planes

Hydrogen-Powered Jetliners | Earth Wise

December 18, 2020 By EarthWise Leave a Comment

Airbus, the giant European aerospace company, hopes to have hydrogen-powered commercial airliners in the sky by 2035. Such planes would have no carbon dioxide emissions.

Greenhouse gas emissions from commercial aviation have been a rapidly increasing contribution to the global total. Of course, the Covid-19 pandemic has drastically reduced air travel, so emissions are currently lower than they have been in a very long time. But at some point, they will resume at previous levels and continue to increase.

Planes themselves produce over 2% of global CO2 emissions, and between the climate effects of contrails and the emissions associated with the rest of the air travel industry, commercial aviation drives about 5% of global warming.

Airbus is studying design concepts in which planes run off of hydrogen and oxygen fuel and have no carbon exhaust. Making such planes practical and environmentally advantageous requires solving an array of complex technical challenges.

One of the biggest challenges is that the hydrogen on the market today is considered to be “brown” rather than green, meaning that it is not a sustainably produced energy source. Almost all hydrogen produced today comes from natural gas reforming, which results in carbon emissions. A viable hydrogen-powered aviation technology assumes that producing hydrogen by splitting water molecules into oxygen and hydrogen using renewable energy becomes the standard source for it.

There have been test flights of small planes and drones powered by hydrogen, but Airbus expects that intensive research and development for the next five years will be required to evolve its current preliminary designs to a stage where they could be developed for future use in its product line. It won’t happen overnight, but according to Airbus, hydrogen planes are coming.

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Airbus Hopes to Be Flying Hydrogen-Powered Jetliners With Zero Carbon Emissions by 2035

Photo, posted April 15, 2019, courtesy of Olivier Cabaret via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Side Effects Of Geoengineering | Earth Wise

July 20, 2020 By EarthWise Leave a Comment

As the world struggles to reduce the greenhouse gas emissions that are warming the global climate, some researchers are exploring proposals to deliberately engineer climate changes to counteract the warming trend. One of the most widely discussed approaches is to shade the Earth from a portion of the sun’s heat by injecting the stratosphere with reflective aerosol particles. Proponents of this idea point out that volcanoes do essentially the same thing, although generally for only a limited amount of time. Particularly large eruptions, such as the Krakatowa eruption of 1883, wreaked havoc with weather around the world for an entire year.

Schemes to launch reflective aerosols – using planes, balloons, and even blimps – appear to be quite feasible from the standpoint of physically accomplishing them. But this says nothing about the political, ethical, and societal issues involved. The point is that such an approach could indeed lower global temperatures and thereby potentially offset the warming effects of greenhouse gases.

A study by scientists at MIT looked at what other effects such a solar geoengineering project might have on the climate. Their modeling concluded that it would significantly change storm tracks in the middle and high latitudes. These tracks give rise to cyclones, hurricanes, and many more ordinary weather phenomena.

According to the study, the northern hemisphere would have weakened storm tracks, leading to less powerful winter storms, but also stagnant conditions in summer and less wind to clear away air pollution. In the southern hemisphere, there would be more powerful storm tracks.

Aside from turning the world’s weather patterns inside out, solar geoengineering would do nothing to address the serious issue of ocean acidification caused by increasing carbon dioxide levels.

As many have pointed out, playing the geoengineering game would have many unintended consequences.

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Study: Reflecting sunlight to cool the planet will cause other global changes

Photo courtesy of MIT.

Earth Wise is a production of WAMC Northeast Public Radio.

Amazon And Climate Change

October 30, 2019 By EarthWise Leave a Comment

Online shopping giant Amazon has unveiled a Climate Pledge, committing to meet the goals of the Paris climate agreement ten years ahead of schedule, and to be carbon neutral by 2040. This is the company’s most ambitious push yet to reduce its carbon footprint, which currently rivals that of a small country. In fact, Amazon is responsible for 48.9 million tons of carbon dioxide last year, which is about 85% of what Switzerland typically emits in a year.

Amazon, which ships more than 10 billion items a year on fossil fuel-intensive planes and trucks, has ordered a fleet of 100,000 electric vans that will start delivering packages to doorsteps in 2021. The vans will be made by Rivian, a Michigan-based company that Amazon invested in earlier this year.

