building materials

Artificial plants to clean indoor air

December 12, 2024 By EarthWise Leave a Comment

The average American spends about 90% of their time indoors breathing the air in our workplaces, homes, or schools. The quality of this air affects our overall health and well- being. Indoor air quality is an issue because many sources can generate toxic materials, including building materials, carpets, and more. But high levels of carbon dioxide are a health hazard themselves. Indoor CO2 levels can often be 5 to 10 times higher than the already heightened levels in the atmosphere.

Many of us make use of air purification systems, which can be expensive, cumbersome, and require frequent cleaning and filter replacements.

Researchers at Binghamton University in New York are working to develop artificial plants that consume carbon dioxide, give off oxygen, and, as a bonus, generate a little electricity. These artificial plants make use of the artificial light in the indoor environment to drive photosynthesis. They achieve a 90% reduction in carbon dioxide levels, which is far more than natural plants can achieve.

The Binghamton researchers had been working on bacteria-powered biobatteries for various applications, but they repurposed the work into a new idea for artificial plants. The artificial plants have “leaves” containing a biological solar cell and photosynthetic bacteria. Their first plant had five leaves and demonstrated promising carbon dioxide capture rates and oxygen generation. It also produced a little electricity. If its generating capacity can be improved, it might also be useful for charging cell phones or other practical applications.

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Binghamton researchers develop artificial plants that purify indoor air, generate electricity

Photo, posted October 13, 2012, courtesy of F. D. Richards via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

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

Conspicuous Consumption

February 6, 2020 By EarthWise 2 Comments

Human civilization consumes vast amounts of material. The Circle Economy think tank actually puts some numbers on it. According to their latest report, the amount of material consumed by humanity has passed 100 billion tons every year. So, on average, every person on Earth uses more than 13 tons of materials per year.

That number has quadrupled since 1970, which is far faster than the population, which has only doubled during that time. In the past two years alone, consumption has jumped by more than 8%. While this has been going on, the proportion being recycled has been falling.

Of the 100 billion tons of materials, half of the total is sand, clay, gravel, and cement used for building, along with other minerals used for fertilizer. Coal, oil and gas make up 15% and metal ores 10%. The final quarter are plants and trees used for food and fuel. About 40% of all materials are turned into housing. A third of the annual materials consumed remain in use, such as in buildings or vehicles. But 15% is emitted into the atmosphere as greenhouse gases and a third is treated as waste.

The global emergencies of climate change and disappearing wildlife have been driven by the unsustainable extraction of fossil fuels, metals, building materials, and trees. The authors of the report warn that if we continue to treat the world’s resources as limitless, we are heading for a global disaster.

The Circle Economy think tank promotes the idea of a circular economy in which renewable energy supports systems where waste and pollution are reduced to zero. Some nations are taking steps towards circular economies, while others are not. This is a problem we can’t allow to be unaddressed.

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World Consumes 100 Billion Tons of Materials Every Year, Report Finds

Photo, posted March 13, 2015, courtesy of Joyce Cory via Flickr.

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Carbon Capture As Big Business

December 26, 2019 By EarthWise Leave a Comment

Removing greenhouse gasses from the atmosphere is an essential part of the overall effort to achieve zero net carbon emissions and stabilize the climate. Since we have not been able to reduce emissions fast enough to do the job, it is important to find ways to pull carbon dioxide out of the atmosphere.

There are many ways to do it, but they tend to be rather expensive and, so far, the need to mitigate climate change does not seem to provide sufficient incentive. A new study by researchers at UCLA, the University of Oxford, and five other institutions, analyzed the possibility of creating a large global industry based on capturing carbon dioxide and turning it into commercial products.

The study investigated the potential future scale and cost of 10 different ways to use carbon dioxide, including in fuels and chemicals, plastics, building materials, soil management, and forestry. The study looked at processes using carbon dioxide captured from waste products that are produced by burning fossil fuels as well as by simply capturing it directly from the atmosphere. The study also looked at processes that use carbon dioxide captured biologically by photosynthesis.

The conclusions of the study were that on average each of the ten utilization pathways could use about half a billion tons of carbon dioxide that would otherwise escape into the atmosphere. Thus, theoretically, these various pathways could take more than five billion tons of CO2 out of the atmosphere. Currently, fossil fuel combustion emits about 40 billion tons of carbon dioxide.

The authors of the study stress that there is no silver bullet in the fight against climate change. It will require multiple approaches – including CO2 removal for industrial use – to make real progress

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Carbon dioxide capture and use could become big business

Photo, posted September 18, 2015, courtesy of Tony Webster via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Smarter Prospecting

November 18, 2019 By EarthWise Leave a Comment

The global demand for copper and gold continues to grow. Copper is widely used in building materials, plumbing, and electronics. Gold is still highly valued for jewelry and coinage, but nearly a third of the world’s gold is now used in electronics.

Both of these metals are getting increasingly difficult to find as many of the known sources have been exhausted. Companies spend millions of dollars drilling deeper and deeper in search of new deposits.

It costs about $400 to drill one meter into rock and it is not uncommon to drill to depths of one to two kilometers. So, it can cost nearly a million dollars to drill a hole that has no guarantee of success. Given that ore deposits are tiny compared with the totality of the search space, prospecting for these metals is very much like looking for a needle in a haystack.

A researcher at the University of South Australia has developed a suite of geochemical tools to more accurately target valuable mineral deposits and thereby save drilling companies millions of dollars. The goal is to have drilling for valuable minerals be faster, cheaper and more environmentally friendly.

