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Decarbonizing The Most Polluting Heavy Industries | Earth Wise

November 23, 2021 By EarthWise Leave a Comment

The production of steel, cement, and ammonia accounts for about 20% of the carbon dioxide humans pour into the atmosphere. Modern cities are largely constructed from concrete and steel and most of our food is grown using fertilizer made from ammonia.

The most widely discussed solutions to decarbonizing these industries are green hydrogen and carbon capture and storage or CCS.

Steel manufacture is responsible for 11% of society’s emissions. Most production starts by burning coal in a blast furnace. Using CCS could reduce emissions from burning the coal. But the blast furnace could be eliminated entirely by the use of electrolysis to produce the pure iron needed to make steel. This would be extremely energy-intensive but using a low-carbon source like green hydrogen could greatly reduce the emissions from making steel.

Ammonia is made by producing hydrogen from natural gas and then combining it with atmospheric nitrogen. Both the hydrogen production and ammonia synthesis are energy intensive. Using green hydrogen would eliminate emissions from the hydrogen production itself and new research on catalysts aims at lower-temperature, less-energy intensive ammonia synthesis.

Decarbonizing cement manufacturing is perhaps the toughest challenge. Cement is made in a high-temperature kiln, typically heated by burning fossil fuels. The process converts calcium carbonate and clay into a hard solid called clinker. The main byproduct of that is even more carbon dioxide. Burning green hydrogen and capturing carbon emission are about the best hope for reducing cement manufacturing emissions.

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Can the World’s Most Polluting Heavy Industries Decarbonize?

Photo, posted June 30, 2009, courtesy of Portland Bolt via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Getting Rid Of Plastic Here And Abroad

May 23, 2019 By EarthWise Leave a Comment

Efforts in the fight against plastic pollution are really stepping up these days.

New York State lawmakers have agreed to impose a statewide ban on most types of single-use plastic bags from retail sales. The ban would be the second statewide ban after California, which banned the bags in 2016. Hawaii effectively also has such a ban since all of the state’s counties have their own bans.

The New York ban would begin next March and would forbid stores from providing customers with single-use plastic bags. There are a number of exceptions, including food takeout bags in restaurants, bags used to wrap deli or meat counter products, and newspaper bags. New York counties could opt into a plan to charge a 5-cent fee on paper bags, with proceeds going to the state’s Environmental Protection Fund. Some environmentalists point out, however, that paper bags have their own issues. While they do decompose in landfills, they have a substantial carbon footprint since they are made from wood and being heavier, they are more costly to ship. Business groups are concerned about the forthcoming ban based on increased costs.

Meanwhile, European Union member states have reached a provisional agreement to introduce restrictions on single-use plastic products. In 2021. European citizens will say goodbye to plastic cutlery, plastic plates and plastic straws among other products.

According to the European Commission, plastics make up 85% of beach litter in the Mediterranean. Large plastic pieces injure, suffocate, and often kill marine animals but microplastics have reached record levels of concentration – over a million fragments per square kilometer – in the Mediterranean.

Both here and abroad, the war on plastics is heating up.

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Plastic Bags to Be Banned in New York; Second Statewide Ban, After California

The End Of Plastic Cutlery, Plates And Straws: EU Market Says Goodbye To Single-Use Plastic Products

Photo, posted March 20, 2007, courtesy of Flickr.

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.