The floating peakers


EDITORIAL The political fight over siting four city-owned power plants is heating up, and creating strange alliances. The San Francisco Public Utilities Commission wants to put three of the plants — which are small natural-gas-fired turbines — in the southeast part of the city, adjacent to the pollution-belching Mirant power plant at the foot of Potrero Hill. The commission argues that the city-owned plants would run only at peak hours (thus the term "peaker plants") and would generate lower carbon emissions and noxious fumes than Mirant does. Supporters of the plants argue that the state's Independent System Operator (Cal-ISO), which controls the electricity grid, won't allow Mirant to shut down unless the peakers are in place.

Sup. Aaron Peskin says the peakers will not only reduce emissions, but will give public power a kickstart. But Sup. Michela Alioto-Pier, who normally supports Mayor Gavin Newsom's plans, opposes the plants on environmental grounds, and Sups. Ross Mirkarimi and Chris Daly, who say the southeast has been a toxic dumping ground for years, appear to be siding with her. Add to this the cost of building a structure to house the turbines, which has varied from as high as $500 million to as low as about $250 million, and you have a confusing mess.

But as Amanda Witherell reports in this issue, there's another solution, one Mirkarimi floated several months ago: why not put the peakers on barges and site them offshore?

It's a fascinating idea. Floating power plants are common all over the world; Manhattan alone has more than 30. Putting the plants on a barge would, by some estimates, cost half as much as building a home for them on land — and they could be moved around so no one neighborhood has to suffer all the impacts. (The plants, for example, could spend some time in the Marina, maybe upwind of Mayor Newsom's house, so the southeast doesn't have to take all the emissions.) If the city follows its own plans and builds enough renewable energy to obviate the peakers in a few years, they could easily be shipped off and sold elsewhere. Or the city could lease them to other communities (bringing in some nice cash) when they aren't needed here. And floating plants won't face the serious seismic issues that plants on the unstable southern San Francisco shoreline do.

There are, of course, other issues with this, including the obvious problem of putting barges in the bay, which the Bay Conservation and Development Commission would probably object to. And where, exactly, would they go? This might not be the best idea in the end.

But given the lack of good options here, this is at least worth a second look. Mirkarimi needs to push his resolution calling on the city to review that option. It's well worth a full study. In fact, the board ought to put all final consideration of the combustion turbines on hold until the SFPUC looks at the barge proposal.