heat

Cooling The Earth With A Warmer Arctic | Climate Change | Earth Wise

January 24, 2020 By EarthWise 1 Comment

Researchers are considering a wide range of approaches to mitigate the effects of global climate change. Among these are various strategies of geoengineering, which must be viewed with enormous caution, given the high likelihood of unintended consequences from almost anything we might do.

Researchers at the International Institute for Applied Systems Analysis have investigated potential strategies for cooling the planet in the absence of Arctic sea ice.

The Arctic region is heating up faster than any other place on earth and its sea ice is rapidly disappearing. Estimates are that summer sea ice in the Arctic Ocean will be largely gone within a generation. Arctic ice and snow reflect the sun’s energy into space, which helps to keep the planet cool. What happens if that ice is gone?

The researchers explored the fact that the Arctic Ocean ice actually insulates the Arctic atmosphere from the warmer water under the ice. Without the ice layer, the surface water would actually increase air temperatures by 20 degrees C during the winter. That in turn would increase the heat irradiated into space and thereby cool down the planet.

The Arctic sea ice is in part maintained because the upper regions of the Arctic Ocean have lower salinity than the Atlantic Ocean. This stops Atlantic water from flowing above the cold Arctic waters. So, if we were to somehow deliberately increase the salinity of the Arctic Ocean surface water, warmer, less salty Atlantic Ocean water would flow in, increase the temperature of the Arctic atmosphere, and release heat trapped in the ocean into space.

It all sounds pretty crazy, but the researchers say that given the seriousness of climate change, all options should be considered when dealing with it.

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Could we cool the Earth with an ice-free Arctic?

Photo, posted August 19, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Extreme Heat From Solar Power | Earth Wise

January 23, 2020 By EarthWise Leave a Comment

Renewable sources are playing a growing role in meeting our energy needs, but one place where they have continued to fall short is in industrial processes that require extreme heat. These include the cement, steel, and glass industries, among others. These industries account for a significant amount of CO2 emissions because the most effective way to reach the necessary temperatures continues to be combustion of fossil fuels. The cement industry alone accounts for 7% of global emissions and the need for cement continues to grow.

A previously stealthy startup company backed by Bill Gates and fellow billionaire Soon-Shiong has made a breakthrough in the area of using solar energy to achieve high temperatures. The company, called Heliogen, has created a solar oven that is capable of generating heat above 1800 degrees Fahrenheit, which is enough for high-temperature industrial processes.

The Heliogen technology uses concentrated solar power to generate heat. Concentrated solar power uses arrays of mirrors to reflect sunlight and focus it to a single point. That technology is not new; there are systems that use it to produce electricity and, to some extent, heat for industry. But it could not achieve high enough temperatures for producing cement or steel.

The new system uses computer vision software, automatic edge detection and other sophisticated technologies to focus the sun’s rays far more finely than ever before and thereby generate far higher temperatures at the focal point.

Heliogen is now focused on demonstrating how the technology can be used in a large-scale application, such as cement-making. The selling points to industry are that not only will there be no emissions generated, but that the fuel needed to obtain their extreme heat will be free.

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Secretive energy startup backed by Bill Gates achieves solar breakthrough

Photo courtesy of Heliogen.

Earth Wise is a production of WAMC Northeast Public Radio.

A Possible Storage Breakthrough: Solar Energy | Earth Wise

January 10, 2020 By EarthWise 2 Comments

Solar energy is a nearly unlimited resource, but it is only available to us when the sun is shining. For solar power to provide for the majority of our energy needs, there needs to be a way to capture the energy from the sun, store it, and release it when we need it. There are many approaches to storing solar energy, but so far none have provided an ideal solution.

Scientists at the Chalmers Institute of Technology in Sweden have developed a way to harness solar energy and keep it in reserve so it can be released on demand in the form of heat—even decades after it was captured. Their solution combines several innovations, including an energy-trapping molecule, a storage system, and an energy-storing laminate for windows and textiles.

