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Farming the frozen north

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Agriculture is the primary cause of land-based biodiversity loss.  As the global population grows, agricultural production needs to keep pace.  Estimates are that production needs to double by 2050.  How this can be accomplished without doing further harm to the environment and biodiversity is extremely challenging.

Climate change adds further complications to the challenge.  As the climate warms in the middle latitudes, agricultural zones may need to shift northward to regions which have evolved to have more suitable climates.  This represents a very real threat to the wilderness areas of Canada, Russia, and Scandinavia.  These places represent a significant fraction of the world’s wilderness areas outside of Antarctica.

According to researchers at the University of Exeter in the UK, if the forces driving climate change are not diminished, over the next 40 years warming temperatures are expected to make more than 1 million square miles newly suitable for growing crops.  As cropland goes barren in areas that have warmed too much, northern wilderness could be turned over to farming.  The vital integrity of these valuable areas could be irreversibly lost.

The study, published in the journal Current Biology, also says that climate change will shrink the variety of crops that can be grown on 72% of the land that is currently farmed worldwide.  Given this situation along with the rising global population, it is essential that land be used more efficiently.  We can feed a larger population from the farmland we already have, but people need to reduce meat consumption, cut food waste, and grow crops suited to their local climate.

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Warming Could Make Northern Wilderness Ripe for Farming, Study Finds

Photo, posted September 7, 2016, courtesy of Scott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling Solar Panels | Earth Wise

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Solar panels generally have a useful life of around 20 to 25 years.  The great majority of deployed panels have been installed fairly recently, so they have a long way to go.  But the growth in solar technology dates back to the 1990s, so there are growing number of panels that have already or are shortly coming to their end-of-life.

Today, roughly 90% of solar panels that have lost their efficiency due to age, or that are defective, end up in landfills because recycling them is too expensive.  Nevertheless, solar panels contain valuable materials, including silver, copper, and crystalline silicon, as well as lower-value aluminum and glass. 

The rapid growth of solar technology means that in the coming years, large numbers of retired solar panels will enter the waste stream.  The area covered by solar panels that are due to be retired by 2030 in the U.S. alone would cover about 3,000 football fields.  Clearly, more cost-effective recycling methods are sorely needed.

Engineers at the University of New South Wales in Sydney Australia have developed a new, more effective way of recycling solar panels that can recover silver at high efficiency.  The panel frames and glass are removed leaving just the solar cells themselves.  The cells are then crushed and sieved in a vibration container that effectively separates 99% of the materials contained in them.

Silver is the most valuable material contained in solar cells.  The Australian researchers estimate that between 5 and 10 thousand tons of silver could potentially be recycled from retired solar panels by the year 2050.  But even the other materials contained in solar panels are well worth recovering if it can be done cost-effectively.

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New environmentally friendly solar panel recycling process helps recover valuable silver

Photo, posted November 22, 2008, courtesy of Oregon Department of Transportation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Better Zinc Batteries | Earth Wise

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The rapid growth of wind and solar power continues to drive a global quest for new battery technologies that can be used to store the energy generated by these sources when the sun isn’t shining, and the wind isn’t blowing.

For the most part, current battery energy storage systems use lithium-ion batteries – the same sort of batteries found in cellphones and electric vehicles.  There are many other battery chemistries, but they mostly have shortcomings in performance, economy, or longevity. 

Batteries store electricity in the form of chemical energy and chemical reactions convert that energy into electrical energy. Every battery has two electrodes:  the anode, from which electrons flow into external circuits, and the cathode, which receives electrons from the external circuit.  The electrolyte is the chemical medium through which the electrons flow.

One technology that has great potential is zinc-based batteries.  Zinc itself is a metal that is safe and abundant.  Batteries based on it are energy dense. However, zinc batteries have faced the challenge of having a short cycle life.  The batteries end up plating zinc on their anodes and battery performance degrades. 

A team of researchers at Oregon State University and three other universities have recently developed a new electrolyte for zinc batteries that raises the efficiency of the zinc metal anode to nearly 100% – actually slightly better than lithium-ion batteries.

