Why has Arizona State University installed six parapet wind turbines on the roof of the recently remodeled Global Institute of Sustainability building?

Wind turbines generate electricity from a free and clean renewable resource. They don't add to global warming. And unlike solar power, the wind is often available both day and night.

The six turbines at the Global Institute of Sustainability have been in operation since mid-October. They are all mounted on the east façade of the building — easterly is the prevailing average annual wind reported at Sky Harbor International Airport . But the turbines can be driven by wind from almost any direction, even thermal updrafts created by daily temperature fluctuations.

The turbines function across a range of wind speeds. Wind speeds of 27 mph or higher allow the turbines to generate maximum power, yet they can also produce electricity with winds down to five miles per hour. This flexibility is important because the average wind speed in the Phoenix area clocks about seven miles per hour annually.  Under average conditions, the six turbines produce enough electricity to power about 36 computers, thereby reducing ASU's reliance on non-renewable energy sources by that amount.

More impressive than the power the turbines generate, however, is the discussions they stimulate. From their prominent rooftop location, the iconic turbines are visible from Cady Mall and University Drive where students, alumni, parents, and visitors from across the country and around the globe have a chance to see and think about them.

"The real value of the turbines comes when they prompt a student to say ‘I should study wind power,' or an alumnus to think ‘My company could convert to renewable energy,'" said Jonathan Fink, the Julie Ann Wrigley Director of the Global Institute of Sustainability and University Sustainability Officer. The Institute is the hub of all of ASU's sustainability efforts, advancing research and education, integrating sustainable practices into University operations, and modeling sustainable alternatives at every opportunity.

While the wind turbines are eye-catching and functional, they are only one ASU strategy for generating electricity from a renewable resource. The university is also overseeing one of the largest campus-based photovoltaic installations in the United States, with long term plans to reach 7 megawatts of roof-top solar generating capacity. Both wind and solar power will help ASU reduce its carbon footprint while also stimulating expanded interest in alternative energy solutions.