When OMRF last year announced plans to install 24 DNA-shaped turbines on the roof of its new research tower, the news sent ripples throughout the small wind power industry.
Once complete, the installation will make OMRF the first medical research facility to harness the wind to help power its labs. And with two dozen turbines, the project is believed to be the largest rooftop installation of wind turbines anywhere.
Now that the final beam has been placed on the shell of the structure, OMRF has begun the first phase of turbine testing and installation. This month, construction workers assembled a pair of the 19-foot-tall vertical-axis turbines on the roof in a shroud specially designed to house them.
“One of the reasons we chose these particular turbines is because they are designed to generate less noise and vibration than windmill-type turbines,” said Sheryl Rood, an engineer with the Benham Companies who is acting as a consultant on the project. “But before we went ahead with the entire installation, we wanted to test for ourselves.”
The OMRF turbines, manufactured by San Diego’s Helix Wind, are based on the Savonius rotor invented in the 1920s. “In turbulent air like what you’ll find on rooftops in cities, vertical-axis ‘urban turbines’ like OMRF’s have an advantage over traditional horizontal-axis machines,” said Rood. “Vertical-axis turbines don’t have to search for wind, because a portion of the machine is always facing into the breeze.”
For the last several weeks, Rood and a team of experts have been monitoring the turbines as they’ve spun free in the breeze. In particular, the team has been gauging the level of noise and vibration caused by the turbines.
“We need to ensure that the turbines don’t create any noise or vibration that will interfere with scientists and the experiments they are conducting,” said Rood.
The tower will also house thousands of genetically engineered mice, which researchers use to study the biology of disease. The animals can be extremely sensitive to even the most minor changes in their environment.
“Even small amounts of noise or vibration have been known to stop laboratory mice from eating or breeding,” said OMRF President Stephen Prescott, M.D. “Mice that refuse to eat or reproduce will bring a lot of research projects to a halt.”
So far, the turbines have performed well, Rood said. “We haven’t detected any significant noise or vibration.” Still, the winds have not reached sustained speeds of more than 20 miles per hour since installation. “We’re waiting for a really gusty Oklahoma day so that we can see what happens with 40-mile-per-hour winds.”
The turbines are marketed as being safe in winds up to 80 MPH and as able to handle gusts of up to 125 MPH. If they perform well at the higher wind speeds, OMRF will order another 24 machines: 22 to install and 2 for spare parts. The turbines are projected to generate about 58,000 kilowatt hours of electricity each year.
Along with other energy-saving features in the facility, the turbines are projected to help the tower cut electricity usage by as much as 37 percent. “Research facilities are typically energy hogs,” said Prescott. “But we’re doing everything we can to make this building a model of efficiency and sustainability.”
OMRF expects to complete installation of all 24 turbines by year’s end, with scientists and support staff to begin occupying the building in early 2011.