Just how Green is Public Transportation?

Which is more wasteful: your car or the city bus?

Where I live, the South Bend public transportation system ferries individuals around the city. It's not a bad deal – for those who ride it. You can buy a ticket anywhere on the route for 75 cents, and a month pass is only $30. It sure beats owning and fueling a car!

But, as environmentalists are so keen on pointing out, things that appear cheap often have hidden costs. How can the bus afford to charge such low fares? At first you might think that it’s because carrying a lot of passengers in one vehicle is more efficient than individuals driving their own vehicles. That's true with carpools, since the gas mileage is virtually the same even if you double or triple the number of passengers. But for a long time, in spite of its image as a more “socially responsible” means of travel, public transit has been among the least efficient ways to get around when it comes to energy consumption per passenger [1].

Energy consumed means fuel burned. Buses have low fuel efficiency, and ridership is almost always anemic because public transit is slow, poorly documented, unpredictable, and available only in a handful of situations. As one University of Wisconsin science professor points out, the bus is actually quite costly when factoring in your time and the safety risks [2]. When your time is valuable, it stops being economical to ride the bus, because most feel their time is better spent with family and friends than on riding mass transit.

But I want to look specifically at the public transit system near me, as an example of just how inefficient - just in terms of cost per passenger mile – this mode of travel is. (A passenger mile is defined as one passenger going one mile. If you drive 10 miles alone, you have gone 10 passenger miles. If there are two of you in the car, the car has covered 20 passenger miles.) In 2006, the South Bend Public Transportation Corporation (TRANSPO) spent a grand total of $9,935,372 – just under $10 million. About $800,000 of that was in “capital funds,” meaning money invested in new infrastructure and equipment. The rest went for operating expenses.

Income from bus fares consisted of $1,364,853. Obviously this number falls far short of the nearly $10 million that the South Bend Public Transportation Corporation spent that year. Where did that money come from? Advertising revenue? Gifts from some wealthy benefactor? Tips? Far from it. Public transit, especially in smaller cities like South Bend, is highly subsidized. Local, state and federal taxes covered a whopping 80 percent of operating expenses in 2006, the most recent year with published financial data [3]. Those bus fares covered only 15 percent – and those are just the operating expenses. The breakdown of income for TRANSPO looks like this:

• Local Funds: 47%
• State Funds: 23%
• Fares: 15%
• Federal Aid: 10%
• Other: 5%

These numbers don't take into account the capital expenditures, or money spent on new infrastructure, an additional $800,000 that appears separately on the financial report. That money was provided almost entirely by the federal government.

I guess we can give them a little credit for the bus fares being in the middle of the pack instead of dead last. I can't speculate on where “Other” came from, but this chart leaves 80 cents of every dollar spent on running the South Bend bus system coming from a taxpayer's pocket.

The situation we have here is one where people not riding the bus have been drafted to pay the vast majority of the fare.

But let's set aside for a second the issue of whether or not it's fair to charge those who don’t ride the bus so that others can get a better deal. Let's look at the bus system itself. In my research, I found that it is rare – if it ever does occur – for public transportation to be better on the environment than personal vehicles. One of the articles at Templetons.com, the website of Brad Templeton, founder of ClariNet and chairman of the Electronic Frontier Foundation, provides a chart of BTUs per passenger mile, all based on the government's numbers. The San Jose (California) Light Rail is the absolute worst, burning up an astronomical 7,000 BTUs per passenger mile. [1]San Jose Light Rail: Burns an astronomical 7,000 BTUs per passenger mile.

A car with one occupant is still not very green, taking about 5,500 BTUs to take one person one mile. But the San Jose Light Rail is an extreme example of what happens with public transportation. In the case of the light rail, all that energy is spent hauling all the tonnage of a train back and forth, while the occupancy of the train is small at best. The efficiency of the car, on the other hand, effectively doubles the moment you add a passenger. According to the numbers which Brad Templeton gathered from the Department of Energy, a car with an average of 1.57 passengers is right in the middle of the chart as far as energy efficiency goes. It takes less energy than the city bus and less than a trolley.

Energy efficiency based on passenger miles is integral to the cost of transportation. In every case, the main recurring expense in all modes of transportation comes down to one question: how much does it cost to make the thing move? I ran the numbers for the South Bend public bus system and discovered that based on the passenger miles traveled and the total money spent by TRANSPO, the cost of the bus is 74 cents per passenger mile. And that's ONLY if we cover the operating expenses. Throw in the “capital expenses,” which basically means federal money spent on expansions, and the cost comes to 81 cents per passenger mile.

