Scores of windmills, which for millennia have provided a familiar backdrop to agrarian life, are poised to blow into San Francisco’s urban core on the winds of technological and bureaucratic change.
Wind power is considered a renewable energy source, like solar. A wind turbine can look like a giant fan — simply put, the wind turns the blades, spinning a shaft connected to a generator to make electricity. Nationwide, the number of small, electricity-producing wind turbines grew from several thousand earlier this decade to more than 35,000 in 2007, according to the American Wind Energy Association.
In San Francisco, four wind-energy companies have set up shop; in April, Mayor Gavin Newsom announced the formation of a task force dedicated to looking at The City’s potential to pursue and encourage wind power. To date, six turbines have been installed in San Francisco, three on private homes.
Earlier this month, Newsom eliminated one of The City’s biggest barriers to residential wind energy by sending out directives asking planning and building-inspection departments to “expedite permitting and minimize costs” needed to install residential, commercial and municipal wind turbines in The City.
Prospective wind harvesters have been hamstrung by the lack of a standard turbine-permit application process, said San Francisco builder Robin Wilson, a task force member who last year founded Whirligig Inc., which sells and installs turbines.
Until now, San Francisco has been able to take only small steps on the path to wind power, those paved by city supervisors who have supported individual wind projects in their districts. Supervisor Tom Ammiano, a task-force member, tweaked height rules to help Todd Pelman, founder of the San Francisco start-up Blue Green Pacific, install a turbine on his Bernal Heights home. Board colleague Bevan Dufty also helped secure a permit for a residential turbine on a home in the Castro.
In addition to encouraging wind-power technology for residents and businesses, Newsom also ordered city departments to incorporate wind turbines into city facilities “whenever and wherever possible” in his July 17 directives.
There are currently no wind turbines operating on municipal buildings or city-owned land, however, and a study revealed the challenges San Francisco faces if it wants to create a large-scale wind-energy project.
Commissioned by The City in 2004, the study discovered “poor” economic feasibility for wind-energy projects at Pier 39, the San Francisco Zoo and Hunters Point — all waterfront locations. Treasure Island and the airport were found to harbor wind-energy potential, while Twin Peaks was the most promising site studied.
There is massive variation in the amount of wind energy that can be captured in San Francisco, which is dominated by microclimates and wind-tunneling buildings and streets.
“If you’re really interested in doing wind at your site,” suggested The City’s Environment Department Renewable Energy Program Manager Johanna Partin, “you should really put up a wind data-collection device for six months.”
The City is considering subsidizing the prices of so-called wind anemometers, which retail for $150, or renting them out to residents to help defray the costs of the measurement devices, Partin said.
On a larger scale, Partin said the new urban wind-power task force will also investigate The City’s options to build an offshore wind farm, similar to one recently approved in Massachusetts. In that project, 130 planned open-water turbines will produce 420 megawatts of electricity — more power than is produced by The City’s only remaining power plant at Potrero Hill.
Ahead of the game
There are currently six wind-energy turbines in San Francisco.
- 45-foot vertical-axis windmill on a Mission neighborhood home
- Pair of 6-foot 22-inch-wide horizontally-rotating turbines on a Castro garage
- Similar 7-foot turbine on a Bernal Heights rooftop
- Vertical-axis windmill at the Randall Museum
- Pilot turbine on Treasure Island
Source: San Francisco Environment Department
By the numbers
34: Members of a city-sponsored urban wind-power task force, announced in April
6: Wind turbines in The City
0: City-owned wind turbines
4: San Francisco firms developing or selling wind turbines
9: Bay Area firms developing or selling wind turbines
8.2 mph: Average wind speed 33 feet above Pier 39
12.7 mph: Average wind speed 33 feet above Twin Peaks
Sources: San Francisco Environment Department, San Francisco Planning and Urban Research Association