National Institute for Transportation and Communities

With its major cities clustered along 100 miles of the Willamette Valley, Oregon offers a fertile ground for electric vehicles and their limited range, George Beard of Portland State University said at a recent presentation. But Oregon’s readiness for electric vehicles doesn’t itself put one electric car on the road.

Beard, with Portland State’s Research & Strategic Partnerships, opened the Center for Transportation Studies’ spring Transportation Seminar Series with the presentation “Electric Vehicles: Are we in the Driver’s Seat?” It’s not just the population centers that make Oregon ripe for electric vehicles, Beard said. Automakers and governments have also invested heavily to deploy the technology in the state.

Oregon spends roughly $6 billion per year on gasoline, with nearly all of that money leaving the state, Beard said. Switching to a locally produced energy source could keep more of that money in the state.

Of course, predicting the future is never that simple, Beard said. Drivers unhappy with congestion won’t see that problem disappear because their cars now run on electricity. “Traffic congestion is a real killer,” he said.

“There’s no silver bullet that will solve our mobility problems,” he said. ”You’ve got to have a number of approaches for being able to move people and goods.”

For a technology that doesn’t require foreign oil, the fate of electric vehicles is intertwined with the oil cartels, Beard said. The...

OTREC researchers at Portland State University won the best paper award at the annual Transportation Research Forum for examining the effects of freeway traffic bottlenecks on costs. Graduate student Alex Bigazzi and Miguel Figliozzi, an associate professor of Civil and Environmental Engineering, submitted the paper for the forum, held in March in Long Beach, Calif.

Traffic flows can break down more or less at random as the freeway approaches its capacity. Although drivers pay a high price for bottlenecks both in their time and fuel costs, earlier models have taken an oversimplified look at how the uncertainty associated with how bottlenecks form, and how long they last, affect time and fuel costs. Without incorporating uncertainty, previous models underestimate the impact of congestion and bottlenecks.  The paper, called “A Model and Case Study of the Impacts of Stochastic Capacity on Freeway Traffic Flow Benefits and Costs,” takes into account the range and frequency with which these random or uncertain traffic breakdowns occur.  

Research detailed in the paper stemmed from an OTREC project, Value of Reliability. Figliozzi had considered the concept of reliability for years, even using it in his modeling class as an example on how to analyze the impact of uncertainty and combine diverse datasets and models—traffic, congestion, and emissions—into a cohesive model.

In terms of time and fuel...

In a tent in a parking lot under a freeway bridge, Ray LaHood saw the future of the country’s transportation network Tuesday. The U.S. Secretary of Transportation spoke to reporters, dignitaries and construction workers in the muddy work zone of Southwest Moody Avenue.

Last year, the project to rebuild Moody Avenue received a $23.2 million grant from the federal stimulus package. The project will double the streetcar tracks and add a cycle track and sidewalks. It will also ease connections to a new transit bridge that will carry the Portland-Milwaukie light rail line, the eastside streetcar loop, cyclists and pedestrians.

LaHood, joined by the area's congressional delegation, city and state officials, stressed the jobs the project is creating and the boost for the mix of transportation modes it represents. The project will also reduce congestion, LaHood said, by making transit attractive to current and future residents and employees.

Before construction started along Moody, automobile congestion was virtually nonexistent. However, it’s a heavily trafficked bicycle route connecting Portland’s cycle-friendly downtown bridges with its largest employer, Oregon Health and Science University.

By allowing choices of light-rail train, streetcar, bicycle and shoe leather, the project stands to boost those forms of transportation. If commuters leave their cars at home, that represents a reduction in congestion elsewhere. Of course, the project will also add...

It’s a common occurrence: a digital signboard over the freeway tells you to expect a 15-minute trip, but traffic clears and you arrive in 10 minutes. Or, worse, you hit a clog and arrive in 30 minutes.

Sometimes those signboards, called dynamic message signs, are way off, Portland State University researcher Kristin Tufte found. But sometimes that doesn’t matter.

Tufte examined the signboards, called dynamic message signs, along Portland-area freeways in an OTREC project. Drivers typically reach their destinations earlier or later than the signs told them to expect when a so-called “shock wave” forms or dissipates; that is, when traffic suddenly bunches or clears up.

Currently, only three of the 30 or so message signs in the Portland metro area display travel times. Detectors at freeway onramps feed those signs. As a result, large swaths of freeway without onramps also have no data. To be most useful, new message signs would require more detectors in certain areas.

Take the busy Marquam Bridge in Portland, where busy freeways merge and there is no signboard. “There’s no detection for the whole length of the bridge,” Tufte said. “If you really want to have accurate travel times, you have to have detection there.”

As expected, Tufte found that traffic bunching or clearing in blind zones can throw off the accuracy of travel times displayed. Surprisingly, that inaccurate information is...