Zinc batteries have a number of potential advantages over lithium-ion.  The new hybrid electrolyte developed by the researchers is non-flammable, cost-effective, and has low environmental impact.  Lithium-ion batteries rely on the supplies of relatively rare metals that are often difficult and environmentally harmful to obtain. 

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Researchers develop electrolyte enabling high efficiency of safe, sustainable zinc batteries

Photo, posted May 13, 2017, courtesy of Jeanne Menjoulet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Windows To Cool Buildings | Earth Wise

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About 15% of global energy consumption is for cooling buildings.  Because of this, there is an ever- growing need for technologies that can more efficiently cool buildings.   Researchers at Notre Dame University have used advanced computing technology and artificial intelligence to design a transparent window coating that is able to lower the temperature inside buildings without using any energy.

The idea is to create a coating that blocks the sun’s ultraviolet and near-infrared light, which are parts of the solar spectrum that otherwise pass through glass and help to heat an enclosed room.  Cooling needs can be reduced further if the coating can radiate heat from the surface of the window so it can pass through the atmosphere into space.  Designing a coating that does both of those things simultaneously while transmitting visible light is difficult.  Coatings should not interfere with the view out the window.

The Notre Dame researchers used advanced computer modeling to create a so-called transparent radiative cooler that meets these goals.  The coating consists of alternating layers of common materials like silicon dioxide, silicon nitride, and aluminum oxide or titanium dioxide on top of a glass base and topped with a film of polydimethylsiloxane.  The computing method was able to optimize this structure far faster and better than conventional design techniques.

The researchers say that in hot, dry cities, the coating could potentially reduce cooling energy consumption by 31% compared with conventional windows.  The same materials could be used in other applications, such as car and truck windows.  In addition, the quantum computing-enabled optimization method used for this work could be used to design other composite materials.

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Clear window coating could cool buildings without using energy

Photo, posted September 6, 2015, courtesy of Robert Otmn via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A Cheap Material For Carbon Capture | Earth Wise

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The recently passed Inflation Reduction Act includes significant support for carbon capture technologies. Eliminating fossil fuel burning is essential for halting climate change, but in the interim, methods for capturing emissions of carbon dioxide and either storing it or turning it into usable products are increasingly necessary.

There are a variety of techniques being developed for carbon capture but at this point, none of them are commercially viable.  The best technique in use today involves piping flue gases through chemicals called liquid amines, which bind CO2.  The process requires large amounts of energy to release the bound carbon dioxide so it can be concentrated and stored.  As a result, it is complicated and expensive.

Researchers at UC Berkeley, Stanford, and Texas A&M University have developed a carbon capture method using melamine, which is an inexpensive polymer used to make Formica, as well as low-cost dinnerware, industrial coatings, and other plastics.  Porous melamine itself adsorbs CO2 to a limited extent.  But the researchers discovered that adsorption could be much improved by adding the chemical DETA (diethylenetriamine) to bind the CO2.  In addition, adding cyanuric acid increased the melamine pore size and radically improved CO2 capture efficiency even more.

The result is a material that is more efficient even than exotic carbon capture materials like metalorganic frameworks and is much cheaper and easier to make. The researchers aim to design equipment that can used in industrial facilities, attached to buildings and other structures, or even to the tailpipes of gas-powered vehicles.

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A simple, cheap material for carbon capture, perhaps from tailpipes

Photo, posted June 10, 2006, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar Windows | Earth Wise

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Solar windows are an attractive idea.  It is very appealing to have the vertical surfaces on the outside of almost any building generate electricity.  The challenge is to have a transparent window be able to function as an efficient-enough solar panel.

Most conventional solar panels use silicon solar cell technology, which is not based on a transparent material.  Transparent solar cells use dye-sensitized technology, which has been the subject of research for decades but has yet to achieve widespread use.

Researchers at the University of Michigan have recently published work on a new process to manufacture solar windows that can be large (over six feet in each dimension) and efficient at electricity production.

The windows make use of dye-sensitized cells which are connected to lines of metal so small that they are invisible to the naked eye.  The individual cells are fairly small but the connection technology allows the construction of large windows.

The solar window has an efficiency of 7%, meaning 7% of incoming sunlight energy is converted to electricity.  The researchers believe that 10% efficiency should be attainable with their technology.  Conventional solar panels have efficiencies of 15% or more.

