It sounds like good news: some California legislators are trying to open up high-occupancy-vehicle (HOV) lanes to hybrid gas-electric automobiles, even if they have only one occupant. But—no surprises here—Ford is complaining, claiming that the move would only benefit Japanese-made cars such as the Honda Insight and Toyota Prius.

At first blush, the proposal to open up HOV lanes might seem like a reasonable idea: it could provide a slight incentive for people to purchase hybrids, which could help cut gasoline consumption, air pollution, and greenhouse gas emissions as well.

But on the other hand, hybrids don’t seem to need much help right now—the Prius is flying off the lots faster than Toyota can buld them. So in the short term, it’s not clear that opening up HOV lanes would do much, if anything, to boost hybrid sales.

  • But the bigger issue is, does it really make sense to open up HOV lanes to hybrids with a single occupant? Person for person, a car that gets 20 miles per gallon but carries 3 passengers is more fuel efficient than a Prius with a single driver. And, perhaps more importantly, clogging HOV lanes with SOV hybrids could slow down buses. In many cities, maintaining a smooth traffic flow for buses is one of the main benefits of the HOV lanes, since predictable times for bus travel can help raise ridership.

    And, looking slightly farther afield, adding hybrids to HOV lanes would actually open up more space for lower-mileage vehicles on the main highways. Each hybrid shunted into free-moving HOV lanes opens up a space for yet another car on the other lanes. (That, by the way, is an all-too-common problem with efforts to coax cars off the roads without reducing road capacity or internalizing the costs of driving: removing a car from the road frees up road space, and other drivers step in to take advantage of the reduced traffic.)

    So on balance, single-occupancy hybrids get a significant bonus *and* low mileage cars get a smaller benefit—but both, possibly, at the expense of the carpools and buses that already use the HOV lanes.

    Add to that, there’s the problem of precedent: once some SOVs are allowed in the HOV lanes, it’s much easier to widen the cracks by, for example, lowering the miles-per-gallon needed to qualify for the HOV lanes. Giving a free HOV pass to, say, a hybrid Ford Escape SUV that gets at most 36 miles per gallon is a bad tradeoff.

    I have little sympathy for Ford’s position on this—the federally funded Partnership for a New Generation of Vehicles gave U.S. automakers huge subsidies for developing hybrid technologies, but Japanese automakers still beat Ford to the market. Compaining about unfair advantages to foreign automakers is just crocodile tears.

    But I still can’t escape the feeling that, on this one, the pro-hybrid folks are wrong on the merits.