Green ways to travel

green-travel-vagawi-flicker
Photo courtesy of Saw You On The Flipside

For some people, travel is an unpleasant necessity. They travel to meet clients or commute. For other people, travel is a joy and the reason that they work. They save up money for vacations and sight seeing. Whether you’re in a hurry to get home or if you’re taking the chance to satisfy your wanderlust, there are plenty of opportunities to add some green to your itinerary.

From hiking boots to luxury jets, we have more transportation options today than ever before. Most travelers weigh these options based on comfort, price, and time. Yet an increasing number of adventurers and businesswomen are factoring in the environmental impact before they buy tickets.

When choosing transportation with a small carbon footprint, it’s important to compare apples to apples. One way to compare the environmental impact is using passenger miles. Passenger miles are calculated by taking the total fuel consumed and dividing by the number of passengers. For example, consider a car that gets 40 miles per gallon. If the driver is the only person in the car, then the driver is responsible for 19.4 pounds of CO2 for every 40 miles driven or 0.485 pounds per mile (19.4 / 40).

If we add a passenger with heavy bags, the car’s MPG will decrease slightly to about 39 MPG, but the amount of carbon dioxide generated will stay roughly the same. That footprint is spread out over 2 people instead of one. (19.4 / 2) / 39 = 0.249 pounds per mile. This is because so much of the energy used in moving a car is used to move the car itself.

In short, vehicles that travel full are more fuel efficient than empty vehicles, and passenger load can greatly affect the pollution produced per person. While trains are often more carbon efficient than buses, a fully loaded passenger bus may even be more efficient than a train. Then again, rail systems in some countries have the edge.

The most common way to compare different fuel sources is to use Miles Per Gallon equivalence (MPGe), but some fuel sources are dirtier than others. For example, generating 100,000 British Thermal Units (BTU) from coal will produce about 42 lbs of CO2, while natural gas will produce the same amount of energy while emitting about 14 lbs of CO2. So, a coal powered train may be more energy efficient than a natural gas powered bus, but it would produce more pollution to travel the same distance. Hard numbers for this “pollution efficiency” are difficult to pin down.

And that’s not all… some situations can magnify the effect of emissions. For example, pollution from airplanes is released in the upper atmosphere. Carbon dioxide, nitrogen oxide, water vapor and other byproducts behave differently in the upper atmosphere than they do at ground level, multiplying their effects. For more information on this subject, look at how various scientists calculate the radiative forcing factor. As a rule of thumb, each pound of airplane emissions is about 2.8 times worse than emissions from other forms of transportation.

From lowest impact to highest impact, here is a rough guide to transportation options (including some data from the US Department of Energy Transportation Energy Data Book and manufacturer’s sites):

On foot / Walking
Bicycle
Horseback Riding
Rickshaw
Electric Motorcycle / Scooter
Vanpool or Shuttle (1,322 BTU per passenger mile)
Motorcycle (1,855 BTU per passenger mile)
Train (2,816 BTU per passenger mile)
Ultra Efficient Passenger Car (ie; a Prius)
Average Passenger Car (3,512 BTU per passenger mile)
Passenger Trucks/SUVs (3,944 BTU per passenger mile)
Bus (4,235 BTU per passenger mile)
Turboprop Passenger Plane (for short distances)
Fuel Efficient Passenger Jet (for long distances)
Piston Engine Passenger Plane
Older Passenger Jets
Small Prop Plane (ie; Van’s Aircraft’s RV-7: ~36 MPGe per passenger at full capacity)
Ferryboat
Helicopter (~20 MPGe per passenger at full capacity)
Cruise Ship (~17 MPGe per passenger at full capacity)
Motorboat (~15 MPGe per passenger at full capacity)
Jet Ski (~10 MPGe per passenger at full capacity)
Executive Jet (~0.8-5 MPGe per passenger at full capacity)

Are there any transportation methods that I’m missing? It’s hard to quantify the MPGe for a hang glider, sailboat, submarine, electric pogo stick, or jet pack, but if you have the scoop on how to rank an unusual form of locomotion, please drop a note in the comments at the bottom of this page.

So, how can you use this list? Before you book a trip or reserve a hotel room, make sure to check out all of the options that are available. Instead of flying cross country, do you have time to take the train? Instead of staying at a hotel across town from a conference, can you find a hotel within walking distance and skip the rental car?

