Come 2017, British Airways could be able to fuel flights from London's City Airport to New York's John F. Kennedy International Airport on trash.

The airline has partnered with Washington, D.C.-based Solena Fuels to make 50,000 metric tons of jet fuel from municipal solid waste per year. It is the first project in the world to attempt to convert trash into a drop-in fuel for airplanes.

British Airways agreed in 2012 to buy the jet fuel from Solena per year over 11 years at "market competitive prices," about $510 million for the price of conventional jet kerosene. Last month, the London Green Sky Project, as it's called, found a home: a 20-acre lot east of London that was formerly the site of a large oil refinery.

Green Sky will use the existing waste collection system to pick up household trash and take advantage of the electricity infrastructure that serviced the refinery up to its closure in 2012. Solena is in negotiation with a number of local waste companies that could provide the waste for the facility, according to a British Airways spokeswoman.

The technology isn't cheap, said Jonathon Counsell, head of environment for British Airways. About $600 million was invested to develop Solena Fuels' gasification-Fischer-Tropsch combination technology for solid waste. But the payoff will be worth it.

"What we get from that is a very pure, high-quality fuel," said Counsell, at the Advanced Biofuels Leadership Conference in National Harbor, Md., Wednesday. Turning trash into fuel yields twice the energy that incinerating the waste for electricity would provide, he added. Recent life-cycle analyses indicate that the fuel could reduce greenhouse gas emissions by up to 95 percent compared to fossil fuels, said Counsell. This doesn't include the avoided methane emissions -- a gas with 30 times the global warming potential of carbon dioxide -- that result from trash decomposing in a landfill.

A century-old process at work

Solena Fuels will use a combination of two technologies to make the fuel. Once the waste has been cleaned of any hazardous or recyclable materials, it will be combusted in a low-oxygen environment that produces a synthesis gas of hydrogen and carbon monoxide, a process known as gasification. The gas will then be converted to liquid fuel, in a process called Fischer-Tropsch.

British Airways jet

"When people hear that word, it seems to be like rocket science," said Solena Fuels President and CEO Robert Do, who fined-tuned the process for organic waste. The Fischer-Tropsch process has been in use for nearly a century to turn natural gas or coal into liquid fuel. In fact, said Do, British Airways has long purchased its jet fuel from the South African energy company Sasol, which makes fuels from coal.

To start, the impact of converting British Airways' business flights would be minuscule. Fueling the London-to-New York trips with biofuel would displace about 2 percent of British Airways' consumption at its main hub -- Heathrow Airport outside of London. But the airline expects to increase its use gradually, in compliance with a U.K. aviation industry road map that sets the goal of obtaining 30 percent of fuels from renewable sources by 2050.

Keeping the project small also helps reduce risk, said Do, an aspect that attracts project financing. Solera has similar agreements with two other airlines, Lufthansa and Qantas.

Do expects the project will serve as a prototype for similar projects around the world, where trash disposal has become a growing problem.

"Every city in the world today is experiencing difficulties in handling its waste, whether it's New York City versus London versus Istanbul versus Hong Kong," said Do.


Multiple ways to replace petroleum

According to Nancy Young, vice president of environmental affairs at the trade group Airlines for America (A4A), municipal solid waste represents a promising alternative fuel pathway for the industry. One major advantage is that the feedstock can be sourced and produced near airports, mitigating transportation and logistics costs.

In 2010, a number of U.S. airlines signed a letter of intent to work with Solena on developing fuel from waste, and they are likely to revisit that opportunity once the British Airways project gets off the ground, said Young. In the meantime, the U.S. aviation industry is working with the Connecticut Center for Advanced Technology, through a grant from the Department of Agriculture, to foster the development of a fuel made from municipal solid waste.

Airlines are also testing fuels from other feedstocks. Lufthansa, which in 2011 became the first airline to use biofuels in commercial flights, announced this week that it's researching a new type of biofuel made from fermented plant waste by the U.S.-based company Gevo.

Airlines are putting alternative fuels into action, too. United Airlines, for instance, has an agreement with AltAir Fuels to run flights out of Los Angeles later this year on a commercial-scale, renewable jet fuel made from agricultural waste and nonedible natural oil products. Alaska Airlines also has a purchase agreement in place with Hawaii Bioenergy to fly on a sustainable jet fuel made from woody biomass on flights starting 2018.

In 2006, a coalition of airlines, aircraft and engine manufacturers, energy producers, researchers and U.S. government agencies formed the Commercial Aviation Alternative Fuels Initiative (CAAFI) to promote the development of alternative jet fuel options. USDA, the Federal Aviation Administration, A4A and Boeing also formed the "Farm to Fly" program in 2010 to accelerate the development of commercially viable alternative fuels for aviation.

The airline industry is eager to increase its fuel options because planes simply cannot run on electricity the way cars and trucks can. Today, airlines are restricted to using petroleum-based fuel, which represents the industry's single largest expense and a growing source of greenhouse gas emissions.

'Farm to Fly' goes aloft

"Airlines are really focused on alternative fuels for two reasons," said Young. "One is to provide a competitor to petroleum-based fuels for supply and price volatility reasons. On the other side is the sustainability and emissions goals that we have. Providing some amount of sustainable alternative aviation fuel is very important in meeting those."

The global aviation sector currently accounts for about 2 percent of global emissions, but its carbon footprint is expanding quickly as demand for air travel increases. To mitigate its environmental impact, the industry has committed to improving fleet efficiency 1.5 percent per year and to achieving carbon-neutral growth from 2020.

Farm to Fly created the aspirational goal of adopting 1 billion gallons of sustainable alternative jet fuel -- about 6 percent of the industry's current annual fuel consumption -- by 2018. Young said reaching that goal is a stretch, but not impossible should fuel supplies substantially increase and the price drop.

Allen Hershkowitz, a senior scientist at the Natural Resources Defense Council, said he applauds the aviation industry's effort to move from fossil fuels. But he added that municipal waste isn't necessarily an environmentally friendly feedstock.

If plastic that can be recycled or food that can be composted is being turned into fuel and burned off without recouping its additional value, those materials aren't following an ecologically optimal disposal route, he said. And even if fuel producers do commit to recycling, will they remove only what's economically recyclable, or what's technically recyclable?

The composition of the waste and how it's managed will have a significant impact on the sustainability profile of the fuel, said Hershkowitz.

"I would say there needs to be a refined understanding of the physical characteristics that are being converted into the fuel," he said. "If those physical characteristics allow for the material to be recycled, it should be recycled. If they carry zero Btu [British thermal units], they should be landfilled. If it can't be recycled and has Btus, then exploring the conversion into a transportation fuel makes sense."