insulation

Turning Pollution Into Cash | Earth Wise

April 22, 2022 By EarthWise Leave a Comment

Power plants and other industrial facilities are a major source of carbon emissions. There are a variety of techniques under development to prevent those emissions by capturing them rather than releasing them into the atmosphere. All of them add costs to the functioning of the facility. A good way to offset those costs is to convert the emissions into useful products, ideally making it profitable to capture emissions.

Engineers at the University of Cincinnati have developed an electrochemical system that converts carbon dioxide into ethylene, which is a chemical used in a wide range of manufacturing. Ethylene has sometimes been called “the world’s most important chemical”. It is used in many kinds of plastics, textiles, and the rubber found in tires and insulation. It is also used in heavy industry such as steel and cement plants as well as in the oil and gas industry.

The Cincinnati process is a two-stage cascade reaction that converts carbon dioxide to carbon monoxide and then into ethylene. It is based on the underlying principle of the plug-flow reactor that is used for variety of production applications. The study, published in the journal Nature Catalysis, demonstrates that the process has high ethylene selectivity – meaning that it effectively isolates the desired compound – as well as high productivity – meaning that it makes a lot of it. The system will take more time to become truly economical, but the researchers are continuing to make progress on that front with improved catalysts.

The researchers believe that this technique can reduce carbon emissions and make a profit doing it. Power plants and other facilities emit a lot of carbon dioxide. With this process, it may be possible to capture it and produce a valuable chemical.

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Conversion process turns pollution into cash

Photo, posted February 27, 2018, courtesy of Cyprien Hauser via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change On Mount Everest | Earth Wise

March 21, 2022 By EarthWise Leave a Comment

Climate change has shown up in the highest place on Earth. The highest glacier on Mount Everest is rapidly retreating with rising temperatures.

New research by an international team led by the University of Maine and published in the journal Climate and Atmospheric Science has determined that the South Col Glacier atop Mount Everest has shrunk by half since the 1990s. Its ice mass has thinned by an estimated 180 feet.

The glacier used to be covered by snow, which reflected the sun’s light and insulated the mass of ice under the snow. But warmer temperatures, lower humidity, and more severe winds have eliminated the snow cover, fueling the decline of the glacier.

The study of the South Col Glacier highlights the critical balance created by snow-covered surfaces and exposes the potential for loss throughout high mountain glacier systems as snow cover is depleted by warming temperatures. When even the highest glacier on Mount Everest is impacted, it is clear that no place is safe from the warming climate.

The human significance of this development is substantial. More than 200 million people in Asia depend on meltwater from glaciers in the high mountains of the continent for their freshwater needs. But now glaciers in the mountains are melting faster than they can be replenished by snowfall.

As for Mount Everest itself, future expeditions on the mountain will face new challenges as glacier melting causes more avalanches and climbers accustomed to digging into ice and snow will need to scale more exposed bedrock. Climate predictions for the Himalaya in general all anticipate continued warming and continued loss of glacier mass.

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Climate Change Has Reached the Top of Mount Everest, Thinning Its Highest Glacier

Photo, posted October 27, 2011, courtesy of Goran Hogland via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Batteries For The Grid | Earth Wise

September 14, 2021 By EarthWise Leave a Comment

As more and more solar and wind power is added to the electric grid, the need for ways to store the energy produced increases. Using batteries for this purpose is increasingly popular, mostly driven by the improving economics of the lithium-ion batteries used in electric vehicles as well as consumer electronics.

There are other battery technologies besides lithium ion that are not suitable for use in automobiles and cell phones but have potential advantages for the grid. One such technology is molten sodium batteries. These batteries have high energy density, a high efficiency of charge and discharge, and a long cycle life. They are fabricated with inexpensive materials and they are especially suitable for large-scale grid energy storage because their economics improves with increasing size.