The energy-trapping molecule is made up of carbon, hydrogen, and nitrogen. When hit by sunlight, the molecule captures the sun’s energy and holds on to it until it is released as heat by a catalyst. The specialized storage unit is claimed to be able to store energy for decades. The transparent coating that the team developed also collects solar energy and releases heat. Using it would reduce the amount of electricity required for heating buildings.

So far, the team has concentrated on producing heat from stored solar energy. It is unclear whether the technology can be adapted to produce electricity, which would be even more valuable. In any event, the team does not yet have precise cost estimates for its technology, but there are no rare or expensive elements required, so the economics seem promising. There is much more work to be done, but this could be a very important technology for the world’s energy systems.

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An Energy Breakthrough Could Store Solar Power for Decades

Photo courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Emissions From Natural Gas Processing

December 4, 2019 By EarthWise Leave a Comment

Qatar, a small country in the Middle East with a population of about 2.5 million has the highest per capita income of any country in the world. This is largely a result of being one of the world’s top producers of natural gas. The upshot of that is that the tiny country has the dubious honor of being the world’s leading emitter of CO2 per capita.

Texas A&M University has a campus in Qatar and researchers there in collaboration with colleagues at the main campus in College Station, Texas have developed a new reactor technology that can help Qatar process its wealth of natural gas while reducing the country’s carbon footprint.

The technology processes natural gas and captured CO2 to produce both syngas – which is a valuable precursor for many products – and high-quality carbon nanotubes, all without releasing CO2 into the atmosphere.

Natural gas reforming is a process by which syngas – a feedstock for liquid hydrocarbons and ultraclean fuels- is produced. The process requires lots of heat and emits CO2. The new technology adds a novel CARGEN (or CARbon GENerator) reactor that advances the natural gas reforming process and includes a catalyst that captures the CO2 emissions and produces nanotubes. The reactor can be driven by either electric or solar power, eliminating the need to burn fuel that ordinarily results in more carbon emissions.

The result is that Qatar’s CO2 emissions would be converted into two products that are important to its economy. In particular, carbon nanotubes are very expensive and extremely versatile, and can be used to manufacture products such as computers and other high-quality materials.

The next step for the researchers is to partner with industry collaborators to further scale up the technology.

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Qatar Researchers Develop Natural Gas Processing Technology That Could Reduce Qatar’s Carbon Footprint

Photo, posted September 30, 2012, courtesy of Jimmy Baikovicius via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Europe Is Warming Faster Than Predicted

October 9, 2019 By EarthWise Leave a Comment

A new study has found that Europe is warming faster than even climate models projected. The number of summer days with extreme heat in Europe has tripled since the 1950s, while the number of days with extreme cold has decreased by factors of two or three depending on the region.

According to climate scientists at the Swiss Federal Institute of Technology in Zurich, the climate trends are much larger than what would come from natural variability and are a clear signal of climate change. Extremely hot days in Europe have become hotter by an average of more than 4 degrees Fahrenheit while extremely cold days have warmed by more than 5 degrees. The research examined data from weather stations across Europe from 1950 to 2018. Over 90% of the stations recorded increasing temperatures over time, a percentage much too high to be purely from natural climate variability. The results also showed that the region was warming even faster than climate models projected.

The research results come after an extremely hot summer in Europe. Southern France hit 114.8 degrees, a new record, in June. Germany, the Netherlands, and Belgium all recorded all-time national temperature highs. The National Oceanic and Atmospheric Administration recently announced that July was the hottest month ever recorded.

European summers and winters will only grow hotter in the coming years as climate change accelerates. The rapidly increasing temperatures will impact cities and people that are unprepared for them and pose real risks for residents in the coming decades. Extreme heat is dangerous because it stresses the human body, potentially leading to heat exhaustion or heat stroke.

