The Unknown Wind Turbine of San Francisco Bay or Angel Island State Park’s Enertech E44

By Paul Gipe

Yes, there’s a wind turbine in San Francisco Bay. It’s probably one of only two commercial wind turbines in all of Marin County.

Yes, it’s in a state park too.

It’s been there for more than three decades.

And there’s been no complaints, no howls of protests, no op-eds in the San Francisco Chronicle. No Manhattan Institute attacks on “derelict” wind turbines.

No one even knows it’s there despite the thousands of people who pass by it every day commuting from wealthy Marin County communities to their high-powered jobs in San Francisco’s office towers.

Is it hidden? Is it camouflaged?

No, it’s quite visible. Its three white blades stand out against the green of Angel Island State Park.

It’s visible from San Francisco’s Ferry Building. It’s visible from Nob Hill and Telegraph Hill. It’s probably visible from most anywhere along Fisherman’s Wharf.

It’s the mystery wind turbine of San Francisco Bay.

The wind turbine has been there at Point Blunt on the island’s south side, standing as a silent sentinel on San Francisco since I first arrived in the state in 1984. I think it was Second Wind’s Ken Cohn who first told me about it. Cohn was living on Lombard Street at the time—yes, that Lombard Street. He may even have pointed it out to me.

You might say I’ve been monitoring the wind turbine, an Enertech E44, for more than 30 years.

We were in San Francisco last week on vacation. I’d packed my camera to take some high-resolution images of the Windspire turbines on the new San Francisco Public Utilities Commission building that I’ve railed about as a classic case of greenwashing.

The weather was perfect for tourists: bright blue sky, little wind, and warm. We took the ferry to Larkspur to visit Nancy’s cousin Toni for lunch. The ferry passed right by the turbine—and I didn’t have my camera. I whipped out my smart phone and snapped a few shots. No one onboard even looked up.

It was still there when we returned. It hadn’t moved. It hasn’t moved in nearly three decades.

I resolved to get some photos of it when we took the ferry to Sausalito a few days later. I mentioned that I got some shots of a wind turbine on the ferry over to Toni, a resident of Marin’s Corte Madera when we arrived. She was surprised. “What wind turbine?”

That’s the reaction I always get: “What wind turbine?” I’ve been querying residents and tourists alike for years.

In October 2008, the online journal San Francisco Bay Crossings published an article titled Greening Angel Island State Park about efforts to reduce the park’s environmental footprint. The article noted that the wind turbine operated for five years before failing. During that time the turbine generated one-third of the island’s annual consumption.

The article quoted Joseph Wenisch, one of the founders of Eco-Island, who when sailing past noted that the turbine was never spinning. He asked his fellow sailors about the turbine and none even knew of its existence. Wenisch commented that “He wondered how it was possible that in arguably the most eco-aware city in the country, a wind turbine could be left in disrepair for so long. He thought of all the people that had seen the turbine broken . . . and how this may have ruined their image of wind energy.


The E44 was Enertech’s foray into commercial wind turbines during the early 1980s. The Vermont company had successfully marketed much smaller machines for several years, but the Great California Wind Rush enticed them to enter the commercial side of the business.

Small by today’s standards, it was big for its day. The E44 was typically installed on a 60-foot lattice tower. Its downwind 44-foot (13.5-meter) diameter rotor drove a 40-kW induction generator. (Later versions went as high as 60 kW.) At one time there were nearly 600 of the turbines operating in California alone. Unfortunately, the design had several strikes against it and it couldn’t really compete against the more rugged and reliable Danish wind turbines. The company eventually floundered. There have been numerous attempts to resurrect the design since the 1980s and one manufacturer in Nova Scotia may still be producing a modern version of the turbine.

I am posting some pictures of the turbine here in part for their historical value and in part to poke fun at Bay area environmentalists, especially those in Marin County, who are always read to attack wind energy when there’s a proposal near them. Yet they don’t realize they’ve been living with a wind turbine—derelict though it may be—for three decades and they don’t even know it’s there. Talk about being unaware of your local environment!

While San Francisco was quick to install small, unreliable, and unproductive wind turbines as so much architectural bling, the Bay Area has yet to install real working wind turbines in one of the world’s best wind resources.

Boston, on the other hand, has half a dozen commercial wind turbines within the city, in the harbor, or in nearby communities, such as Hall, Massachusetts. (One of Hull’s turbines is in a city park.) Boston’s turbines are visible from Logan International Airport and from flights into and out of the city.

Perhaps, those communities surrounding San Francisco Bay are considered more “eco-aware” only because they know how to generate better press than work-a-day Boston.

The accompanying photos were taken with a telephoto lens from the deck of a ferry from San Francisco to Sausalito.