It's no secret, we at TreeHugger are all for clean, renewable energy. Wind, solar, geothermal, wave, tidal, etc. But - and this is very important - it has to make sense. We won't automatically support any project just because it is clean power.
Unfortunately, that doesn't seem to be San Francisco Mayor Gavin Newsom's philosophy. In 2006, city officials announced that they wanted to build turbines under the Golden Gate bridge to capture energy from tidal currents. At the time, they expected up to 38 megawatts (enough for approx. 38,000 homes). But now a new study by URS, an engineering firm, is saying that there would actually be just 1 or 2 megawatts produced at a cost of many tens of millions with high yearly maintenance expenses. "Power generated from the tides would cost between 80 cents and $1.40 per kilowatt hour, according to the study." For comparison, the Bay of Fundy has about 300 megawatts of potential.Mayor Newsom has been recently quoted as saying: "I don't care about the arguments against it. I care about the arguments for it. I am going to find a way to make it happen." Granted, maybe he knows something that the public doesn't know, and if that is the case he should make that information available.
But if he doesn't have good reasons and wants to keep pushing just because it's a cool project, we ask him to reconsider... Come on, Mr. Newsom, that's taxpayer money we're talking about. There's an opportunity cost here. What matters is results. If a similar investment in another clean technology (solar, wind.. or even efficiency, which is too often overlooked) would yield better results, that's what has to be done first.
Wasting money on a white elephant would only give arguments to the anti-greens.
Maybe tidal power will come down in cost as the technology improves, and maybe at some later date it will make sense to harness the San Francisco bay currents, but right now unless someone can show that the URS study is flawed, it doesn't seem to make sense.