Amazon plans to get 100% of its energy from solar and other renewable sources by 2030. Currently, it gets about 40% of its energy from renewables.

Amazon is also investing $100 million in nature-based climate solutions and reforestation projects around the world in order to remove carbon from the atmosphere.

While announcing these initiatives recently at the National Press Club in Washington, D.C., Amazon CEO Jeff Bezos said the company needs to be a leader on the climate change issue:

We want to say look, if a company of Amazon’s complexity, scale, scope, physical infrastructure, delivering 10 billion items can do this, so can you.

After revealing Amazon’s Climate Pledge, Bezos said he would talk with CEOs of other large companies to try to get them to also sign it. You can find a link to Amazon’s progress on its commitments by visiting this website.

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‘Middle of the herd’ no more: Amazon tackles climate change

Amazon: Committed to a sustainable future (track progress here)

Photo courtesy of Amazon.

Earth Wise is a production of WAMC Northeast Public Radio.

Hybrid-Electric Aircraft

May 20, 2019 By EarthWise Leave a Comment

The commercial aviation industry is a major source of carbon dioxide emissions and, as other industries try to move towards decarbonization, its share is getting larger. But reducing emissions from aircraft is challenging because powering planes without burning fossil fuel is hard to do.

The biggest problem is that powering aircraft with electric motors instead of fossil fuel motors requires so much energy that the batteries needed to supply it become impractically heavy. While research goes on to develop lighter-weight batteries, an interim concept may pay dividends.

Just as hybrid cars represent a stepping stone towards full electrification, hybrid-electric aircraft may be a way to obtain substantial reductions in aircraft emissions. The idea is to use battery-powered electric motors to power planes, but to greatly reduce the capacity requirements of the batteries by having an on-board fossil-fuel generator to charge the batteries and supply additional needed power.

A study by the University of Illinois looked at the potential emissions reductions for hybrid-electric aircraft taking into account the emissions associated with generating the electricity that charges the batteries in the plane. The requirements in the study were that the plane needs to be able to carry the same number of passengers and travel the same distance as current aircraft.

The results were that a drivetrain that gets 50% of its power from battery charge reduced emissions by about 50% over the full lifecycle of the plane.

As batteries get lighter and the electric grid gets greener, the possibility of making major reductions in aircraft carbon emissions looks increasingly realistic. But there is a long way to go.

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Study Examines Commercial Hybrid-Electric Aircraft, Reduced Carbon Emissions

Photo, posted September 26, 2014, courtesy of Jeff Turner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Traffic Jams In The Jet Stream

July 13, 2018 By EarthWise Leave a Comment

Many extreme weather events are associated with unusual behavior by the jet stream. Jet streams are the global air currents that circle the earth. The meandering and speed changes in the jet stream affect weather and also play a big role in how long it takes aircraft to make their way across the country. The behavior that leads to extreme weather events is known as “blocking” in which the meandering jet stream stops weather systems from moving eastward.

Transportation And Greenhouse Gases

January 17, 2018 By EarthWise Leave a Comment

Power plants have been the biggest source of greenhouse gas emissions in the United States for more than 40 years. But the ever-changing picture of electricity production has changed that situation. According to new data from the government’s Energy Information Administration, transportation has now taken over the top spot.

Turning Emissions Into Fuel

January 8, 2018 By EarthWise Leave a Comment

Reducing carbon dioxide emissions is an essential element in mitigating climate change. The best approach is to not produce the stuff in the first place and the ongoing transition away from fossil fuels is trying to do just that. But realistically, fossil fuels will be with us for a long time to come. Given that, additional approaches are necessary.

Turtles Delay Flights

August 11, 2017 By EarthWise

Recently, we talked about the problems New York’s native turtles have during their mating season as they cross roads and highways seeking places to lay their eggs. The state Department of Environmental Conservation even issued recommendations for how people can help turtles avoid getting crunched by cars.

Reducing Emissions From Ships And Planes

June 28, 2016 By WAMC WEB

The global efforts to reduce carbon emissions are marked by a conspicuous omission: the aviation and shipping industries. These two industries contribute 6% of all man-made CO2 emissions, but have so far managed to avoid international control. And not only are they major sources of carbon emissions, their contributions are growing three times faster than overall global CO2 emissions.