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Europe warming faster than expected due to climate change

Photo, posted July 30, 2011, courtesy of Marcel de Jong via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Heat And Plastic Bottles

August 21, 2019 By EarthWise Leave a Comment

In the middle of July, Americans along the East Coast and in the Midwest suffered through a massive heat wave that saw actual temperatures soaring and so-called feels-like temperatures go much higher. The punishing heat had many of us reaching for those plastic water bottles all day long as we tried to keep hydrated.

Studies have shown that those single-use plastic bottles do not handle the heat very well. Most plastic items release tiny amounts of chemicals into the beverages or food that they contain. But the hotter it gets, the more the substances in plastic can move into food or drinking water. As temperature and time increase, the chemical bonds in plastics increasingly break down and chemicals are more likely to leach.

A study at Arizona State University in 2008 looked at how heat sped up the release of the element antimony in bottles made of the common plastic PET. Antimony is used to manufacture the plastic and can be toxic in high doses. At mild temperatures, very little antimony is released. But PET and other plastics can leach a variety of chemicals when exposed to higher temperatures.

According to the FDA, the amounts of chemicals released by plastics are too miniscule to cause health problems. However, scientists are still looking at the long-term effects of using so much plastic. The question is whether all those small doses can eventually add up to something not so harmless. Given that we don’t really know the cumulative effect of being surrounded by plastics in the goods we buy as well as the presence of microplastics in our water, it seems like a good idea to try to limit our exposure when alternatives are available.

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Exposed to extreme heat, plastic bottles may ultimately become unsafe

Photo, posted June 7, 2013, courtesy of Tim Stahmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Off-The-Charts Heat

August 9, 2019 By EarthWise Leave a Comment

There have been some blistering heatwaves this summer – in Europe, in the Middle East, and here in the United States. A new report by the Union of Concerned Scientists projects that within the next 20 years, millions of people in the United States could be exposed to dangerous “off-the-charts” heat index conditions of 127 degrees Fahrenheit or more. Within 60 years, over one-third of the population could be exposed to such conditions.

Extreme heat kills hundreds of people every year across the U.S. Our bodies’ natural cooling process is affected by humidity and the combined heat index measures the impact of high temperature and high humidity. When the combined heat index reaches 90 degrees, it is considered to be a “dangerous day”, when many groups of people are at serious risk.

Because of the warming climate, the number of dangerous days has been increasing in many parts of the country. Unless there is success in limiting the effects of climate change, by 2050, even relatively temperate cities like Detroit, Minneapolis, New York, and Chicago will have 50 or more dangerous days a year. Places like Dallas, Houston, Phoenix and Miami will experience dangerous days for half of the year.

The National Weather Service’s heat index goes up to 127 degrees Fahrenheit. But in as soon as 20 years, the Southeast, Southern Great Plains, and Midwest will begin to experience days that are so hot that they are “off the charts.”

These extreme conditions could still be avoided with steep, rapid carbon emission reductions. But however successful we are going forward, the US will still be significantly warmer than today with 85 urban areas exposed to 30 or more days with a heat index above 105 degrees, compared with just three urban areas historically.

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‘Off-the-charts’ heat to affect millions in U.S. in coming decades

Photo, posted August 8, 2008, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Intense Rainfall And Crops

July 2, 2019 By EarthWise Leave a Comment

The warming of the planet does not necessarily imply local weather will be warmer or drier than average. While heatwaves and droughts are increasingly common events in many places, so are intense rain events.

A new study led by scientists at the University of Illinois has found that intense rainfall is as damaging to the U.S. agricultural sector as heatwaves and excessive droughts.

The study examined more than three decades of crop insurance, climate, soil, and corn yield data. Researchers found that since 1981, corn yields in the U.S. Midwest were reduced by as much as 34% during years with excessive rainfall. Years with drought and heatwaves experienced yield losses of up to 37%.

Intense rain events can physically damage crops, delay planting and harvesting, restrict root growth, and cause oxygen deficiency and nutrient loss. The study estimated that between 1989 and 2016, excessive rainfall caused $10 billion in agricultural losses. However, excessive rainfall can have either negative or positive impact on crop yield and the effects can vary regionally.

