efficiency

Recycling Solar Panels | Earth Wise

October 1, 2020 By EarthWise Leave a Comment

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.

Generating Hydrogen From Poor-Quality Water | Earth Wise

September 8, 2020 By EarthWise Leave a Comment

Hydrogen could be the basis of a complete energy system. It could be stored and transported and could be used to power vehicles and to generate electricity in power plants. Proponents of the so-called hydrogen economy contend that hydrogen is the best solution to the global energy challenge. But among the challenges faced by a hydrogen economy is the development of an efficient and green method to produce hydrogen.

The primary carbon-free method of producing hydrogen is to break down water into its constituent elements – hydrogen and oxygen. This can be done in a number of ways, notably by using electricity in a process called electrolysis. A method that seems particularly attractive is to use sunlight as the energy source that breaks down the water molecule.

While there is an abundance of water on our planet, only some of it is suitable for people to drink and consume in other ways. Much of the accessible water on earth is salty or polluted. So, a technique to obtain hydrogen from water ideally should work with water that is otherwise of little use to people.

Researchers in Russia and the Czech Republic have recently developed a new material that efficiently generates hydrogen molecules by exposing water – even saltwater or polluted water – to sunlight.

The new material is a three-layer structure composed of a thin film of gold, an ultra-thin layer of platinum, and a metal-organic framework or MOF of chromium compounds and organic molecules. The MOF layer acts as a filter that gets rid of impurities.

Experiments have demonstrated that 100 square centimeters of the material can generate half a liter of hydrogen in an hour. The researchers continue to improve the material and increase its efficiency over a broad range of the solar spectrum.

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New Material Can Generate Hydrogen from Salt and Polluted Water

Photo courtesy of Tomsk Polytechnic University.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Membrane For Converting Carbon Dioxide | Earth Wise

March 24, 2020 By EarthWise Leave a Comment

Methanol is a valuable chemical used as fuel in the production of countless products. Carbon dioxide is a greenhouse gas that is produced by countless industrial processes. Carbon dioxide can be converted into methanol, which is one way all that CO2 can be put to good use instead of causing harm.

In research recently published in Science, chemical engineers from Rensselaer Polytechnic Institute have developed a process that converts CO2 to methanol in a more efficient way by using a highly effective separation membrane they produced.

The chemical reaction responsible for the transformation of CO2 into methanol also produces water, which severely restricts the continued reaction. The Rensselaer team has found a way to filter out the water as the reaction is happening, without losing other essential gas molecules.

They produced a membrane made up of sodium ions and zeolite crystals that was able to carefully and quickly permeate water through small pores — known as water-conduction nanochannels — without losing gas molecules. The sodium ions effectively only allow water to go through. When water was effectively removed from the process, the team found that the chemical reaction was able to happen very quickly. By removing the water, the equilibrium shifts, which means more CO2 will be converted and more methanol will be produced.

The team is now working to develop a scalable process and a startup company that would allow this membrane to be used commercially to produce high purity methanol. This membrane could also be used to improve a number of other reactions.

In industry there are many reactions limited by water and this RPI membrane could be an important enhancement for many of them.

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Water-Conducting Membrane Allows Carbon Dioxide To Transform into Fuel More Efficiently

Photo courtesy of RPI.

Earth Wise is a production of WAMC Northeast Public Radio.

Figuring Out Photosynthesis | Earth Wise

March 16, 2020 By EarthWise Leave a Comment

Plants have been harnessing the sun’s energy for hundreds of millions of years. Algae and photosynthetic bacteria have been doing the same for even longer, all with remarkable efficiency and resiliency.

People have used the energy of the sun in one way or another for millennia, but only recently have we gotten sophisticated about it by using devices like solar panels and sensors. And we still have a long way to go to get anywhere close to the efficiency of plants. It’s no wonder, then, that scientists have long sought to understand exactly how photosynthesis works.

Scientists from the U.S. Department of Energy’s (DOE) Argonne National Laboratory, and collaborators at Washington University in St. Louis, recently solved a critical part of the age-old mystery of photosynthesis, studying the initial, ultra-fast events through which photosynthetic proteins capture light and use it to initiate a series of electron transfer reactions. Electrons in plants have two possible pathways to travel but only use one.

