Green Airlines? Or Just Full Flights?

There is a great deal of advice out there on how to make green purchases, guiding consumers through a maze of information.  In each category, the green product has a special feature or features.  Consider these examples:

  • Green clothing – Contains more earth-friendly content, such as bamboo fibers
  • Green detergent – Releases fewer toxins, such as biodegradable detergent
  • Green appliances – Uses less energy and water, such as a front-loading washing machine

Does the same method work for airline travel?  Decidedly not.

Airlines buy from only a few manufacturers, so airplane technology is fairly standard across all airlines.  Fuel is the airlines’ biggest expense after labor, so airlines have every incentive to reduce energy use.

So how can one airline be greener than another?  Does one really use less fuel or emit less carbon?   The answer is in the data.

The airline industry measures everything PER SEAT.  Take a look:

  • Available seat-miles  [# seats x # miles flown]
  • Load factor [# seats sold/seats available]
  • Revenue per seat-mile [$/(seats x miles)]

As such, it might seem natural to measure fuel use per seat-mile and carbon emissions per seat-mile too.

With this method, longer flights and larger planes come out “greener,” because they use less fuel per seat-mile.  An airplane flying from LAX to Sydney would be green, but not so with one flying from LAX to Las Vegas.  But is the former really greener? Or is this, in fact,  an apples-to-oranges comparison?

Let’s go one step further.  Typically, data on airline emissions are directed toward an individual consumer, so the emissions for all flights flown in a given year are divided amongst all the passengers and miles flown to create a metric: carbon emissions per passenger mile.  The emissions are an industry average.

But when this calculation is done for each individual airline, the results can become pretty skewed.  For example, compare two flights from LAX to Las Vegas, one very full with passengers and one very empty.  The full flight will be the “greener” one, as fuel use per passenger will be lower.

Recently, Brighter Planet—a San Francisco-based company that specializes in carbon calculations—issued a report ranking airlines from the greenest down to the least green.  Its results illustrate all the problems detailed above.  In other words, a large plane flying a long route with every seat filled is “green.”  Would you choose this product?

Brighter Planet goes on to make recommendations for corporate travel programs, suggesting that emissions can be reduced by selecting the greener airline serving the route.  But, here it confuses the airline’s average with the route specifics.  Airline “X” may fly most of its flights from LAX to Sydney and only one or two flights from LAX to Las Vegas.  However, that does not make it a greener airline on its LAX to Las Vegas route.

As a consumer, it’s your choice.  The best choice you can make for emissions is to stay home.  Don’t drive or fly; just telecommute.

And if you fly and want to be “green”, call the airlines and shop around for the fullest flight.  Your share of the flight’s fuel will be the lowest possible. Get ready for no legroom, and don’t forget to bring along your earplugs.


WattzOn Labs is always innovating ways to engage people to save water and energy. It showcases the WattzOn products under the WattzOn Labs private-label. We don’t market these products, but use this small-scale direct-to-consumer experience to constantly evolve and learn. Then we apply the findings to the rich, private-label products used by all our customers at WattzOn.