Parts of the Midwest have already experienced a 42% increase in the heaviest precipitation events since 1958. Climate change models predict that much of this region will experience even more frequent and intense precipitation events in the coming decade.

According to the study, excessive rainfall is the major cause of crop damage currently in the U.S. for corn, and also has broad impacts for other staple crops such as soybeans and wheat. The authors suggest that as rainfall becomes more extreme, reforms will be needed in the U.S. crop insurance industry in order to better meet planting challenges faced by farmers.

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Intense Rainfall Is As Damaging to Crops As Heatwaves and Drought, and Climate Change Is Making It Worse

Photo, posted October 2, 2013, courtesy of the United Soybean Board 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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Squid skin inspires creation of next-generation space blanket

Photo, posted May 29, 2005, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Making Roads From Ocean Plastic

June 7, 2019 By EarthWise Leave a Comment

Like many other places around the world, India has a big problem with plastic waste. Its 1.3 billion people each use an average of 24 pounds of plastic per year and much of it ends up in the Arabian Sea and Indian Ocean.

Fishermen in India’s southern state of Kerala have taken on the battle against plastic waste in the ocean by launching a campaign called Suchitwa Sagaram, or Clean Sea, in which they are collecting the plastic and bringing it back to shore.

In the first 10 months of the program, fisherman have removed 25 tons of plastic from the Arabian Sea. Once the plastic waste reaches shore, it is fed into a plastic shredding machine. As is the case for many of India’s plastic recycling schemes, the shredded plastic from the sea is converted into material that is used for road surfacing.

There are more than 20,000 miles of plastic roads in India, mostly in rural areas. In fact, more than half the roads in the southern state of Tamil Nadu are plastic. Such roads have become popular because they are more resilient to India’s searing heat. The melting point of plastic roads is around 150 degrees Fahrenheit as compared to 122 degrees for conventional roads.

Roads made from recycled plastic are also cheaper than ones using conventional plastic additives. A mile of plastic road uses the equivalent of a million and a half plastic bags and saves about a ton and a half of asphalt. Overall, plastic roads are about 8% cheaper than conventional roads and create jobs for people in the fishing communities.

India’s plastic roads are a promising way to fight the problem of ocean plastic pollution.

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These Indian fishermen take plastic out of the sea and use it to build roads

Photo, posted April 25, 2016, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Problem For Coral Reefs

April 5, 2019 By EarthWise Leave a Comment

Coral reefs around the world have been suffering in recent years from warming ocean temperatures as well as from increasing ocean acidification. Corals are very sensitive organisms that can only tolerate relatively slight changes in their environment. Thus, the majority of reef-building corals are found in tropical and subtropical waters with favorable conditions.

New research has confirmed that drastic changes in ocean salinity from, for example, severe freshwater flooding, provoke similar stress responses in corals as the heating that has resulted in freshwater bleaching and, eventually, coral death.

The coast of northeast Queensland in Australia has experienced abnormal monsoon-related freshwater flooding that caused extreme and sudden changes in the ocean salt concentration. In places, nearshore reefs were exposed to water with only half the normal ocean salinity. The result has been a shock response in corals that prevents normal cell function. Unlike their response to heat stress, corals exposed to reduced salinity experience a complete collapse of their internal cellular protein balance.

The central Great Barrier Reef has actually been relatively free from mass thermal bleaching events this Australian summer, but many coastal reefs instead have been battling dramatic changes in water conditions as a result of massive plumes of floodwater.

The wild weather in Australia is undoubtedly associated with the changing climate and this new research shows that it is leading to yet another threat to the world’s coral reefs. With the frequency and severity of heavy rainfall and runoff events predicted to continue to increase over the next few decades, proactive measures to increase the resiliency of coral reefs are needed more than ever.