But as a result of their efforts, the scientists are now closer than ever to being able to design electron transfer systems in which they can send an electron down a pathway of their choosing.

By gaining the ability to harness the flow of energy, it may be possible to incorporate new design principles in non-biological energy systems. This could allow us to greatly improve the efficiency of many solar-powered devices, potentially making them far smaller. Understanding the intricacies of photosynthesis creates a tremendous opportunity to open up completely new disciplines of light-driven biochemical reactions, perhaps even ones that haven’t been envisioned by nature.

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Scientists unravel mystery of photosynthesis

Photo, posted June 14, 2017, courtesy of Alex Holyoake via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Saving Costs And Reducing Emissions From Shipping | Earth Wise

March 2, 2020 By EarthWise Leave a Comment

International shipping is a large and growing source of greenhouse gas emissions. Maritime transport produces about a billion tons of CO2 annually, accounting for about 2.5% of global greenhouse gas emissions. The environmental impact of shipping includes air pollution, water pollution, and even acoustic pollution. In many coastal areas, ships are responsible for more than 18% of some air pollutants. Overall, there are more than 100,000 transport ships at sea, of which about 6,000 are large container ships.

In recent years, the shipping sector has had both internal willingness and external pressure to reduce emissions, but shipping is a tough, competitive business and it isn’t easy to stay competitive and help protect the environment.

A recent study at Abo Akademi University in Finland has found that improved ship utilization rates and investments in environmentally sustainable technologies for enhanced energy efficiency would significantly reduce carbon dioxide emissions. Of equal importance, those same measures would contribute to lowering of freight costs.

If the same cargo volume can be shipped using less fuel, shipping companies will gain major savings in terms of fuel costs. Digitalization can provide valuable benefits. For example, new digital planning and booking systems would enable smarter use of routes while also diminishing traffic with half-empty vessels or even ones with no cargo aboard. Reducing such underutilization would improve the capacity utilization rate and eliminate emissions caused by so-called ballast traffic.

Global shipping continues to grow. It is essential that it becomes smarter and more efficient to protect the environment and improve its economics.

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Environmentally friendly shipping helps to reduce freight costs

Photo, posted February 18, 2016, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The New York Climate Plan

July 24, 2019 By EarthWise Leave a Comment

New York lawmakers have passed a sweeping climate plan that requires the state to eliminate almost all of its greenhouse gas emissions by 2050. The plan calls for the phase-out of gasoline cars and oil- and gas-burning furnaces and requires all of the state’s electricity to come from carbon-free sources.

The Climate Leadership and Community Protection Act requires the state to slash its carbon emissions to 85% below 1990 levels by 2050 and to offset the remaining 15% by other means such as removing carbon dioxide from the atmosphere. The bill requires New York to get 70% of its electricity from renewable sources by 2030.

The challenges of reaching the program’s goals are daunting. New York has so far only reduced its emissions by 8% since 1990. The state currently does get 60% of its electricity from carbon-free sources – mostly hydroelectric dams and nuclear power plants – but it will require offshore windfarms, ramped-up solar installations, and battery storage systems to push the numbers dramatically higher.

Transportation, which is responsible for a third of New York’s emissions, will be particularly tough to tackle. The Trump administration is rolling back federal vehicle efficiency rules and is trying to prevent states from setting stricter standards. Currently, electric car ownership is primarily attractive for single-family homeowners who can plug in their cars at home. Far more pervasive charging stations – for example, all over the streets of New York City – would be needed to make electric cars practical for everyone.

The plan aims for industries to bear most of the financial burden, but supporters say that the costs of not acting on climate will be vastly greater for businesses. The plan’s deadlines for major emissions reductions are a decade away but there will be much to do quite soon.

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New York to Approve One of the World’s Most Ambitious Climate Plans

Photo, posted September 17, 2009, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Another Way To Make Solar Cells

March 21, 2019 By EarthWise Leave a Comment

Millions of rooftops now contain solar panels and the majority of the solar cells that make up those panels today are made from silicon. Silicon solar cells require expensive, multi-step processing conducted at very high temperatures in special clean room facilities. Despite these complications, the price of solar panels has continued to drop dramatically over the years.