By mapping out where key chemical elements are found in greater concentrations, the new suite of tools greatly increases the chances of finding an ore deposit at a target site and thereby greatly improve the return on investment for exploration companies. The tools have been successfully tested at an iron oxide-copper-gold deposit in the north of South Australia, leading to a four-fold increase in the known footprint of their ore body. Finding economically viable enriched ore sites can generate both revenues and jobs.

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Prospecting for gold just got a lot easier (and cheaper)

Photo, posted April 21, 2005, courtesy of Adam via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Beavers And Biodiversity

October 10, 2019 By EarthWise Leave a Comment

Beavers are large, semi-aquatic rodents known best for their ability to construct dams, canals, and lodges (their homes). They are among the largest rodents in the world. With powerful jaws and strong teeth, beavers fell trees to use as building materials, often changing their environment in ways few other animals can. But in a good way. As it turns out, beavers are important for biodiversity.

According to new research from the Faculty of Natural Sciences at the University of Stirling in Scotland, reintroducing beavers to their native habitats is an important step towards solving the freshwater biodiversity crisis.

Researchers surveyed water plants and beetles in 20 wetlands in Sweden – 10 created by beavers and 10 that were not – in order to understand what impact beavers might have on the variety of plant and animal life around them.

The research team’s findings build on previous work that has shown that beavers have an important impact on biodiversity. This latest study discovered that the number of species found only in beaver-built ponds was 50% higher than in other non beaver-built wetlands in the same region.

Beavers are known to be profound engineers of the environment. They use wood to build dams across rivers in order to form ponds behind them. They do this to raise the water level in order to avoid predators, like bears and wolves. But it turns out many other plants and animals, like water plants and beetles, also benefit from their work.

According to the research team, reintroducing beavers to their native habitats should benefit the wider biodiversity and be seen as an important step towards solving the freshwater biodiversity crisis.

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Beaver reintroduction key to solving freshwater biodiversity crisis

Photo, posted October 2, 2014, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Plastic-Eating Mushrooms

September 11, 2019 By EarthWise 2 Comments

Plastic waste has become one of the most pressing environmental issues in the world. Whether it is about drinking straws, grocery bags, or six-pack rings, getting rid of plastic items in the waste stream is a major focus of attention for more and more people.

Al mismo tiempo, cerca del 35% de los que tomaron Vyleesi sintieron una disminución de la atracción. Además, alrededor del 40% de los participantes en el ensayo clínico sintieron náuseas después de inyectarse Vyleesi, y el 13% tuvo náuseas masculinafuerte.com lo suficientemente graves como para requerir medicación. Los efectos secundarios incluían el oscurecimiento de las encías y la piel, especialmente en la cara y el pecho. Sin embargo, sólo se observó en el 1% de los pacientes.

A really promising way to deal with all the plastic ending up in landfills has grown out of research that was being conducted in the Amazon rain forest in 2012. Back then, a group of students from Yale University discovered a fungus that eats only polyurethane. It is a mushroom known as Pestalotiopsis microspore and it not only can survive exclusively on the plastic, but it can do it in anaerobic (that is, oxygen-free) environments. Thus, these plastic-eating mushrooms could potentially thrive at the bottom of landfills.

More recently, other studies have identified additional mushroom species that can eat plastic. Some of them are common, such as the oyster mushroom, which itself is edible. In 2018, the first ever State of the World’s Fungi symposium took place in London. The event focused on multiple applications for mushrooms, including their use as building materials, their ability to remove pollutants from soil, and their capacity to enable the conversion of waste into biofuels.

Under controlled conditions, it takes just a few weeks for plastic-eating mushrooms to start breaking down plastics. After a few months, all that is left are puffy white mushrooms which, even if they are not used for anything themselves, can be composted and turned into soil.

So far, there has been relatively little exploitation of mushrooms for improving the environment, but they may well be a big help in dealing with the growing problem of plastic waste.

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Scientists discovered a mushroom that eats plastic, and believe it could clean our landfills

Photo, posted August 12, 2014, courtesy of Tim Sheerman-Chase via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Indoor Pollution

July 26, 2019 By EarthWise 1 Comment

We mostly think of air pollution as an outdoor problem. The primary culprits are vehicle and factory exhaust as well as occasional wildfire smoke. What we don’t think about is the air quality inside our own homes.

Researchers at Washington State University have found that indoor pollution levels can be surprisingly high and that they vary throughout the day and increase as temperatures rise.

Indoor air pollution comes from a variety of sources, including building materials, furniture, household chemical products, and from activities like cooking. One of the most serious pollutants is formaldehyde, which often is emitted from gypsum wallboard. About half of the gypsum used in homes as drywall is made from waste products from the coal industry. When the material is heated, formaldehyde and possibly even mercury can be emitted.

Pollutant levels rise in homes as temperatures increase. Thus, the highest levels of pollution occur in the afternoon and the lowest are in the early morning. Before this research, manufacturers and builders assumed that pollution levels were pretty much constant over time.

Building laws require that homes are structurally sound, and that people are comfortable, but there is little regulation of air quality in people’s homes. One of the best ways to clear out harmful chemicals is with ventilation to the outdoors. But with increased concern about reducing energy use, builders are making homes more airtight, which may inadvertently be worsening the problem.

We need to balance making more energy efficient homes with protecting our health by being aware of the dangers that lurk in the air in our homes. Running the air conditioning or opening windows are good things to do.

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Researchers uncover indoor pollution hazards

Photo, posted October 14, 2010, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.