Winnebago Via ready to roll. Image: Jenn Pentland
I have a confession to make. At the risk of provoking gasps of disapproval from the green gallery, I am declaring my love for The Road Trip. There is nothing quite like the exhilaration of the open road, despite what comes out of the tailpipe. Rolling down the interstate perched behind the wheel is at least as mesmerizing as staring into the campfire or sitting on the Pacific shore watching the waves crash.
Partially to feed my need for speed, but mostly to introduce our kids to new people, cities and landscapes, we (my wife and I) sold our house, jammed everything into storage, strapped the kids in and hit the road for an open-ended drive-about of the Western U.S. The rub being that we were attempting to be as green as possible while burning down the blacktop.
In our pre-children days my we did a similar trip with a mini-van and a tent. But, since I like my sanity, we decided that the ability to bring along the comforts of home to appease our almost-three and almost-six year-olds outweighed any inflation of our trip's carbon footprint.When Winnebago caught wind of our green family travel plans they offered up a 2011 Via motorcoach for the trip.
The Winnebago literature boasts a fuel efficiency rating of 15-18 miles per gallon, with the vehicle built on "a fuel-efficient Mercedes diesel chassis." My real-world calculations for 1200 miles of the trip came out to slightly less than that (see below). But, to be fair, I can easily see how higher numbers would be attainable if I eased up on the gas pedal a bit.
We spent just over a week in the Winnebago, but found that the layout of this specific unit wasn't working for us. Add to that our increasing concern about the indoor air quality of the coach (more on that in a future post) and it was time to swap it in for a different vehicle to get us through the rest of our trip.
I was hoping to get my hands on an hybrid of some sort, but Ford came on board with an offer to test drive a 2011 Edge. Although the hybrid version of the Edge hasn't yet emerged as hoped, the listed fuel economy of 27 mpg + necessary cargo space made for a good overall vehicle to do some practical comparisons. Quick, nimble and comfortable, we found the Ford to much more suited to our style of travel.
The Numbers - Fuel Economy
We drove just over 1200 miles in the Winnebago, burning through 90 gallons of gasoline at an average fuel economy of 13.63 mpg.
The Ford Edge carried us just over 2000 miles, using just over 90 gallons of fuel, averaging 21.8 mpg.
We also started and finished our trip in our VW Eurovan Weekender, traveling a total of 270 miles, on 18 gallons of fuel @ 15 mpg.
Looking only at fuel economy, the Ford Edge comes out way ahead, but there is more to the picture than just straight fuel consumption.
The Numbers - Carbon Impact
In order to get a fuller picture I turned to Mike Berners-Lee's book, How Bad Are Bananas: The Carbon Footprint of Everything. Berners-Lee sets out to give readers a "carbon instinct" in order to be able to judge roughly how much carbon dioxide equivalent (CO2e) a product or action produces. Luckily, he also stuffs the book full of real world numbers that he has calculated to illustrate his point.
Berners-Lee includes two measurements that help frame the carbon footprint of these different modes of travel. The first is a range of numbers measuring CO2e (carbon dioxide equivalent units) for driving one mile. The other range of numbers is emissions for staying one night in a hotel.
I went with Berners-Lee's fuel number because he includes the emissions from the extraction, refining, and transportation of the fuel, as well as the numbers from burning the fuel. His measurement for driving one mile ranges from about 3/4 of a pound CO2e for a Fiat 500 to 5.5 lbs for a speeding Mercedes Benz SUV. Inspired by his concept of a "carbon instinct" I set conservative numbers for the various vehicles.
I set the Ford Edge at 1.9 lbs CO2e emitted for each mile driven. This is Berner-Lee's number for an average U.S. car achieving 22.4 mpg. The Winnebago, I set at 3.5 lbs CO2e per mile, far less than Berner-Lee's high end but higher than the Ford because of the size and weight of the motor coach. I also assumed that our trusty, but aging, VW van emits 3 lbs CO2e per mile.
Comparing the extrapolated performance of the three vehicles over a 3500 mile round-trip would have the Ford Edge emitting just over 3 tons of CO2e, the Winnebago almost double at just over 6 tons and the VW spewing out about 5 1/4 tons of CO2e.
(Just for the record, our actual CO2e emissions for this trip, multiplying my estimated CO2e/mile for each vehicle multiplied by the actual miles driven in each vehicle comes to just short of 4.5 tons.)
The Impact of Accommodation
I had assumed that the CO2e numbers for hotel accommodation would shrink the gap between traveling by car and hotel vs. motor coach and camping. According to Berners-Lee a "high-carbon scenario", including extravagant dinners and over-the-top energy heavy luxuries, would equal 132 lbs. CO2e per night. Using this extreme number would add 2 tons of emissions for 30 nights in hotels. Luckily, we had the good fortune to stay in some green-certified hotels (stay tuned for this post as well) that would result in less than Berners-Lee's average emissions number of 53 lbs. CO2e/night.
Using my newly developed carbon instinct I would add another 3/4 of a ton CO2e for 30 days of semi-responsible accommodation if traveling by car.
The Bottom Line
The final number shake down like this:
2011 Winnebago Via + camping = emissions of approximately 6 tons CO2e.
2011 Ford Edge + hotels = emissions of approximately 3.75 tons CO2e.
1993 VW Eurovan + hotel/camping = emissions of approximately 5.75 tons CO2e.
Of course there are many other ways to travel. Biking and camping would reduce emissions to almost nil, while flying with stops in all of the major cities we visited and staying in a luxury hotel with a family of four would produce somewhere around 7 tons of CO2e. (Using Carbon Planet's calculator to determine the flight emissions.)
Calculating emissions numbers accurately is tricky. I had an assumption about how the different travel scenarios would stack up against each other before the trip, and after calculating everything, my assumptions turn out to be accurate. My only surprise is that flying doesn't produce more emissions. If you were to fly and stay in green-leaning accommodation there wouldn't be much emissions difference between that and traveling by Winnebago, or Eurovan.
Although I have a tough time accepting that it balances out the actual emissions we produced, the final step left in greening our family vacation is choosing a high quality offset to help atone for the five tons of carbon my family and I added to the atmosphere.