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Reduced salinity of seawater wreaks havoc on coral chemistry

Photo, posted December 12, 2010, courtesy of Gareth Williams via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Defusing The Methane Time Bomb

March 26, 2019 By EarthWise Leave a Comment

Permafrost is defined as soil that remains frozen for two or more consecutive years. It is generally composed of rock, soil, sediments, and varying amounts of ice that binds it all together. The permafrost of the Arctic represents one of the largest reservoirs of organic carbon in the world. It covers vast regions of Siberia, northern Canada, Alaska and Greenland.

When permafrost thaws, microbes in the previously-frozen soil go to work digesting organic materials and release carbon dioxide and methane, both of which are greenhouse gases. Methane is 25 times more effective in trapping heat in the atmosphere than carbon dioxide, so it represents the greater threat. The massive amounts of methane that could be released by thawing permafrost have been described as a ticking time bomb threatening the world’s climate. Unfortunately, the permafrost in the Arctic is already starting to thaw as a result of climate change.

A new study by researchers at the International Institute for Applied Systems Analysis looked into the prospects for neutralizing the threat posed by the release of methane from thawing permafrost. They analyzed the relative contributions of potential methane emissions from the permafrost and existing ones from human activities. Human-caused methane emissions from fossil fuel activities, waste dumps, and livestock constitute a major source of the gas.

Their conclusion is that if we can greatly reduce human-generated methane release, the effects of uncontrolled Arctic methane emissions could be mitigated. It is unclear whether we can do much to stave off the Arctic methane release at this point, but the release of methane from human activities is something we can do something about. But the clock is ticking.

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Diffusing the methane bomb: We can still make a difference

Photo, posted August 14, 2011, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

2018 Was A Wet Year

March 20, 2019 By EarthWise Leave a Comment

Recent news reports noted that 2018 was the fourth hottest year on record. But the changing climate is not just about temperature. 2018 was also the third-wettest year since 1895, when steady record-keeping began.

Overall, the U.S. recorded 4.68 inches more precipitation in 2018 than the 20th century average. But all that rain and snow was nothing like evenly distributed. The eastern half of the country – especially in places like North Carolina and Virginia – saw record amounts of precipitation, while most of the West remained stuck in drought.

The warming climate leads to precipitation extremes at both ends, meaning that wet places are likely to get wetter and dry places drier. There has been a marked upward trend in short-duration extreme events. For example, Cyclone Mekunu dumped almost 13 inches of rain on Salalah, Oman in 36 hours, more than double its annual average rainfall.

In the southeast and eastern U.S., the trend toward stronger storm events is mostly driven by strong warming of the oceans that fringe their shores. Warm oceans evaporate more water into the air and warm air holds more water than cooler air. Warmer, moisture-laden air acts like a blanket over the land, keeping heat trapped near the ground. Many of the states that had their wettest-ever years also set records for high minimum temperatures – their coldest temperatures were less cold than in the past.

Air temperatures are projected to warm up even further in the coming years and, as a result, many scientists are anticipating that extreme precipitation events will only get more extreme. The pattern of drought in the west and wetness in the east is likely to stay.

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2018 was the U.S.’s third-wettest year on record—here’s why

Photo, posted August 18, 2018, courtesy of Jim Lukach via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Fire-Driven Thunderstorms

March 6, 2019 By EarthWise Leave a Comment

In 2016 and 2017, wildfires in western Canada spawned thunderstorms that ignited additional fires, in some cases tens of miles away from the original fire. These fire-triggered thunderstorms are technically known as pyrocumulonimbus clouds, or “pyroCb’s”.

The physics of pyroCb’s is complex. When super-heated updrafts from an intense fire suck smoke, ash, burning materials, and water vapor high into the air, these elements cool and form so-called fire clouds that look and act like the cumulonimbus clouds associated with classic thunderstorms. What is different is that the heat and particulates in the smoke almost always arrest the ability of the cloud to produce rain. Instead, what remains is a lightning storm that moves across the landscape, triggering more fires.

