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Dirty little secrets about light rail and a clean environment

The Minnesota Sierra Club at a dinner Sunday will honor the “Override Six” – the Republicans who joined DFLers to override Gov.

The Minnesota Sierra Club at a dinner Sunday will honor the “Override Six” – the Republicans who joined DFLers to override Gov. Tim Pawlenty’s veto last session of $6.6 billion of tax increases (over 10 years) included in the transportation funding bill.

According to MinnPost writer Joe Kimball, club officials credit the six or giving the state “a stable source of funding to build the light rail lines and bus service needed to grow our economy and work towards reducing our global warming emissions.”

That would be well and good, were it necessarily true.

Cato Institute senior fellow Randal O’Toole in an institute Policy Analysis  “Does Rail Transit Save Energy or Reduce Greenhouse Gas Emissions?” answers that question with a “not necessarily so.”

“Far from protecting the environment, most rail transit lines use more energy per passenger mile, and many generate more greenhouse gasses, than the average passenger automobile,” writes O’Toole. “Rail transit provides no guarantee that a city will save energy or meet greenhouse gas targets.”

O’Toole’s statement would seem to fly in the face of common sense until one catches a blinding glimpse of the obvious – rail transit isn’t built in a vacuum. While most rail transit uses less energy than buses, for example, transit agencies supplement rail with extensive feeder bus operations. Individually, feeder lines tend to have low ridership, so they have high energy costs and greenhouse gas emissions per passenger mile.

“The result is that, when new rail transit lines open, the transit systems as a whole can end up consuming more energy, per passenger mile, than they did before,” O’Toole concludes, He adds, “In most cases, many decades of energy savings would be needed to repay the energy cost of construction.”

He notes that rail supporters have tied environmental improvements to rail’s ability to attract people out of their cars, which just hasn’t happened. O’Toole points out that technical solutions to environmental concerns about automobiles can do far more to reduce energy use and CO2 output than rail transit at far lower cost. His study shows that motivating 1 percent of commuters to switch to hybrid-electric cars will cost less and do more to save energy than getting 1 percent to switch to public transit.

Switching tracks
To justify tax increases, like the quarter-cent sales tax dedicated exclusively to transit (approved by five of the seven metro-area counties), light rail supporters have made a lot of claims about the benefits and savings of light rail, how it would attract people, reduce congestion and restore inner cities. Many of these claims have proved to be exaggerated wishful thinking.

For example, the progressive think tank Minnesota 2020 published a study (PDF) claiming, “Congestion costs the average Twin Cities rush-hour commuter $790 a year in wasted fuel and time. The average household would pay no more than one-third of that for Minnesota 2020’s transportation funding plan – $270 – and possibly much less.” The report also editorially commented, “Some antigovernment ideologues allege that public transit doesn’t reduce urban congestion.”

Well, anti-government ideologues may have first shed light on the congestion issue and the fact that taxes must be paid today for the promise of reduced congestion in the future, but now even rail supporters are coming out of the dark and are starting to see the light.

In an interview with the nonpartisan Civic Caucus,  Hennepin County Commissioner Peter McLaughlin said the chief objective of the rail system is to guide development. McLaughlin is chair of the Hennepin County Regional Rail Authority and chair of the newly created board that will distribute the transit sales tax funds.

Congestion relief is a lesser goal. In an article claiming that even “this conservative [Pawlenty] administration has warmed to the idea of transit as a force to reduce auto congestion, climate change and energy consumption,” MinnPost reporter Steve Berg later writes:

“Congestion relief should be discarded as a major emphasis. Prosperous, successful cities are congested cities. More stress should be placed on efficient development patterns, protecting the climate and environment and reducing energy costs.”

Berg’s comment was predictable according to O’Toole’s report. “One by one,” O’Toole writes, “all the original justifications for building light rail transit have been discredited by the evidence. In response, rail advocates and transit agencies offer two new reasons for building rail lines: energy and global warming.”

When subjected to data analysis, do those two new justifications for light rail fare any better than disingenuous projections for congestion relief?

What the evidence shows
Using government data and acknowledging the complexities of making apples-to-apple comparisons, O’Toole builds a table of Energy Consumption and CO2 emissions for various modes of transportation. Some interesting observations result:

In terms of passenger miles, light trucks and motor buses consume about the same amount of energy (measured in BTUs) and emit about the same amount of CO2. Light rail uses about a third less energy and emits about half the CO2 of buses and trucks; passenger cars use about the same amount of energy per passenger mile but emit about 50 percent more CO2 than light rail. The notable exceptions are hybrid vehicles like the Toyota Prius, which consumes, per passenger mile, less than half the energy required for light rail and emits a third less CO2.