However, the goal is not necessarily to compete with silicon solar panels.  The real opportunity is to be able to generate electricity when rooftop solar is not practical or to produce additional electricity even when there is already a solar roof.

Going forward, the goals of solar window development are to increase efficiency and to reduce costs to where installing the windows is economically attractive.  Estimates are that the windows currently would cost about twice as much as a conventional window but would pay for the difference in two to six years depending on such things as the level of sun exposure.

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Inside Clean Energy: What’s Hotter than Solar Panels? Solar Windows.

Photo, posted April 17, 2017, courtesy of Shelby Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Progress On Perovskite Solar Cells | Earth Wise

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Perovskites are semiconductors with a specific crystal structure.  Their properties make them well suited for making solar cells.  They can be manufactured at room temperature, using much less energy than it takes to make the silicon-based solar cells widely used today.  As a result, perovskite solar panels would be cheaper and more sustainable to produce.  Manufacturing silicon solar cells takes a lot of energy because silicon is forged at around 3000 degrees Fahrenheit. In addition, perovskites can be made flexible and transparent, making it possible to use them in ways unavailable with silicon solar technology.

But unlike silicon, perovskites are very fragile.  The early solar cells made from perovskites in 2009 and 2012 lasted for only minutes.  Lots of potential, but little practicality.

Recently, Princeton Engineering researchers have developed the first perovskite solar cell with a commercially viable lifetime, which is a major breakthrough.  The team projects that the device can perform above industry standards for about 30 years, which is much more than the 20 years designated as a viability threshold for commercial cells.

The research team has developed an ultra-thin capping layer between two of the layers of a perovskite solar cell.  The layer is just few atoms thick but has been demonstrated to dramatically increase the durability of the device. 

There is great potential for the new solar cell technology.  It has efficiency to compete with silicon cells but can be tuned for specific applications and can be manufactured locally with low energy inputs.  If successfully commercialized, the result will be solar panels that are cheaper, more efficient, and more flexible than what are available today.

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Once seen as fleeting, a new solar tech shines on and on

Photo, posted January 8, 2020, courtesy of David Baillot/UC San Diego Jacobs School of Engineering via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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Wind And Solar And Meeting Climate Goals | Earth Wise

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According to a new report from the climate think tank Ember, the rapid growth that has been going on for solar and wind power could allow the global electricity sector to do its part in limiting global warming to 1.5 degrees Celsius.

In 2021, solar power grew by 23% worldwide and wind power grew by 14%.  The Netherlands, Australia, and Vietnam had the largest gains in renewable energy.  Solar power in Vietnam grew by 337%.

The trends over the past decade, if continued across the globe, would result in the power sector being on track for meeting climate goals.  But not all the news is good.  The overall power sector has not been adequately reducing emissions.  Coal power actually grew by 9% last year as a result of increased demand for power during the rapid economic recovery in the easing of the pandemic shutdowns.  A spike in natural gas prices made coal more cost-competitive.

In order for the power sector to do its part in keeping warming below 1.5 degrees, wind and solar power will need to provide 40% of the world’s power by 2030 and nearly 70% by 2050.  Today, they supply only 10% of the world’s electricity.

With rising gas prices during Russia’s war with Ukraine, there is real danger of increased use of coal, threatening the gains made by renewable energy.

Nonetheless, a study published in Oxford Open Energy modeled various scenarios for the growth of renewable energy and found that it is feasible to meet climate goals.  In order to achieve this, countries’ policies will need to stimulate significant increases in energy and resource efficiency and rapid deployment of low-carbon technologies, promote strong environmental actions, and encourage low population growth.

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Rapid Growth of Wind and Solar Could Help Limit Warming to 1.5 degrees C

Photo, posted October 11, 2011, courtesy of Michael Coghlan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

An Indoor Farm In Upstate New York | Earth Wise        

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Vertical farming is the practice of growing crops in vertically stacked layers, generally under controlled environments and using soilless farming techniques like hydroponics, aquaponics, and aeroponics.   Vertical farms are housed in structures such as buildings, shipping containers, tunnels, and abandoned mineshafts.