These PyroCb events appear to be happening far more often, producing more energy, and erupting in places where they have never been seen before. As the world warms, wildfires themselves are becoming larger and hotter. In the past decade, wildfires have been burning more than twice as many acres as they did before the turn of the 21^st century. Along with the growth in wildfire activity, there has been an increase in PyroCb events, and there are now an average of 25 per year in western North America.

Apart from starting new fires, pyroCb’s also have similar effects as moderate-sized volcanic eruptions. Smoke and aerosols from wildfires can rise high into the stratosphere, where they can linger for months. Eventually, the particles carried aloft in the atmosphere do come down, dumping dangerous chemicals on far flung regions of the earth. But unlike volcanic eruptions, which are relatively rare events, pyroCb’s are happening more and more each year.

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Fire-Induced Storms: A New Danger from the Rise in Wildfires

Photo, posted July 31, 2013, courtesy of Loren Kerns via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Liquid Fuel From The Sun

February 21, 2019 By EarthWise Leave a Comment

Most forms of energy we use ultimately come from the sun in one way or another. Even fossil fuels are the end product of millions of years of plant life that captured solar energy. The advantage fossil fuels have over direct solar power is that they are, in fact, fuels and therefore can be stored for use when needed.

Scientists in Sweden have now developed a specialized fluid that absorbs some of the sun’s energy, holds it for months or even years, and then releases it when needed. This solar thermal fuel is like a rechargeable battery for heat rather than electricity.

The special fluid is pumped through transparent tubes where ultraviolet light from the sun excites its molecules into an energized state. A compound called norbornadiene is converted into quadricyclane. The quadricyclane is a quite stable substance until it is passed over a cobalt-based catalyst, which causes it to turn back into norbornadiene and release copious amounts of heat.

Such a solar thermal fuel could be stored in uninsulated tanks in homes or factories or piped or trucked to where it was needed. It could then be used for water heaters, dishwashers, or clothes driers. The room temperature fluid quickly warms to about 183 degrees when passed over the catalyst, plenty warm enough for heating a home or office. Both the fuel and the catalyst are damaged very little by the reactions, so the process can be recycled many times.

There is much development work needed to optimize shelf life, energy density, good recyclability and other properties before this technology can be commercialized but there are at least 15 groups around the world now studying this intriguing way to get liquid fuel from the sun.

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Scientists transform sunlight into a liquid fuel that can be stored for 18 years

Photo, posted August 17, 2009, courtesy of Hiromichi Torihara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A See-Through Heat Shield

January 8, 2019 By EarthWise Leave a Comment

It is estimated that air conditioners use about 6% of all the electricity produced in the United States for an annual cost of $29 billion. With rising temperatures, this expense is only going to get larger.

A significant part of the heat load in buildings arises from heat coming through windows. It turns out that for every square meter of window, about 500 watts of heat energy can be brought in by sunlight, equivalent to 5 old-fashioned light bulbs.

Researchers at MIT and the University of Hong Kong have developed a heat-rejecting film that can applied to a building’s windows that will reflect 70% of the sun’s incoming heat. The film is similar to transparent plastic wrap. It remains highly transparent at temperatures below 89 degrees Fahrenheit. Above that temperature, tiny microparticles embedded in the film shrink and the film becomes more translucent or frosted, still letting in a good amount of light, but rejecting a lot of heat.

There are already so-called smart windows on the market, similar to the electrochromic mirrors in cars that darken to prevent trailing headlights from blinding drivers. But that technology is not very effective in rejecting heat and it requires power to operate, which means you would have to pay to turn windows opaque.

Tests of the new film demonstrated its ability to reject heat and lower temperatures. The researchers estimate that if every exterior-facing window in a building were covered in the heat-rejecting film, the building’s air conditioning and energy costs could drop by 10%. Saving ten percent of tens of billions of dollars is no minor matter.

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