A few more tips for carbon efficient travel…

  • Maximize the capacity of your vehicle: carpool, combine taxis, choose a party boat instead of a dozen jetskis
  • Travel light: ditch 2 suitcases and you may be able to fit another passenger in your car or cut your weight in half on an airplane
  • Choose direct flights: up to 80% of a plane’s fuel consumption happens during take-off and landing, flying direct also cuts out unnecessary miles in the air and, as a bonus, can reduce the amount of tax and airport fees charged
  • Pick fuel efficient cars, planes, and motorcycles: newer vehicles are often much more fuel efficient (ie: the 737-800 airplane gets about 35 percent better mileage per seat than the MD-80 it is replacing).
  • Make the captain a passenger: get certified to operate your own riverboat, learn to fly your own plane, or (if you have one) ditch the chauffeur back at the mansion
  • Often, the green choice will yield a more pleasant trip and save money at the same time!

    green-travel-svanes-flicker
    Photo courtesy of svanes

    Beat high gas prices – ride the bus or train!


    Photo courtesy of
    George Morris at Flickr.com.

    I recently rode an Amtrak train from Chicago to Dallas, and every seat was full. Compared to my previous experiences on Amtrak, that was an amazing change. Just 6 months ago, I remember that there were 4 empty seats for every one that was claimed. When I asked my fellow passengers why they chose to ride, the hot topic was the high price of gas. Fuel prices are driving up the price of airplane tickets (just last weekend, fares rose $20!), and 3 major airlines died in the first quarter due to oil shock. Drivers are also becoming aware of every drop of fuel that they use – no one likes to see a $50 or $100 charge at the pump!

    The silver lining of this is that we’re starting to see the cost of different modes of travel mirror their real price in terms of pollution. High gas prices are making environmentally friendly transport more and more competitive. In effect, this is a preview of how a carbon tax could change the face of travel.

    Train and bus ridership are growing like crazy:

    As gas price keep climbing, a growing number of Americans are leaving their cars in the garage and getting on board trains. Commuter train lines around the country are reporting big jumps in first quarter ridership: up 15% in the suburbs of Seattle, 13% in the communities north of Miami, 7% in the region surrounding Minneapolis-St. Paul, and better than 5% in New Jersey.

    Subways and bus routes are feeling the boost too. People are leaving their cars at home and hopping on public transport. Unfortunately, since many of these commuter services use petroleum based fuel, their costs are rising too. Increased ridership can offset these increased costs in the short term though. It costs almost as much to run an empty train as it does to run a train with 40 people in it. Additional paying passengers add minimal costs while bringing in much needed revenue. Fuel prices are also rising for train and bus operators though. When commuter services charge the same despite rising prices, this can eliminate any efficiency gains.

    If the price of oil stays at these levels, there’s likely to be widespread demand for better public transportation:

    Five dollar gasoline may be enough to force some people to give up steady use of their personal cars and seek other solutions. For others, the quitting price may be ten or twenty dollars per gallon and for the very wealthy even $100 a gallon gasoline ($80 or $100 thousand a year) would be an acceptable price to pay for the convenience of the private car.

    In the case of slowly increasing gasoline prices the problem is one of forming a critical mass that will make economic sense for greatly expanded mass transit. Such a critical mass is likely to come for long distance travel first, for as soon as discretionary air travel becomes unaffordable, the demand for better train and bus service will increase rapidly. Long distance automobile travel may fill some of this gap especially for moving multiple passengers or if cars become significantly more efficient, but for the lone traveler, a long distance car trip could become very expensive.

    If you’re undecided about taking the train, here are 9 underappreciated benefits of train travel. Compared to travel by air, the benefits of train travel boil down to lower cost, increased comfort, and reduced hassle from security. Air travel still wins on convenience, reliability, and prestige. Long distance buses are also a great option – some studies suggest that intercity buses the most fuel efficient travel available today:

    Based on mileage and passengers in 2004, highway buses achieved an average of 148.4 passenger miles per gallon. That’s more than double achieved by intercity trains which achieved 74.1 passenger miles per gallon. Airlines managed 40.9 passenger miles per gallon, while cars came in last at 35.4 mpg.


    Photo courtesy of
    VSPA at Flickr.com.