Alex Goldmark is the senior producer of New Tech City, a storytelling show about how technology is changing society. Subscribe here to get New Tech City shows delivered right to your devices. Follow him on Twitter @alexgoldmark.
Three Fast Facts on the Carbon Benefits of Transit
Monday, April 22, 2013 - 06:23 PM
Among the Earth Day offerings for those looking to show support for Mother Earth there was: recycling old batteries in a three story tall recycling bin, or browsing guilt-assuaging consumer products made from pulped magazine paper, bamboo shoots or raw moral righteousness. There's also the more mundane act of riding transit.
Here are some stats that crossed the Transportation Nation email inbox this earth day.
Each transit trip saves 10 pounds of greenhouse gases.
According to the American Public Transportation Association, transit use in the United States saves 4.7 billion gallons of gasoline annually, which adds up to 37 million metric tons of yearly carbon emissions savings compared to everyone driving their own cars. The biggest transit agency in the country, the New York Metropolitan Transportation Authority, calculates "that its operations reduced the carbon dioxide and other greenhouse gas emissions of the region by 17.1 million metric tons in 2011." Calculated on a per trip basis, that's how you get the 10 pounds of carbon savings per trip, compared to private car trips.
The intercity bus: 14 times less pollution than driving.
Consider the choice of driving between cities or taking a bus. Intercity buses are on the rise, up about 30 percent in 2012 according to one study from DePaul University, a trend that Earth Day observers might celebrate. Take Megabus, with its double-decker blue motorcoaches. Each of those blue behemoths remove roughly 30 or 40 cars off the road, depending on how full it is.
Here's the math for that: Each bus fits 77 passengers. Cars, on average, have 1.55 people in them according to the U.S. DOT. Now, the bus uses more gas per mile than a car, but not more gas per passenger, and that's what matters. Megabus estimates it uses .002 gallons of gas per passenger per mile on a full bus. Cars use about .027 gallons per passenger per mile. (There are many figures for this; we used the 23.49 miles per gall0n avg per car from DOE, dividing by the 1.55 passengers per car of U.S. DOT). So riding Megabus is roughly 14 times more fuel efficient than driving.
Note: not all buses attain carbon glory. City transit buses are not very fuel efficient, mainly because there's not many people riding them at any given time. The U.S. Department of Energy places transit buses below personal cars because it figures average ridership rates have them just 25 percent full on average. That said, see next bullet.
A third of public city buses are hybrids or alternate fuel vehicles.
The American Public Transit Association found that 35 percent of public transit buses in the U.S. are either hybrids or use less polluting alternate fuels, like clean natural gas. Only 1.3 percent of private automobiles can say the same.
From APTA: "18.6 percent of U.S. transit buses used compressed natural gas, liquefied natural gas and blends. Almost 9 percent of public transit buses were hybrids and nearly 8 percent of public transit buses used biodiesel."
Kids are cute and they like transit
This isn't a quick fact, it's just a cute video about carbon savings and transit.
You can calculate your commute's carbon impact here.