How to make flying more eco-friendly, if you really have to fly

Even if you’re doing your best to avoid flying, chances are that most of us are going to end up on a plane at some point. It’s become so ingrained in our lifestyles in developed countries (and now in some developing countries) that it’s hard to completely avoid flying, especially when relationships and other demands press us to travel long distances.

We quit flying nearly seven years ago now, but we haven’t managed to completely avoid flying since then, despite our best intentions. We’ve taken four flights since we quit, one because of a visa glitch, and the others to be with friends and family on special occasions.

Life happens. Here’s how to reduce the environmental impact of your flight, if you absolutely must fly.

Choose the most efficient length for your flights

Very short flights (e.g. less than 1000 km) are inefficient, because a high proportion of the fuel burned for a flight is used for take-off and landing.  But very long flights (more than 5000 km) are inefficient too, because they need to carry so much weight to go further without refuelling.

Ever heard the advice not to fill your car all the way up if you don’t need to, because lugging around the weight of a full fuel tank will cost you? It’s the same with planes.

777-224 fuel burn-range

Fuel burn per distance travelled for a Boeing 777-224, plotted from data in the aircraft’s flight manual. The most efficient length for a journey is about 2500 km. Graph created by Marc Lacoste and shared under the terms of the GNU Free Documentation License.

The most efficient distance for a flight varies from aircraft to aircraft (you can see some figures here), but is usually in the 2000 km to 5000 km range.

Obviously it’s not a green choice to fly further to get the most efficient flight distance, the total emissions will still be less for a shorter flight.

But if you need to travel further than the most efficient journey length, you can reduce your emissions by splitting your journey into multiple flights that fit in the most efficient range. It might even save you money too — direct flights often cost more.

Better still, you can combine a flight with a train or bus journey where possible, to cut down the distance you need to fly. Crossing oceans is often what makes a journey difficult to manage without flights (though not impossible), but you might be able to limit the distance you fly by tacking overland travel onto the start or end of your journey. Crossing continents will give you a great perspective on the land you’re crossing (for example, seeing Russia on the Trans Siberian railway).

If you’re in a hurry, night trains could be the answer. Night trains are usually comfortable, and often cheaper than flying, especially when you factor in accommodation costs saved. And by travelling over night you’re cutting out daytime travel time.

You can travel at night by air, of course, but not in the same comfort, and there’s an environmental snag to this option…

Fly during the day (ideally in summer)

Carbon dioxide emissions aren’t the only way that air travel contributes to global warming. At the risk of discrediting everything that follows, the pretty white contrails you see crossing the sky in the wake of planes aren’t actually harmless. They make a considerable contribution to global warming. In fact, there’s evidence that contrails cause more warming than the carbon dioxide emitted from air travel.


Fortunately, you can do something about this. Contrails don’t form all the time, only in certain atmospheric conditions. They form in moist air at low temperatures, and are much more likely to form at night, and during the winter. By choosing to fly during the day, and preferably during the summer (or dry season), you can reduce the global warming impact of your flight, potentially significantly. A 2010 study found that 25% of UK flights are at night, but that those night flights create 60% of contrail related warming of the atmosphere.

Pick an airline that doesn’t have business class

I’ve mentioned before that flying first class is environmentally ruinous, and business class isn’t much better. Bigger seats, more staff, and more paraphernalia mean that fancier tickets come with much higher carbon footprints. Not only does all this extra stuff mean more weight to carry through the air, so more fuel burned, but having fewer seats in the same space means the emissions for the aircraft itself are split across fewer tickets. A first class flight from London to Rome will create about 25 times the emissions of the same journey by highway bus.

Most of us can’t afford first or business anyway, of course. But apart from “opting out” of first class, you can help contribute to reducing flight emissions by choosing to travel with an airline that doesn’t offer first or business class seats. This can make a huge difference to the number of passengers a flight can carry, and therefore the emissions per passenger. For example, an Airbus A380 has a potential capacity of 850 passengers, but in Etihad’s seat configuration it only has 417 economy seats, with 70 business class seats, and some first class apartments, including a three room suite. Efficient, eh?

You can take even this further and use seat guru to find out which airline has the most seats on the plane for your route. There’s no guarantee the seats will be full of course, but by choosing an aircraft with more seats you can increase the chance of splitting the flight emissions across more travellers, and minimising the environmental impact of your journey.

Pack light

The simplest way to cut back weight carried, and so the emissions from your flight, is to just bring less stuff. Packing light is a bonus in itself of course: less to lug around, less hassle with fitting your luggage on city transport or in storage, and less time spent deciding what to bring or what to wear. But cutting back on your luggage could make a real difference to the emissions from your flight too.  Delta airlines say:

If customers pack lighter — making simple changes like leaving that extra pair of shoes at home [about 1 kg] — the annual environmental impact from reduced fuel consumption is the equivalent to removing 10,500 cars from the road for [an entire] year.

Offset your flight (it probably won’t hurt)

Carbon offsetting is skulking right down at the bottom of the list, because it’s beset by problems. Not least the fact that it lets us greenwash our flying habit.

The measures that carbon offsetting projects are taking, like planting trees, are things we absolutely need to be doing anyway to have any chance of limiting the worst effects of climate change. Placating our guilt about air travel by paying for carbon offsetting lets us off the hook for our high-carbon lifestyles. These lifestyles will never be sustainable on a planet with 7 billion people on it.

The most succinct lambasting of carbon offsetting I’ve seen comes from Jeff Gazzard of the Aviation Environment Federation, quoted in the Guardian:

Asking someone – inevitably in the developing world for reasons of cheapness! – to take on your carbon reduction is morally and ethically indefensible. If you asked an African to give up smoking on your behalf and you carried on how does that improve your health? What if they’ve never smoked in the first place?

[Carbon offset schemes] prevent behaviour change – keep on flying, everything’s fine!

Having said all of that, offset your flight if you absolutely must fly.

It might do some good for the environment, or at least mitigate some harm.

One thought on “How to make flying more eco-friendly, if you really have to fly

  1. Thank you for the excellent tips to reduce our flying carbon footprints. The fuel consumption by distance traveled graph is interesting and makes a lot of sense. To minimize weight and costs, the airlines must only bring enough fuel for the given trip. Unlike with our cars, where we usually top off our tank and only refuel when the gas gauge approaches empty.

    I am encouraged by the recent progress made in electric vehicles, and hope to see that extended to air travel some day in the near future. I look forward to the day when we don’t have to burn petroleum hydrocarbons to get where we want to go.

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