But even as the price of solar cells gets lower and lower, there are still widespread efforts to find even better ways to make them. One of those ways is with perovskite solar cells. Perovskites are materials with a characteristic crystal structure and are quite common in nature. Perovskites can be formed with a wide range of elements and can exhibit a variety of properties.

They were first used to make solar cells about 10 years ago and those first cells were unimpressive in most respects. However, there has been steady progress since that time. The potential advantages of perovskite solar cells are that they can be made from low-cost materials and can be manufactured using liquid chemistry, a far cheaper process than what is used to make silicon cells.

Researchers at MIT and several other institutions have recently published the results of research on how to tailor the composition of perovskite solar cells to optimize their properties. What used to be a trial-and-error process can now become much more engineered and should lead to perovskite solar cells with performance that could exceed that of silicon cells.

Silicon solar panels are a huge, worldwide industry and displacing them in favor of an alternative technology is a tall order. But if perovskite cells can be optimized for large-scale manufacturability, efficiency and durability, they could definitely give silicon a run for its money.

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Unleashing perovskites’ potential for solar cells

Photo courtesy of Ken Richardson/MIT.

Earth Wise is a production of WAMC Northeast Public Radio.

A New Way to Make Hydrogen

January 31, 2019 By EarthWise Leave a Comment

Many people consider hydrogen to be the fuel of the future, both for powering vehicles and for storing energy generated by renewable sources. Hydrogen itself is a clean and green fuel. Generating energy from it using fuel cells results in only water as a byproduct.

The biggest problem with hydrogen is that the most economical way to produce it and therefore the way most hydrogen is produced today, is by reforming natural gas, which is a process that generates carbon emissions.

The desirable way to make hydrogen is to produce it by breaking apart water into its hydrogen and oxygen components, a process known as electrolysis. There are many ways to do it, but none of them to date measures up in terms of efficiency, cost, and longevity.

Researchers at the University of Toronto have recently developed a new catalyst that uses abundant, low-cost elements to split water molecules into hydrogen and oxygen. The catalyst is made from copper, nickel, and chromium, all of which are more abundant and less costly than platinum, which is the usual electrolysis catalyst.

The new catalyst performs well under pH-neutral conditions, which means it could even work on seawater without incurring the expense of desalination. The Toronto researchers also believe their catalyst could be used as part of a process to make hydrocarbon fuels from hydrogen and CO2₂. Their group is among the five finalists in the Carbon XPrize competition, which has a grand prize of $7.5 million for finding a way to convert waste CO2 into fuel.

Finding a low-cost, energy-efficient, and reliable way to make hydrogen out of water will be a big deal if it can be done on an industrial scale.

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U of T researchers discover low-cost way to produce hydrogen from water

Photo, posted July 23, 2015, courtesy of Magnus Johansson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Breakthrough In Animal Identification

December 25, 2018 By EarthWise Leave a Comment

Researchers from the University of Wyoming have developed a computer model that can identify wild animals in camera-trap photographs with remarkable accuracy and efficiency.

This breakthrough in artificial intelligence (AI), detailed in a paper recently published in the scientific journal Methods in Ecology and Evolution, represents a significant advancement in the study and conservation of wildlife. According to the paper’s authors, “the ability to rapidly identify millions of images from camera traps can fundamentally change the way ecologists design and implement wildlife studies.”

This study builds on previous research from the university in which a computer model analyzed 3.2 million images captured by camera traps in Africa. The A-I technique called deep learning categorized animal images at a 96.6% accuracy rate. This was the same accuracy rate as teams of human volunteers achieved, but the computer model worked at a much more rapid pace.

In the latest study, UW researchers trained a deep neural network on a powerful computer cluster to classify wildlife species using 3.37 million camera-trap images of 27 different animal species. The model was tested on nearly 375,000 images at a rate of about 2,000 images per minute. It achieved a 97.6% accuracy rate, which is likely the highest accuracy to date in using machine learning for wildlife image classification.