To put this in perspective, the American Automobile Association says the average cost per mile of owning and driving a car is 56 cents. Your mileage may vary, but in my case, with a small car that I own outright, with reasonably priced insurance and even at $4.20-a-gallon gas, it costs less than 35 cents per mile for me, and that number goes way down, below 20 cents, the farther I drive. Since the vast majority of the driving is commuting with the wife, I have to divide by two to get the cost per passenger mile and end up with less than 18 cents, at the most.

But guess what? Based on the 2006 data, thanks to all those subsidies, riding the bus costs the passenger only 11 cents per mile! I'm within easy walking distance from a bus stop, and that bus goes to or gets near all the places in town I would really care to go to, including to work, so why don't I use it?

This is where we get to the economics of mass transit that lots of people never even think about: the value of your time.

I could sit around and wait for the bus, take a long and winding route to my destination in a vehicle with people I don't trust, and have my itinerary restricted by the bus schedule. But my time is worth something. I get paid time and a half for overtime because time with my wife, while away from work, is at least that valuable to me. Extra time waiting to get on the bus and the lengthier ride all add up quickly to a cost in time which I'm not willing to pay, even if I save a few cents a mile by not driving. Worse still, mass transit gets more expensive when you add passengers, not less. If I brought my wife, it would cost 22 cents a mile for us to get around on the bus. At this point it's no different in cost from just driving downtown, and driving puts our time in our own hands. Conversely, adding a passenger to a car increases its cost effectiveness, since the vast majority of the energy you buy is spent on moving that car around – the human bodies are negligible by comparison. A car quadruples its efficiency per passenger mile if you just add three passengers.

Moreover, since the vast majority of us are going to own cars anyway, why pay the recurring costs of the car, such as insurance and maintenance, plus the price of bus fare? I can reduce the monthly cost per mile by driving more, since fuel is about 14 cents per mile and costs like insurance are fixed monthly amounts. My cost per mile of owning the car actually goes UP the more I ride the bus.

It may sound as if I'm over-defending the automobile here, but I'm not, even though it probably deserves defending, with all the assaults on it from environmentalists. Frankly, I marvel at governments' propensity for building roads, and I wonder how transportation would have evolved without a government monopoly on them. The conclusion I'm really getting at is that there's a reason public transportation needs so much subsidy to stay afloat: it's not economical! It's not energy efficient and it's not, in general, what people want or need. Otherwise there wouldn't be so many empty buses trundling around town. Even with subsidies making them cheaper, people don't ride them because, consciously or unconsciously, they decide that the pros are outweighed by the cons.

The real future for greener travel is in better personal vehicles. Electric cars, cleverly built hybrids, smaller commuter cars – the possibilities are numerous. Private vehicles don't require the administrative overhead that pads the costs of so many public transportation systems. They are used only when needed, unlike public mass transit, which navigates its route with or without passengers.

But what, say the defenders of public transportation, about traffic congestion caused by so many people driving? What about all the idling engines spewing fumes into the atmosphere? To this I have only the following to say: If congestion were such a problem, people would seek out alternatives to driving. As it is, driving remains the preferred way to get around. The only way you can get these people out of their cars is to offer them something better, and so far the consensus among commuters is that a bus, train or subway is not better. If they were, those commuters who abhor the rush-hour traffic would choose them rather than drive.

The effects of congestion will go down as more people buy vehicles with greater fuel economy, such as hybrids, which typically switch to all-electric mode when stopped or moving at very low speeds. With enough of these on the road, traffic jams could turn into zero-emissions events.

City government officials opt to institute a public transportation system because they believe it can cut down congestion and that it must be a less smog-inducing means of travel. Unfortunately, mass transit does little to correct either of those problems, while draining the taxpayers. Such transportation has a role, but buses, trains and subways do not deserve the green halos so often awarded them. Since “green” typically means the use of less energy, it will frequently also mean greater efficiency and a lower price. This alone will tend to steer people to make the right decisions, with or without “green” marketing to tell them what's good for Mother Earth.

The sad truth is that mass transit is frequently cursed with negative effects on energy conservation, because people don't use it. People don't use it because it doesn't match their needs. The answer is not to compel people to change their needs, through taxation and legislation. The answer is to find something that DOES serve their needs. Since the government monopoly has seen fit to give us an infrastructure that greatly favors individual vehicles, then for now the best way to reduce environmental impact quickly is innovation in the personal vehicle. Perhaps instead of taking the bus, take up cycling or invest in a moped for short trips. If possible, trading your car for a more efficient one that you can own debt-free will save you thousands. Don't assume that all "green" marketing is accurate. Your wallet will thank you.

[1] - http://www.templetons.com/brad/transit-myth.html
[2] - http://www.uwgb.edu/dutchs/pseudosc/masstransit.htm
[3] - http://www.ntdprogram.gov/ntdprogram/pubs/profiles/2006/agency_profiles/5052.pdf