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David Keith

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The Cure for Flygskam

Qantas, the Australian airline, has just test-flown the world’s longest commercial air-route: 10,200 miles (16,500 km.) from New York non-stop to Sydney. There were only 60 passengers aboard the Boeing 787, all in business class, because the plane needed all the rest of the weight for fuel. And, we are told, they danced the Macarena in the empty economy class to stay limber during the 19-hour flight.

I don’t think Greta Thunberg would have been pleased.

There is a Swedish neologism, ‘flygskam’, that has gained some currency among environmental activists in Europe. It means ‘flight-shame’, which is the emotion righteous people should feel if they take a plane trip and contribute to global heating.

Ms Thunberg took a sail-boat across the Atlantic because the fuel that is burned to get each airline passenger to North America causes warming equivalent to about 10% of the average Swede’s annual ‘carbon footprint’. A bit dramatic, maybe, but her point was that flying causes major emissions, and the only way to avoid them is not to fly.

Aviation accounts for around 2.5% of human-caused greenhouse gas emissions at the moment, but the contrails the planes leave in the stratosphere turn into cirrus clouds that reflect heat back to the surface, and that causes an equal amount of heating.

So in reality 5% of current warming is already due to aviation, and industry representatives estimate that the number of people flying annually will almost double (to 8.2 billion) in the next twenty years. By then flying will have grown to 10% of the global heating problem, or even more if we have made good progress on cutting our other emissions. So must we stop flying?

That’s not the way we deal with other climate-related transport problems. We haven’t abolished automobiles; we have just worked on ways of reducing and ultimately eliminating the emissions associated with them. Electric cars now lead the field, but other alternatives may emerge.

By contrast, we are told, there are no alternatives available for aviation.

People have been nibbling around the fringes of the fuel problem, but ‘biofuel’ won’t cut it: it would take an area the size of Australia to grow the plants needed as feedstock for the fuel that aviation industry consumes. Batteries are too heavy to use in electric planes, and there’s no solution for the contrail problem. We’ll just have to stop flying.

Not necessarily. The problem has been neglected, because the aviation industry was too lazy or stupid to look down the road and start preparing for a future that more attentive people could see twenty years ago. But the fuel problem is not insoluble. In fact, it has already been solved. The solution just needs to be scaled up.

A number of people have been working on DAC (Direct Air Capture of carbon dioxide) for more than a decade already, and the leader in the field, David Keith’s Carbon Engineering, has had a pilot plant running in British Columbia for the past three years.

Keith’s business model involves combining his captured carbon dioxide with hydrogen (produced from water by electrolysis). The electricity for both processes comes from solar power, and the final product is a high-octane fuel suitable for use in aircraft.

It emits carbon dioxide when you burn it, of course, but it’s the same carbon dioxide you extracted from the air at the start. The fuel is carbon-neutral. Scaling production up would take a long time and cost a lot, but it would also bring the price down to a commercially viable level.

The contrails and the cirrus clouds in the stratosphere are a considerably harder problem, but there are a number of measures that would help.

The planes are flying so high for two reasons. The air is less dense up there, so you don’t use so much fuel pushing through it. But the main reason, especially for passenger planes, is that there is much less turbulence in the stratosphere than in the lower atmosphere. If the planes flew down there, they’d be bouncing around half the time, and everybody’s sick-bag would be on their knee.

So what can you do about it? Well, contrails only form in air masses with high humidity, and therefore only affect 10-20% of flights. With adequate information, most of those flights could simply fly around them. Alternatively, fly below 25,000 ft. for that section of the flight, and contrails won’t form anyway.

It will be more turbulent down there, so in the long run we should be building aircraft that automatically damp out most of the turbulence. This is probably best achieved by ducted flows of air that instantly counter any sudden changes of altitude or attitude, but if aircraft designers started incorporating such ducts into their designs today, they’d only come into regular use in about fifteen years’ time.

So the order of business is first, carbon-neutral fuels (half the problem solved); second, flying around or under air masses with high humidity (another quarter solved); and finally, turbulence-damping aircraft technology (most of the rest done).

By the way, how is Greta Thunberg getting home again?
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To shorten to 725 words, omit paragraphs 7, 8 and 9. (“That’s not…flying”)

Gwynne Dyer’s new book is ‘Growing Pains: The Future of Democracy (and Work)’.

