society

Reducing emissions from cement

November 14, 2024 By EarthWise Leave a Comment

Cement production accounts for about 7% of global carbon emissions. It is one of the most difficult challenges for emissions reduction. The emissions associated with producing cement come from both the energy used to provide heat for the process and from the chemical reactions that take place in the formation of cement. Cement is an essential building block of society, and its use is not expected to decline over time.

A German company called Heidelberg Materials is embarking on an ambitious project to reduce carbon emissions from a cement plant in Norway. They are building a facility to use absorbent chemicals to capture large quantities of carbon dioxide emitted through cement production. More than half a ton of carbon dioxide arises from every ton of cement produced at the plant.

Once the carbon dioxide is captured it will be chilled to a liquid, loaded onto ships, and carried to a terminal farther up the Norwegian coast. From there, it will be pumped into undersea rocks located 70 miles offshore and a mile and a half below the bottom of the North Sea.

With all of this complicated process going on, cement from the plant is likely to be quite expensive. It might even be two or three times the price of ordinary cement. Heidelberg Materials is counting on customers’ willingness to pay much more for cement that comes with green credentials.

Can this be economically viable? Heidelberg estimates that cement accounts for only about 2% of the cost of a large building project but as much as 50% of the emissions. As a result, using carbon-free cement could be a relatively inexpensive way for builders to reduce emissions.

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Cement Is a Big Polluter. A Plant in Norway Hopes to Clean It Up.

Photo, posted May 7, 2016, courtesy of Phillip Pessar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Controlled Environment Agriculture | Earth Wise

October 24, 2023 By EarthWise Leave a Comment

The term “controlled environment agriculture” (or CEA) refers to any number of systems embodying a technology-based approach to farming. CEA can range from simple shade structures to greenhouses to full indoor or vertical farms. At the most advanced level, CEA systems are fully automated, closed loop systems with controlled lighting, water, and ventilation. Many systems make use of hydroponics rather than traditional soil.

The goal of CEA systems is to provide optimum growing conditions for crops and prevent disease and pest damage.

A recent study by the University of Surrey in the UK sought to understand the impact of using CEA systems to grow lettuce, which is a high-value crop that is often grown in such systems.

The study found that, on average, CEA methods produce double the crop yields compared to field-based agriculture. They also found that the cultivation time of CEA yields was, on average, 40 days. This compares with an average cultivation time of 60-120 days for field-based agriculture. More specifically, production of lettuce using CEA was 50% faster in the summer and up to 300% faster in the winter.

Climate change presents many difficult challenges to society, not the least of which is its threat to food security. Controlled environment agriculture could allow cultivation of crops in harsh environments and in the face of changing climates. Quantifying the benefits CEA can have on yield and growth provides important information for advancing our understanding of where and when this technology can bring the most value to society.

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Using artificial methods for growing crops could help solve global food security

Photo, posted February 24, 2013, courtesy of Cindy Kurman / Kurman Photography via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Paper Cups Are Not So Great | Earth Wise

October 4, 2023 By EarthWise Leave a Comment

The environmental cost of plastic waste is a highly visible global issue. The response has been a growing effort to replace plastic items with alternative materials. One very visible change of this sort has been the replacement of plastic cups with paper cups at coffee shops. But a new study at the University of Gothenburg in Sweden has found that this solution has problems of its own.

Researchers studied the effects of disposable cups in the environment on the larvae of the butterfly mosquito. They placed disposable cups made from different materials in wet sediment and water for a few days and observed how the chemicals leached from the cups affected the growth of the larvae. It turned out that all of the different kinds of cups had negative effects. The concern is not specifically about mosquito larvae; it is the fact that more environmentally friendly drinking cups are still potentially harmful to living things.

Paper is neither fat nor water resistant, so paper cups need to be treated with a surface coating. The most common coating is polylactide, which is a type of bioplastic. It is generally considered to be biodegradable, but the study shows that it can still be toxic. Bioplastics still contain many different chemicals and the potential toxicity of each of them is not well known.

The UN is trying to develop a binding agreement by the world’s countries to end the spread of plastics in society and nature. For such an agreement to be effective, the plastics industry will need to clearly report what chemicals all products contain, including such mostly invisible products as the coating on paper drinking cups.

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Paper cups are just as toxic as plastic cups

Photo, posted October 23, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More Extreme Weather | Earth Wise

November 23, 2020 By EarthWise Leave a Comment

If it seems like natural disasters happen more frequently than they used to, that is because they do. A new report from the United Nations entitled “The Human Cost of Disasters 2000-2019” provides the facts. From 2000 to 2019, there were 7,348 natural disasters around the world, compared with 4,212 natural disasters from 1980-1999.

The culprit is the climate. Climate-related disasters increased from 3,556 events during the 1980-1999 period to 6,681 in the past 20 years, again an increase of more than 3,000.

The global economic losses associated with natural disasters have been staggering. The earlier 20-year period saw $1.63 trillion in losses while the recent period resulted in $2.97 trillion in losses. Disasters killed 1.19 million people in the earlier period and 1.23 million in the recent period. It is a testimonial to the skills and efforts of disaster management agencies, civil protection departments, fire brigades, public health authorities, the Red Cross and Red Crescent, and many NGOs that the cost in human lives was not much greater over the past 20 years.

According to a statement from the UN, human society is being willfully destructive. They draw that conclusion in light of reviewing the disaster events over the past 20 years and seeing the failure of society to act on science and early warnings to invest in prevention, climate change adaptation, and disaster risk reduction.

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