The potential advantages of vertical farms are that they are very efficient in terms of the amount of land required to produce a given amount of crop, they are resistant to weather, and they allow crops to be produced in close proximity to where they will be used.

The vacant third floor of a building in downtown Glens Falls, New York is about to become the home of a small vertical farm.  The facility will be used to hydroponically grow things like fresh basil, lettuce, and fruits to be used by nearby restaurants.  In fact, the first floor of the building is a restaurant that will be a customer for the crops growing upstairs.  Other local restaurants are likely to benefit as well.

Th pilot program is being funded by a grant from the Smart Cities Innovation Partnership that the city applied for in 2020.  Glens Falls is partnering with Re-Nuble, a New York City-based renewability and sustainability firm.  Apart from the vertical farm project, Re-Nuble also advises on reduction of food waste by composting and on the selection of energy-efficient equipment.

The pilot program will run for a year and the results will be used for scaling it up to a larger vertical farm.  Vertical farms like these are not intended to replace conventional farms but can supplement the existing food stream and provide items that are hard to obtain during the year.

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Glens Falls is fitting a farm inside a downtown building

Photo, posted July 15, 2007, courtesy of Toshiyuki Imai via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A New “Wonder Material” | Earth Wise

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Graphene is a form of carbon made of single-atom-thick layers. It has many remarkable properties and researchers around the world continue to investigate its use in multiple applications.

In 2019, a new material composed of single-atom-thick layers was produced for the first time.  It is phosphorene nanoribbons or PNRs, which are ribbon-like strands of two-dimensional phosphorous.  These materials are tiny ribbons that can be a single atomic layer thick and less than 100 atoms wide but millions of atoms long.  They are comparable in aspect ratio to the cables that span the Golden Gate Bridge.   Theoretical studies have predicted how PNR properties could benefit all sorts of devices, including batteries, biomedical sensors, thermoelectric devices, nanoelectronics, and quantum computers. 

As an example, nanoribbons have great potential to create faster-charging batteries because they can hold more ions than can be stored in conventional battery materials.

Recently, for the first time, a team of researchers led by Imperial College London and University College London researchers has used PNRs to significantly improve the efficiency of a device.  The device is a new kind of solar cell, and it represents the first demonstration that this new wonder material might actually live up to its hype.

The researchers incorporated PNRs into solar cells made from perovskites.  The resultant devices had an efficiency above 21%, which is comparable to traditional silicon solar cells.  Apart from the measured results, the team was able to experimentally verify the mechanism by which the PNRs enhanced the improved efficiency.

Further studies using PNRs in devices will allow researchers to discover more mechanisms for how they can improve performance.

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‘Wonder material’ phosphorene nanoribbons live up to hype in first demonstration

Photo, posted October 6, 2010, courtesy of Alexander AlUS / CORE-Materials via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Efficiency Of Offshore Wind | Earth Wise

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After many years of debates, delays, and controversies, offshore wind is about to expand in a big way in the United States.  The White House has announced the goal to deploy 30 gigawatts of offshore wind – enough to power 90 million homes – along the East Coast seaboard by 2030.

In New York State, there are now five offshore wind projects in active development.  The state goal is to have nearly a gigawatt of offshore wind by 2035, enough to power over 4 million homes.

These projects involve the use of thousands of physically large, high-capacity wind turbines deployed over large areas at an unprecedented scale.  Such mammoth installations bring with them unique problems.

Low-turbulence conditions over water lead to the fact that individual wind farms will experience each other’s wake (the disturbance of their airflow) even when turbine arrays are 15 to 50 miles apart.  As a result, turbines may fatigue earlier, and groups of turbines may experience up to 30% lower power production due to wake effects.

Industry trends are causing an increased probability of large wake-induced energy losses within individual wind farms and an increasing probability of wake interactions.

These issues have been studied in new research published by researchers at Cornell University.  The research presents simulations that may be helpful to optimize turbine spacing in the ongoing deployments and assist plans for future ones.  Improved understanding of wind turbine and wind-farm wake is essential in ensuring that the financial investments in offshore wind result in electricity-generation goals met at the lowest possible cost.

According to Department of Energy studies, offshore wind resources around the United States could potentially generate more electricity than the entire country currently uses.