Fuel from the Air

20 October 2012

Fuel from the Air

By Gwynne Dyer

Stockton-on-Tees, a small city in northeastern England, has only one claim to fame: the first railway tracks were made and laid in the city in 1822, and the first-ever train ran on those tracks in 1825. But it might one day have another claim, also related to transportation: a locally based start-up company called Air Fuel Synthesis has just produced the first petrol (gasoline) from air and water.

It isn’t a lot of petrol – five litres (one gallon) in two months – but Peter Harrison, the company’s chief executive, hopes that within two years they will build a larger plant producing a tonne a day. He envisages refinery-scale operations within fifteen years.

“We’ve taken carbon dioxide from air and hydrogen from water and turned these elements into petrol,” Harrison told a conference at the Institution of Mechanical Engineers in London. Since the carbon dioxide that goes into the air when this fuel is burned exactly equals the amount that was taken out of the air when it was fabricated, it is a carbon-neutral fuel. Provided, of course, that the electricity used in the process comes from renewable sources.

No wonder that people who worry about global warming are excited about this breakthrough – but they should get excited slowly. The question was never IF you could create a complex hydrocarbon like petrol from just air and water, but HOW MUCH it costs to do it, compared to just pumping oil out of the ground and refining it.

The answer in the past has been: far too much. Splitting water molecules to get hydrogen is expensive in terms of the electricity required. Carbon dioxide is easily available as the by-product of burning coal or oil, but using that CO2 as the feedstock for artificial petrol only postpones the moment when it gets into the atmosphere by a few days or weeks.

If you want a truly carbon-neutral fuel, then the carbon dioxide you use must come straight from the air. Prototype machines have been built (by Klaus Lackner of Columbia University and David Keith of the University of Calgary) that can extract CO2 from the air in industrial quantities, but the price per tonne at the moment is about $600.

That’s far too much, but as Lackner points out, the cost of any new technology plunges steeply once it goes into volume production. And the cost of getting hydrogen from water may also drop dramatically. Daniel Nocera of the Massachusetts Institute of Technology, has developed a catalyst made from cobalt and phosphorus that can split water at room temperature.

“I’m using cheap, Earth-abundant materials that you can mass-manufacture,” Nocera said in 2008. “As long as you can charge the surface, you can create the catalyst, and it doesn’t get any cheaper than that.” So if the hydrogen is cheap, and the cost of extracting carbon dioxide from the air also falls dramatically, how much would it cost to combine them into petrol?

That’s what Air Fuel Synthesis is working on: an integrated, scalable industrial process that takes carbon dioxide from the air and hydrogen from water, combines them into methanol, and then turns that into petrol.

Peter Harrison is cagey about his current production cost per litre: at the “proof-of-principle” stage, everything costs a fortune. But as he told “The Independent” in a recent interview, “You’re in a marketplace where the only way is up for the price of fossil fuel. At some point there will be a crossover where our fuel becomes cheaper.”

David Keith sees it the same way. “You’re selling this fuel, and they’re burning it, putting carbon in the air, but then you’re recapturing the same amount of carbon and selling it to them again. That’s a business model that could conceivably take a whack at the global transportation market, which is the hardest part of the climate problem to attack.”

Maybe Harrison’s process will not win the race to capture that market. Maybe the cheaper option will be to grow green algae in waste water or salt water, crush it to extract the oil from it, and then refine the oil into petrol, diesel and so on. (Exxon-Mobil is currently spending about $100 million a year to develop that process.) But one way or another, the petrol we put in our vehicles in 25 years’ time will probably not come out of the ground.

An entire industry employing millions of people, and the national budgets of entire countries, and much of the military planning by the world’s great powers, all rest on the assumption that this will never happen. Of course it will. The pressure to cut greenhouse gas emissions will grow as the temperature rises, and the desire for “energy independence” will only get stronger as oil price rises.

Back in the 1890s, it was still unclear whether the new “horseless carriages” would ultimately be powered mainly by petrol, steam or electricity. But it was already clear to those with any understanding of the interactions between markets and technology that the day of the horse-and-buggy was over, and the smart money was already getting out of buggy whips.

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To shorten to 725 words, omit paragraphs 8, 9 and 14. (“I’m…petrol”; and “An entire…whips”)

NORTH AMERICAN PAPERS PLEASE NOTE: “petrol” should be replaced by “gas” or “gasoline” throughout the article.