Former Airline Pilot, Researcher, Speaker and Author of “Will Sustainability Fly?”
Sustainable Jet Fuel; What Do You Need to Know?
Hop into the average family car in 1960: Elvis is on the radio (AM radio) singing It’s Now or Never and you are moving about 14 miles for every Imperial gallon of gasoline you burn. In today’s SI parlance, that’s nearly 20 liters per hundred kilometers travelled. These days you will burn only about forty per cent of that amount … again, on average. But you’re not average, surely. If you own a nice little hybrid, your fuel consumption could be only a quarter of what it was back then.
If lots of people didn’t really care in those days, well … gas was cheap and being on the road was fun: boys and girls driving up and down the main drag, checking each other out was considered a very normal pastime. The oil crisis of the 1970s changed things … a bit. So did the rising awareness of global warming and climate change.
Anyway, that’s road travel. At the airport, things were, and are, different. Airplanes burn huge amounts of expensive fuel, and so the push has always been on to make them absolutely as efficient as possible. Having worked hard all along, subsequent efficiency improvements have not come so easily. Still, air travel fuel consumption has been cut nearly in half and continues to be reduced. Pretty good. Does that mean the battle to control greenhouse gas (GHG) emissions from airplanes will be won in this way? Hardly. The growth in commercial aviation is approximately 5% per annum, compounding. Efficiency improvements in the coming years might—might—maintain a historical trend on the order of 2% a year. So, despite all our efforts to make airplanes produce a lower volume of GHG, those emissions will grow by something on the order of 3% each. Where does that leave us in, say, 2050? From a 2005 baseline—and unless we do much more than continue to improve efficiency, GHG emission will grow by a factor of about 4, despite ongoing best efforts to control it.
That is a stunning conclusion; in the face of massive efforts to shrink emissions in every sphere of human activity as we move into the future, commercial flying will go the wrong way in leaps and bounds.
Well, the industry is entirely aware of all this and the foregoing arithmetic has compelled commitment to turn things around. In fact, goals have been set: No increase in emissions after 2020; a 50% reduction in absolute amount of emissions by 2050. Truly commendable. But how will such reductions be achieved? And then (almost hate to ask) is it enough? Answering the second question first: No, it’s not enough. The Intergovernmental Panel on Climate Change (IPCC) Special Report 1.5 says that all-sector total, global emissions must fall 45% by 2030 and be at zero (0) by 2050. We have no time. This makes the ‘how’ matter even more interesting and urgent.
There are really only two ways to do it: (1) Offsets. Commercial air must resort to market-based measures dealing in carbon credit for initiatives that can start reducing atmospheric carbon right away. But (2) we must find a way to produce flight energy in a zero-carbon manner. There are just not enough carbon offsets in the world to bring aviation from quadruple its current emissions profile down to zero.
Aviation fuel; We might better talk about “Flight energy,” because there will come a day when we will get the energy required to keep us flying from hydrogen, or electricity stored aboard airplanes. Nevertheless, at large, commercial, aircraft scale, it will be a very long time before that happens. How do we know? Development time for new aircraft—even ones that use more or less current, well understood technologies—is a matter of many years. If we knew what sort of different airplane we wanted to make in the future, it might be ten years from today before we could get the first certified type into production. We would then have to gradually develop different types—for different size and speed requirements—and build out the entire global fleet, extant at that time. Now, each new large aircraft constitutes an investment of hundreds of millions of dollars. That’s too much money to throw away on something that we use for only a short while. The airplanes that we build today will be in service for decades—and we have no immediate, feasible, near-future plans to build anything else. We will rely on our current source of flight energy—kerosene—for a very long time. A huge portion of the commercial fleet operation will burn something like eighteenth century “coal oil” right up to and through 2050.
“Well, if we’re stuck with kerosene, we’re screwed. I know where kerosene comes from.” Yeah, well, the trick is to stop taking fossil deposits of hydrocarbons out of the ground. More precisely, the trick is to take carbon that is already in the atmosphere and use that to make new hydrocarbons.
Surprisingly, there are ways to do that. In fact, there are so many ways that this subject alone could be blogged about indefinitely. That cues my last point: We want low-carbon fuels in order for aviation to become more sustainable. But it would be an error to go about the low-carbon fuel project in a way that is, itself, unsustainable. The point is, it now becomes very important to know what “sustainable” means, because our challenge is too large; we can’t create two or three new problems each time we tackle an existing problem.
That bugbear word: “Sustainability.” It is a term that is thrown at us relentlessly and, oftentimes, on such a vague premise that we’re left thinking that it has no meaning. It does have a meaning. And commercial air travel is such a big, high-profile, expensive, activity that we really need to get at an honest, useful, and rigorous understanding of the concept.
What it is not: Suppose that I run a factory and I manufacture, say, keyrings. I tell my employees, and my customers, and my board of directors that our operation and our products are sustainable. I say this because we have reduced our energy use by 20%, our paper use by 80%, and our water use by 95%. These are great numbers! This is real improvement! … I think. But it doesn’t, of itself, constitute sustainability, or sustainable keyrings, because there are so many other questions. Where do we get the energy, paper, and water that we do use? Are these supply chain components sourced sustainably? What are our suppliers’ understandings of sustainability? And what about inputs beyond energy, paper, and water?
True sustainability is a target concept; it implies perfection in our campaign to make an activity endurable or “perpetual”—to render it something that does no significant or lasting damage. Whether it’s a one-time action or an ongoing activity, it does no real harm. No real harm to what? Well, for starters, the environment—both local and global.
But, in 2019, we are way beyond “for starters;” we are way beyond thinking that our problems start and end with global warming. And it is the very size of the global warming challenge that has allowed us to start seeing things at a more appropriate scale: getting the carbon out of a global economy that is based upon carbon has to be recognized as a task that involves everyone and everything. The climate change hurdle shows us that, ultimately, we cannot have perfectly unharmed local and global environments unless we have the support of the people who could otherwise mess them up. However, we cannot get universal support without universal social justice. That means that if our action—no matter how small or incremental or incipient—is intended to help the world move toward sustainability, environmental benignity in everything we source is complemented by social justice for everyone affected by the activities in both our operations and our supply chains. That is a tall order, but understanding where we are trying to go helps us know how to begin; we start to see beyond our direct consumption of such things as energy, paper, and water, and we become guided by fundamentals that ensure that our initiatives have lasting value and that they will not run into trouble in the longer run.
Sustainability will only be credible to the public when the standard to which it measures itself is known, understood, relevant, and, well, measurable. It certainly has to be a standard that allows a claim of carbon reduction to be reliably assessed as true or false. But it must also speak in the language of other environmental dimensions, and as to whether people affected are being treated fairly so that we can decide whether a particular carbon reduction initiative should be pursued.
We must have sustainably produced no/low-carbon fuel. And remember that in the meantime, we must have sustainably generated carbon credits. These also, must be achieved and assessed using as perfect a sustainability standard as we can conceive.
Our physical world is failing because of human activity. We have to find answers. This is not the time to ad lib a recipe. We need to bring our best minds to the task of describing exactly what we need to do and how to do it.