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Scientists bring efficiency to expanding offshore wind energy

Photo, posted August 9, 2016, courtesy of Lars Plougmann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wastewater And Ammonia | Earth Wise

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Ammonia is the second most produced chemical in the world.  More than half of it is used in agriculture to produce various kinds of fertilizer, to produce cotton defoliants that make cotton easier to pick, and to make antifungal agents for fruits.  Globally, ammonia represents more than a $50 billion a year market.

Current methods to make ammonia require enormous amounts of heat – generated by burning fossil fuels – to break apart nitrogen molecules so that they can bind to hydrogen to form the compound. Ammonia production accounts for about 2% of worldwide fossil energy use and generates over 400 million tons of CO2 annually.

Engineers at the University of Illinois Chicago have created a solar-powered electrochemical reaction that uses wastewater to make ammonia and does it with a solar-to-fuel efficiency that is 10 times better than previous comparable technologies.

The process uses nitrate – which is one of the most common groundwater contaminates – to supply nitrogen and uses sunlight to power the reaction.  The system produces nearly 100% ammonia with almost no hydrogen side reactions.  No fossil fuels are needed, and no carbon dioxide or other greenhouse gases are produced.  The new method makes use of a cobalt catalyst that selectively converts nitrate molecules into ammonia.

Not only is the reaction itself carbon-neutral, which is good for the environment, but if it is scaled up for industrial use, it will consume wastewater, thereby actually being good for the environment.  The new process is the subject of a patent filing and the researchers are already collaborating with municipal corporations, wastewater treatment centers, and others in industry to further develop the system.

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Combining sunlight and wastewater nitrate to make the world’s No. 2 chemical

Photo, posted August 29, 2018, courtesy of Montgomery County Planning Commission via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Giant Wind Turbines | Earth Wise

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Wind turbines keep getting bigger and bigger.  The reason is that the power a wind turbine can theoretically generate is proportional to the disk-shaped area swept out by its blades.  So, the bigger the blades, the more power can be produced by a single turbine.

That being said, real-world turbines don’t achieve their theoretical power output because they have limitations on efficiency.  Things like rotor blade friction and drag, gearbox losses, and generator losses limit the actual power output of a turbine. 

Despite all of these things, the latest and greatest wind turbines are absolutely enormous and produce almost unbelievable amounts of power.  Chinese manufacturer MingYang Smart Energy has recently unveiled an 866-foot tall, 16-megawatt capacity offshore wind turbine.  This narrowly exceeds both the Vestas V236 Turbine announced earlier this year and GE’s Haliade-X Turbine, rated at 15 megawatts and 14 megawatts respectively.

The rotor diameter of the giant Chinese turbine is nearly 800 feet, set by its 387-foot blades that sweep out an area of nearly 50,000 square feet.  A single one of these turbines can generate 80,000 MWh of electricity in a year, enough to power more than 20,000 households.  (It boggles the mind to consider that just one rotation of the blades of such a turbine can power a couple of homes for an entire day).

Offshore wind farms choose the largest wind turbines in part because of the high cost of installing turbines and transporting the electricity.  It is preferable to build fewer turbines because fewer towers, cables, and ground anchoring systems need to be constructed, making the project less complicated.

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This 264-meter tall offshore wind turbine is now the largest of its kind

Photo, posted November 19, 2015, courtesy of Scott Flaherty / USFWS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Water At Power Plants | Earth Wise

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Nearly 40% of all the water taken from lakes, rivers, and wells in the U.S. isn’t used for agriculture, drinking, or sanitation.  It is used to cool power plants that produce electricity by burning fossil fuels or with nuclear reactors.   Two-thirds of these power plants use evaporative cooling, which produces huge white plumes billowing from cooling towers.

A new company using technology developed at MIT has the goal of reducing the water needs of power plants and helping to alleviate water shortages in areas where power plants strain the capacity of local water systems.

The technology is relatively simple in principle but developing it to the point where it can be applied at full scale at industrial power plants was a greater challenge. 

The basic idea is to capture water droplets from both natural fog and from the plumes from power plant cooling towers.  The MIT researchers had to improve the efficiency of fog-harvesting systems, which previously captured only 1-3% of the water droplets that pass through them.  They found that water vapor collection could be made much more efficient by zapping the tiny droplets of water with an ion beam, giving them a slight electric charge, thereby making it easy to capture them with the metal mesh of the harvesting system.