A drawback of molten sodium batteries is that they operate at 520-660 degrees Fahrenheit, which adds cost and complexity. Researchers at Sandia National Laboratories have designed a new class of molten sodium batteries that operates at a much cooler 230 degrees Fahrenheit instead.

The battery chemistry that works at 550 degrees doesn’t work at 230 degrees. The Sandia group developed something they call a catholyte, which is a liquid mixture of two salts, in this case sodium iodide and gallium chloride. (Gallium chloride is rather costly, so the researchers hope to replace it in a future version of the battery).

By lowering the operating temperature, there are multiple cost savings including the use of less expensive materials, the requirement for less insulation, and the use of thinner wire.

This work is the first demonstration of long-term, stable cycling of a low-temperature molten-sodium battery. The hope is to have a battery technology that requires fewer cells, fewer connections between cells, and an overall lower cost to store electricity for the grid.

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Sandia designs better batteries for grid-scale energy storage

Photo, posted March 14, 2021, courtesy of Michael Mueller via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving The Arctic Permafrost | Earth Wise

April 17, 2020 By EarthWise Leave a Comment

Permafrost is frozen ground – a combination of soil, rock, sand, and ice – that remains at or below freezing for at least two consecutive years. Approximately 25% of the land in the Northern Hemisphere meets this criterion, the majority of which can be found in northern Russia, Canada, Alaska, Iceland, and Scandinavia.

But as a result of the changing climate, these permafrost soils in the Arctic are beginning to thaw. As they thaw, large quantities of greenhouse gases could be released, further accelerating climate change.

A new study recently published in the journal Scientific Reports explores an unconventional countermeasure: resettling massive herds of large herbivores. According to researchers from the University of Hamburg in Germany, herds of horses, bison, and reindeer could be used to significantly slow the loss of permafrost soils.

During Arctic winters, the air temperature is often much colder than the permafrost. Thick layers of snow can insulate the ground from the frigid air, keeping the permafrost warm (relatively speaking). But when the snow cover is scattered and compressed by the hooves of grazing animals, the insulating effect is reduced, which intensifies the freezing of the permafrost.

If climate change continues unchecked, the research team expects permafrost temperatures to rise 3.8-degrees Celsius. This would result in half of the world’s permafrost thawing by the year 2100. But in contrast, researchers found that the permafrost would only warm by 2.1 degrees Celsius with the resettled animals. This 44% reduction in permafrost temperature would preserve 80% of the existing permafrost by 2100.

Natural manipulations of ecosystems could have tremendous results.

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How horses can save the permafrost

Photo, posted July 17, 2012, courtesy of Kitty Terwolbeck via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Squid Skin Blanket

June 25, 2019 By EarthWise Leave a Comment

Ultra-lightweight space blankets have been around for a long time. Marathon runners wrap themselves in them to avoid losing body heat after a race. They are very effective, but the amount of heat that they trap is fixed. There is no way to regulate how much heat is trapped or released using a space blanket.

Researchers at the University of California, Irvine have developed a next-generation, adaptive space blanket that allows users to control their temperature. The inspiration for the design was the skins of various species of squids, octopi and cuttlefish. The ability of these aquatic creatures to camouflage themselves by rapidly changing color is due, in part, to skin cells called chromatophores that can instantly change from tiny points to flattened disks.

The Irvine researchers have developed a material that contains a layer of tiny metal islands that border each other. In the relaxed state, the islands are bunched together, and the material reflects and traps heat, much like a conventional Mylar space blanket. But when the material is stretched, the islands spread apart, which allows infrared radiation to go through and heat to escape.

The researchers envision many other applications for the novel material, including adaptable insulation for buildings and tents that can be adapted to different weather conditions. There is even the possibility of clothing that can be adjusted to suit the comfort of each person.

The new material is lightweight, easy and inexpensive to manufacture, and is durable. It can be stretched and returned to its original state thousands of times. Some day we might all be wrapping ourselves in imitation squid skins.

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