X incorporates a new microprocessor-based technology that results in increased performance, improved battery charging capability, greater reliability and the reduction of “flutter” noise from the machine.

The controller allows for peak-power tracking of the wind by optimizing the alternator’s output on all points of the cubic curve and efficiently delivers the energy to the battery. The turbine’s smart controller allows it to actually control blade rotation speed thus eliminating the buzzing noise commonly found with most small wind turbines.

Quieter operation

Previous AIR wind modules relied on their aero-elastic blade design for protection in high winds. This caused a loud flutter noise in winds above 35 mph (16 m/s). Air X’s circuit monitors the wind speed and electronically slows the blades as it reaches its rated output preventing it from going into flutter. This results in a much quieter wind turbine. In high winds, the Air X will continue to produce power at a reduced level until the wind decreases, at which point maximum potential output will resume.

Improved Battery Charging

Previous AIR designs required 300-400 amp hour battery banks so the trickle charge of the wind turbine could be adequately absorbed. The Air X’s charge controller periodically stops charging, reads the battery voltage, compares it to the voltage setting and if the battery is charged, it completely shuts off all current going to the battery. This function is performed within a few milliseconds. The closer the battery is to reaching its full state of charge, the more often the Air X’s circuit repeats this action. This means any size battery bank from 25 to 25,000 amp hours or higher can be charged safely. When the battery has reached its charged state, the Air X will slow to an almost complete stop. Only when the battery has dropped below its voltage set point will it startup and resume charging.

Where and How Air X is Used

The Air X is an ideal product for the person that needs a little power for basic appliances such as TV, radio and a few lights.
Common applications for the Air X
Remote Cabins
Telecommunication Towers
The Developing World
Monitoring Stations


Unprecedented 3-YEAR WARRANTY
Carbon Fiber Composite Blades
Aircraft quality aluminum alloy castings
Exclusive Brush-less neodymium cubic curve alternator
Sophisticated internal battery charge regulator
Maintenance-free – Only two moving parts
Exclusive Auto-brake-feature that slows the Air X to a silent spin when the batteries are charged thus extending bearing life and reducing noise.


Product Brochure: Skystream 3.7Air X Brochure(333 KB)