This is where context becomes important if transit justification is to be based on energy consumption and CO2 emissions. Not only are passenger cars, according to O’Toole’s data, nearly as energy efficient as light rail on a passenger mile basis, but auto technology is becoming more efficient (e.g. the Toyota Prius) while transit’s efficiency is more or less stagnant over the life of a project 30-40 years.

“Projections of the energy efficiency of rail transit must take into account the growing efficiency of automobiles,” argues O’Toole. “A proposed light-rail line that promises to save energy not only needs to be more efficient than today’s autos, it must be more efficient than future autos. Since rail lines typically take 10 years to plan and construct, and have an operational life (before they need reconstruction and rehabilitation) of 30 to 40 years, they would have to be more efficient than the average auto 25 to 30 years from now to achieve any savings at all.”

Putting rail in context
“All of these numbers are very sensitive to load factors,” writes O’Toole. “Because the vehicles themselves tend to weigh far more than the passengers being carried, doubling the number of people on board any vehicle will cut energy consumption and emissions per passenger mile almost in half.”

O’Toole notes that increasing auto occupancies is “easier said than done.” Efforts to increase occupancies with carpool lanes have mostly failed. Transit is a different story, but one with a twist ending.

Transit loads are easier to manipulate by directing transit service to areas where demand is high and avoiding or providing smaller vehicles in areas where demand is low. Based on research on transit systems in major U.S. cities, O’Toole concludes that most transit agencies fail to do this for political reasons.

According to O’Toole, since transit agencies rely heavily on tax dollars, they try to provide at least some service to all taxpayers in the region. Because a large share of their capital costs are funded by federal grants, they also tend to buy buses that are larger than they really need. The result is that they often run buses that are nearly empty – which increases energy use and CO2 emissions based on passenger miles.

Because light rail lines are costly to build, when politically feasible, they are limited to major corridor routes, often displacing popular bus routes – the case with the Central Corridor line that will run between St. Paul and Minneapolis along University Avenue. 

Whereas buses can run frequent service in busy corridors and then diverge into various neighborhoods at the ends of the corridors, trains are confined to the rails. The result is that train cars are substantially empty at the ends of their corridors and during much of the day.

Another problem when light rail cannibalizes efficient bus routes occurs when the transit authority takes large-corridor buses and uses them on feeder routes to serve neighborhoods and bring people to light rail corridors. Because many people with cars drive to rail stations out of convenience, feeder buses operate with much smaller loads than the corridor buses they replaced.

“Many regions that build new rail transit lines end up using more fuel than before they built those lines,” O’Toole reports.

The Hiawatha Line is the exception that proves the rule. O’Toole notes that the Twin Cities transit system reduced both energy consumption and CO2 emissions following completion of the Hiawatha line. Two significant factors contributed to this result. First, the city of Minneapolis purchased several hybrid buses; second, no major bus route was replaced and there was no significant increase in feeder routes.

Of course, the trade-offs are a significant increase in capital costs for the hybrid buses and less-than-optimal service for people located away from the transit corridor.

Even rail lines that use significantly less energy than cars will not save much energy unless they attract a significant number of people who would otherwise drive their cars. O’Toole provides data that reveal no region with rail transit has been able to attract more than 0.5 percent of travelers to switch from cars to transit in the past 20 years. Transit’s share of travel has actually declined in 14 of 25 regions with rail transit. O’Toole concludes that even when systems report that their rail lines generate less greenhouse gases than automobiles, they are actually not saving energy if they are losing market share to automobiles.

Questions worth asking
Although it is certainly possible to argue with O’Toole’s data and conclusions, what is interesting about his study is that it raises logical questions, supported by data, that light-rail advocates simply choose to ignore.

For example, in addition to operational questions, light rail supporters fail to take into account the energy required to construct a light rail line. Even if a new light rail line could save energy and reduce green house gases, O’Toole argues, the energy costs and CO2 emissions from constructing rail lines are huge and may never be recovered by the savings.

“Highway construction also uses energy and emits CO2,” acknowledges O’Toole. “But each mile of urban highway typically carries far more passenger miles and freight ton miles of travel than a mile of rail transit line.”

The underlying argument O’Toole is making is for a cost/benefit analysis of transportation policy, rather than an emotional justification for “cool trains.” O’Toole concludes his analysis with suggestions for alternatives to rail transit that includes alternative transit fuels and technologies, increasing transit loads, making improvements to highways and streets, and improving automobile efficiencies.

“There may be places in the world where rail transit works,” O’Toole says. “There may be reasons to build it somewhere in the United States. But saving energy and reducing greenhouse gas emissions are not among those reasons. Regions and states that want to be green should find cost-effective alternatives.”