UC Researchers Conclude It Was A Mistake To End Hybrid HOV Privilege

On July 1, 85,000 hybrid vehicles in CA bearing clean-air stickers lost the privilege to drive solo in the carpool lane. UC Berkeley researchers show how that exclusion slowed speeds in the HOV lane while increasing congestion in the adjacent lanes.

1 minute read

October 12, 2011, 9:00 AM PDT

By Irvin Dawid


"When the regular lanes grew more crowded with hybrids, engineering Professor Michael Cassidy and doctoral student Kitae Jang said, carpoolers had to match the sluggish pace while moving in and out of their special lane.

In addition, Cassidy said in an interview, "You're not going to drive 70 mph in the carpool lane if the lane next to you is moving at 20. At any moment, someone can come into your lane."

However, the 'gap' of the 85,000 hybrids bearing yellow stickers may eventually be filled with paying single-occupant-vehicles if the Metropolitan Transportation Commission has its way. In addition, 'cleaner' vehicles than the hybrids may fill the gap due to 2010 legislation. This Air Resources Board webpage shows the three clean air stickers: Yellow is now expired after having been extended for six months, white was renewed last year until Jan 1, 2015, and green will be available on Jan 1, 2012, valid for three years.

Thanks to MTC Library

Tuesday, October 11, 2011 in San Francisco Chronicle

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

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