The system can essentially eliminate cooling tower plumes and produce large quantities of high-purity water in the process, which has uses at many power plants.  The new company, called Infinite Cooling, has arranged to install their equipment on two operating commercial power plants later this year.  They expect the system to reduce the overall need for water by 20%.

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Vapor-collection technology saves water while clearing the air

Photo, posted March 5, 2019, courtesy of Sam LaRussa via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Better Batteries For The Grid | Earth Wise

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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.

Improving Solar Cells With Human Hair | Earth Wise

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Researchers at the Queensland University of Technology in Australia have been able to improve the performance of perovskite solar cells using material made from human hair.

Perovskite solar cells are an up-and-coming technology that offers the possibility of making solar cells less expensive, more efficient, and flexible so that there could be solar-powered clothing, backpacks, or even tents for camping.  While the technology has been shown to be as effective in converting sunlight to electricity as currently available silicon technology, it faces problems with stability and durability.

The Australian research centered on the use of carbon nanodots to improve perovskite solar cell performance.  The nanodots were created in a rather unique way.  The carbon came from hair scraps from a Brisbane barbershop that were first broken down and then burned at nearly 500 degrees Fahrenheit. 

By adding a solution of the carbon nanodots into the process of making the perovskites, the dots formed a wave-like layer in which the perovskite crystals in the cells are surrounded by the carbon dots.  It serves as a protective layer, essentially a kind of armor, for the active portions of the material.

The result was solar cells with a higher power conversion efficiency and greater stability.  The researchers did not explain why they chose human hair as the source of carbon, but it does make for an interesting sidelight to the promising research.

Perovskite solar cells could be very important for spacecraft applications where reducing weight is paramount.  But in order to be able to use them for this purpose, perovskite solar cells will need to be able to cope with the extreme radiation and temperature variations in space.

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Carbon dots from human hair boost solar cells

Photo, posted October 3, 2009, courtesy of Arktoi via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Red Hot Chili Solar Panels | Earth Wise

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The majority of solar panels in use today are made from either single-crystal or polycrystalline silicon, the same stuff used to make the ubiquitous chips in computers, cell phones, and countless other devices.  In addition, a growing fraction of solar panels utilize thin-film technology, which offers cost and flexibility advantages.

Monocrystal silicon still provides the highest efficiency and longest lifespan in commercially available panels, but the lower costs and some other features of thin-film solar panels are growing that market over time.

More recently, perovskite solar cell technology has been a source of great interest in the research community.  Perovskites are a class of minerals with a specific crystalline structure that already have uses in various applications.  As a solar cell material, perovskites offer the potential for converting more sunlight to electricity, being manufactured far more cheaply using no exotic or expensive materials, being more defect-tolerant, as well as a having number of other advantages.  They also have the potential for having very high efficiency. 

Recently, a group of researchers in China and Sweden published results of studies demonstrating that the addition of a novel ingredient has increased the efficiency of perovskite solar cells to nearly 22%, which is better than most commercial silicon solar cells.  The ingredient is capsaicin, the chemical that gives chili peppers their spicy sting.  Adding capsaicin expands the grains that make up the active material of the solar cell, allowing the more effective transport of electricity. 

Why did the researchers think of adding the active ingredient of hot peppers to a solar cell in the first place?  So far, they aren’t saying.

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Solar panels capture more sunlight with capsaicin – the chemical that makes chili peppers spicy

Photo, posted August 16, 2019, courtesy of Pedro via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Path To Net Zero | Earth Wise

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Reaching net zero emissions is both feasible and affordable, according to researchers at the Department of Energy’s Lawrence Berkeley National Laboratory, the University of San Francisco, and consulting firm Evolved Energy Research.   The researchers created a detailed model of the entire U.S. energy and industrial system to produce the first detailed, peer-reviewed study of how to achieve carbon neutrality by 2050.

