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Week Twenty-Six - Domestic Flights

Cut domestic flights by two-thirds to save 416 kilograms CO2e per person per year

· Weekly experiments

My kindergartner

- Last night my bed flew. It flew everywhere with me in it. It wasn't a dream, it was for real life!


- The world needs that tech. I'll write up your patent papers.

broken image

Flying shame

In Week Six I looked at international flights. There's an increasing environmental movement that shames those who fly and says we should all stay grounded. I'm always suspicious of green wisdom until I investigate because many tips that gain popularity have little impact. Some even backfire and increase your carbon footprint, like eating local and buying food without plastic packaging. But in this case, the green wisdom is right. Flying is the fastest way to fry the planet. Each year, overseas flights increase the average Australian footprint by around 1.1 tonnes of carbon dioxide and equivalent emissions (CO2e).

How much CO2e do domestic flights generate?

Australians fly domestically as well as internationally. How much CO2e do our local flights generate?

According to the Department of Infrastructure, Regional Development and Cities, Australians flew around 70.94 billion kilometres last year. Using standard industry emissions factors, those flights generated a total of 15.9 million tonnes CO2e or around 624 kilograms CO2e per person.

Prior to this project, I flew domestically a little less than the average. I travelled around twice a year, generating around 393 kilograms CO2e.

How did I cut back?

I used the same principles to cut back on domestic flight emissions as I used for international flight emissions. I found it much easier, probably because I love overseas holidays and loathe work travel.

I held one interstate work meeting in person and then arranged subsequent meetings via phone and Skype. This saved time as well as money and got the same outcome. My family caught the bus from Canberra to Sydney which took around the same as flying, because we didn't have to check in an hour early to the airport. We chose local driving holidays at the beach and the mountains. It was all pleasant, simple and cheap and it made our lives less hectic. I've come to question my instinct to jump on a plane to get away. Like many modern conveniences, plane travel promises convenience, freedom and relaxation but what it actually delivers is hassle. It makes us more busy, not less.

If you want to reduce emissions from domestic flights, fly less (or not at all). Stay for a longer time when you do go and make the most of it. Don't take frequent short trips. Teleconference for work and to keep up with distant relatives. Holiday locally. And fly economy, because those Business and First Class seats take up much more space on the plane and account for much higher emissions.

If you follow these principles, you should be able to reduce your domestic flight emissions by two-thirds.

A plane crash in the desert is a good reminder of why we should fly less

We're surrounded by sexy travel images. Before clicking Book Now, contemplate this. Still want to fly?

Online calculators

Google and the Government steered me towards the QANTAS online emissions calculator. It's a useful starting point but I didn't use it for my calculations. QANTAS rely on a much lower emissions factor than standard industry factors. After several emails back and forth, their data didn't convince me. Even the standard industry factors are an underestimate because they're tailpipe figures based on fuel use. They omit the embedded carbon in the jet which, given the amount of metal in the plane, would be significant. If you use an online calculator to work out the damage from your flight, consider doubling the airline's figure. Then add a bit. A bit more... that's about right.

Data dodging (or how we emit twice as much as we say we do)

As noted in Week Six, international flights aren't included in Australia's national carbon inventory. This means our whopping 21-tonne footprint is even higher. While not included in the official inventory, Australia does track international flight emissions. Just not very well.

The Department of the Environment and Energy told me emissions on international aviation led to around 12.5 million tonnes CO2e in 2016. I ran the numbers using federal government data and got over double their figure at 26.9 million tonnes CO2e. I asked the Department why our calculations differed? They explained that they look at aviation fuel purchased in Australia. They exclude fuel purchased overseas for the return trip or for extra hops on a multi-destination trip. They're counting less than half the trip.

Domestic flights are covered in Australia's 2016 National Inventory Report. Domestic aviation emissions are estimated at 8.944 million tonnes CO2e per year or around 370 kilograms CO2e per person per year. That's a lot less than my calculation of 624 kilograms CO2e. Unlike international flights, they are counting all the fuel. The Department tell me they use an emissions factor based on 'the makeup of the Australian aviation fleet including different aircraft types and their different emissions profiles'. I guess it's a lower factor than the set I'm using. We're up to our fifth round of emails and I can't yet understand the Department's view, so I'll stick with mine. All sources are set out in my 'Notes' section. Get in touch if I've got it wrong.

Spreadsheet calculations, data sources and references in 'Notes' section, Week Twenty-Six.

This revolting airplane meal shows the unglamorous side of flying

The glamour of airline travel doesn't last past the first meal (image courtesy of Flickr user thienzieyung).