Artificial intelligence has been used in environmental science in other ways as well. For example, AI has been used to increase agricultural yields in farm fields and to help predict extreme weather.

Maybe artificial intelligence can prove to be a game changer for the environment.

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Researchers Successfully Train Computers to Identify Animals in Photos

Photo, posted January 8, 2012, courtesy of the U.S. Fish and Wildlife Service via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Accelerating Sugarcane Growth

September 21, 2018 By EarthWise Leave a Comment

Brazil is the world’s second largest producer of ethanol fuel behind the United States. More than that, it has the first sustainable biofuel economy, which is based on sugarcane ethanol, not corn ethanol. It is sustainable because of Brazil’s advanced agri-industrial technology and its enormous amount of arable land. Furthermore, producing sugarcane ethanol is far more energy-efficient than corn ethanol. It actually makes energy sense to produce it.

Bacteria-Powered Solar Cell

August 29, 2018 By EarthWise 1 Comment

Commercially-available solar panels are composed of solar cells that are most often made from various forms of silicon. Some panels use thin-film cells made from other semiconductor materials. Solar cells utilize a property of semiconductors that allows them to convert light energy into electrical energy.

Feeding Seaweed To Cows

August 16, 2018 By EarthWise Leave a Comment

Methane emissions are a real problem. As a greenhouse gas, methane has at least 25 times the heat-trapping power of carbon dioxide. More than a third of all the methane that humans are responsible for putting into the atmosphere comes from domestic livestock: cattle, sheep, goats and buffalo. In California alone, dairy cows along with a smaller number of beef cattle emit the heat trapping equivalent of the emissions from 2.5 million cars.

Using Less Water

July 26, 2018 By EarthWise Leave a Comment

In recent times, there has been a downward trend in water use in the United States. It has been driven by increasingly efficient use of critical water resources in the face of persistent droughts in various parts of the country and awareness of the importance of conserving this resource.

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Fresh Water From Power Plants

July 24, 2018 By EarthWise Leave a Comment

A new system developed by MIT engineers could provide a low-cost source of drinking water and simultaneously reduce power plant operating costs.

The Fight For Greener Cars

June 28, 2018 By EarthWise Leave a Comment

U.S. automakers have always been reluctant partners in the nation’s efforts to reduce air pollution and improve fuel efficiency. There have been struggles for decades between the carmakers and the government in setting Corporate Average Fuel Economy (or CAFÉ) standards. During the Obama administration, some of the most demanding fuel economy and emissions standards were mandated.

New Energy Goals For New York

June 1, 2018 By EarthWise Leave a Comment

Since 2015, New York has had in place an energy plan aimed at building a clean, resilient and cost-effective energy system for the state. A key part of that plan is to reduce greenhouse gas emissions by 40% from 1990 levels by the year 2030. Another major goal is to have 50% of the state’s electricity produced from renewable sources by the same year.

Water From Desert Air

May 7, 2018 By EarthWise Leave a Comment

Last spring, we talked about a solar-powered water harvester designed to pull water out of even dry desert air. The prototype device was described in a paper by scientists at UC Berkeley and MIT in the journal Science.

Green Tech In 2018

January 25, 2018 By EarthWise Leave a Comment

Clean power gathered unprecedented momentum in 2017. With climate problems on the rise, national and local governments are pushing for more renewable energy and the end of fossil-fueled cars. Corporations around the globe are making major commitments to green technology. Despite the Trump Administration’s open hostility toward clean power and its rejection of climate science, American states, municipalities and private companies are all getting with the program.

[Read more…] about Green Tech In 2018

Transparent Solar Panels

December 6, 2017 By EarthWise Leave a Comment

It is now commonplace to see solar panels on the rooftops of homes and businesses. There are more than a million solar homes in the US alone. But a new generation of see-through solar technology has the potential to also turn the windows of buildings and cars, as well as other glass-coated objects, into electricity generators.

The Perils Of Air Conditioning

September 12, 2017 By EarthWise

The battle to reduce greenhouse gas emissions is heavily focused on replacing fossil fuel power plants with renewable energy and replacing internal combustion engine autos with electric cars. But there is another elephant in the room: air conditioners.