The study analyzed multiple feasible technology pathways based on very different assumptions of remaining fossil fuel use, land use, consumer adoption, nuclear energy, and biofuel use.  What they had in common was increasing energy efficiency, transitioning to electric technologies, utilizing clean electricity (especially wind and solar power), and deploying small amounts of carbon capture technology.

The decarbonization of the U.S. energy system is an infrastructure transformation.  Getting to net zero by 2050 means adding many gigawatts of wind and solar power plants, new transmission lines, a fleet of electric cars and light trucks, millions of heat pumps to replace conventional furnaces and water heaters, and more energy-efficient buildings.

The various pathways studied have net costs between 0.2% and 1.2% of GDP, which is as little as $1 per person per day.  The cost variations come from various tradeoffs such as the amount of land given to solar and wind farms as well as the amount of new transmission infrastructure required. 

A key result of the study is that the actions required over the next 10 years are similar among all the pathways.   We need to increase the use of renewable energy and make sure that all new infrastructure, such as cars and buildings are low carbon.

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Getting to Net Zero – and Even Net Negative – is Surprisingly Feasible, and Affordable

Photo, posted July 12, 2010, courtesy of Tom Shockey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Hydrogen-Powered Transport In Britain | Earth Wise

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The first hydrogen-powered train in the UK had its first mainline runs at the end of September.  The train, known as HydroFLEX, was developed under a project headed by the University of Birmingham under the UK government’s Department for Transport. 

Hydrogen-powered trains do not emit harmful gases but rather use hydrogen and oxygen to produce electricity, water, and heat.  The technology in the HydroFLEX train will be available by 2023 to retrofit existing diesel-powered trains and thereby de-carbonize the rail network and make train travel greener and more efficient.

The UK has ambitious plans for the use of hydrogen technology.  The Department of Transport plans to publish a master plan in January that will outline how green hydrogen could power buses, trucks, rail, maritime, and aviation transport across the UK.

The HydroFLEX trial is taking place in Tees Valley in northeastern England and the plan is for that area to become a Hydrogen Transport Hub that will include the world’s largest versatile hydrogen refueling facility.   The plans for Tees Valley involve academia, industry, and government participants.  The next stages of the HydroFLEX project are well underway with the University of Birmingham developing a hydrogen and battery-powered module that can be fitted underneath a train to allow for more space for passengers in train cars.

The UK government’s Hydrogen for Transport Program is also funding a green hydrogen refueling station and 19 hydrogen-powered garbage trucks in Glasgow, Scotland.

The UK plans to switch to a net zero economy and their current program increasingly embraces hydrogen technology to provide more sustainable, greener forms of transportation.

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UK embraces hydrogen-fueled future as transport hub and train announced

Photo, posted May 15, 2019, courtesy of Jeremy Segrott via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Recycling Solar Panels | Earth Wise

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It is inevitable that the things we make and use eventually outlive their useful lives and become waste that we have to deal with.  Solar panels, despite their impressively long lifetime, can’t escape this general principle.   As pioneering solar panels near the end of their 30-year electronic lives, they could well become the world’s next big wave of e-waste.

According to the International Renewable Energy Agency, nearly 90 million tons of solar panels will have reached their end of life by the year 2050, resulting in about 7 million tons of new solar e-waste per year.

Solar photovoltaic deployment has grown at unprecedented rates in recent years.  The total global installed capacity is about 600 GW today; projections are that there will be 1,600 GW by 2030 and 4,500 GW by 2050.

Solar panels contain valuable materials, including silver and high-purity silicon.  But current recycling procedures are not cost-effective.   Only about 10% of panels are currently recycled in the U.S.   The rest go to landfills or are shipped overseas to become another country’s problem.

Before solar waste becomes a major problem, the industry needs to better address the issue.  Strategies include improving the design of panels to align with recycling capabilities as well as developing new recycling methods that can more efficiently extract and purify the valuable materials in the panels.  Industry researchers are also looking into ways to repair and resell panels that are still in good condition and to repurpose old panels for less demanding functions like e-bike charging stations and housing complexes.

Like most things, solar panels do fail over time and with a rapidly growing number of them in the world, we need to figure out how to avoid them adding to the world’s problems.

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Solar Panels Are Starting to Die. Will We be Able to Recycle the E-Waste?

Photo, posted January 6, 2006, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)