Posts belonging to Category green power



How To Clean Nuclear Waste

Cleaning up radioactive waste is a dangerous job for a human. That’s why researchers at the University of  Manchester are developing robots that could do the job for us. Five years ago, in 2011, a major earthquake and tsunami devastated the east coast of Japan, leading to explosions and subsequent radiation release at the Fukushima Daiichi Nuclear Power Station. The fuel in three of the reactors is believed to have melted, causing a large amount of contaminated water on site.

This is still to be dealt with today – which isn’t too surprising, given that the clean-up of Chernobyl is still underway 30 years after the infamous nuclear accident took place. After the accident at Chernobyl, where an extremely high level of radiation was released, workers had to be sent into areas to which you wouldn’t want to send a human being. For the safety of others, they entered the plant to survey its condition, extinguish fires and manually operate equipment and machinery – all in an environment that endangered their lives. The challenge in dismantling the site at Fukushima is the residual radiation level. In the surrounding areas levels have fallen significantly; in some places (still off limits to former residents) radiation levels actually aren’t very different from natural background levels in certain other parts of the world. But in the reactor itself a person would receive a lethal dose of radiation almost instantly.

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At Fukushima, many of the instrumentation systems, such as reactor-water level and reactor pressure, were lost in the incident. This made assessing the integrity of the plant extremely difficult as you couldn’t send people to go and look at it,” explains Professor Barry Lennox, who, alongside Dr Simon Watson at The University of Manchester, is working to find another way of getting access to such dangerous places: by using robots. Professor Lennox and Dr Watson are part of a team working to adapt robots to help clean up Fukushima. They’re developing an underwater remote-operated vehicle – the AVEXIS – to help identify highly radioactive nuclear fuel that is believed to be dispersed underwater in the damaged reactor. The robot is already aiding decommissioning efforts at Sellafield, where it will swim around the ponds storing legacy waste to map and monitor the conditions within them.

Source: https://www.manchester.ac.uk/

How To Charge Lithium Batteries 20 Times Faster

A touch of asphalt may be the secret to high-capacity lithium metal batteries that charge 10 to 20 times faster than commercial lithium-ion batteries, according to Rice University scientists. The Rice lab of chemist James Tour developed anodes comprising porous carbon made from asphalt that showed exceptional stability after more than 500 charge-discharge cycles. A high-current density of 20 milliamps per square centimeter demonstrated the material’s promise for use in rapid charge and discharge devices that require high-power density.

Scanning electron microscope images show an anode of asphalt, graphene nanoribbons and lithium at left and the same material without lithium at right. The material was developed at Rice University and shows promise for high-capacity lithium batteries that charge 20 times faster than commercial lithium-ion batteries

The capacity of these batteries is enormous, but what is equally remarkable is that we can bring them from zero charge to full charge in five minutes, rather than the typical two hours or more needed with other batteries,” Tour said.

The Tour lab previously used a derivative of asphalt — specifically, untreated gilsonite, the same type used for the battery — to capture greenhouse gases from natural gas. This time, the researchers mixed asphalt with conductive graphene nanoribbons and coated the composite with lithium metal through electrochemical deposition. The lab combined the anode with a sulfurized-carbon cathode to make full batteries for testing. The batteries showed a high-power density of 1,322 watts per kilogram and high-energy density of 943 watt-hours per kilogram.

Testing revealed another significant benefit: The carbon mitigated the formation of lithium dendrites. These mossy deposits invade a battery’s electrolyte. If they extend far enough, they short-circuit the anode and cathode and can cause the battery to fail, catch fire or explode. But the asphalt-derived carbon prevents any dendrite formation.

The finding is reported in the American Chemical Society journal ACS Nano.

Source: http://news.rice.edu/

How To Extract Hydrogen Fuel from Seawater

It’s possible to produce hydrogen to power fuel cells by extracting the gas from seawater, but the electricity required to do it makes the process costly. UCF researcher Yang Yang from the University of Central Florida (UCF)  has come up with a new hybrid nanomaterial that harnesses solar energy and uses it to generate hydrogen from seawater more cheaply and efficiently than current materials. The breakthrough could someday lead to a new source of the clean-burning fuel, ease demand for fossil fuels and boost the economy of Florida, where sunshine and seawater are abundant. Yang, an assistant professor with joint appointments in the University of Central Florida’s NanoScience Technology Center and the Department of Materials Science and Engineering, has been working on solar hydrogen splitting for nearly 10 years.

It’s done using a photocatalyst – a material that spurs a chemical reaction using energy from light. When he began his research, Yang focused on using solar energy to extract hydrogen from purified water. It’s a much more difficulty task with seawater; the photocatalysts needed aren’t durable enough to handle its biomass and corrosive salt.

We’ve opened a new window to splitting real water, not just purified water in a lab,” Yang said. “This really works well in seawater.”

As reported in the journal Energy & Environmental Science, Yang and his research team have developed a new catalyst that’s able to not only harvest a much broader spectrum of light than other materials, but also stand up to the harsh conditions found in seawater.

 

Source: https://today.ucf.edu/

Paper Supercapacitor

By coating ordinary paper with layers of gold nanoparticles and other materials, researchers have fabricated flexible paper supercapacitors that exhibit the best performance of any textile-type supercapacitor to date. In particular, the paper supercapacitors address one of the biggest challenges in this area, which is to achieve a high energy density in addition to an already high power density, since both properties are essential for realizing high-performance energy-storage devices. In the future, flexible paper supercapacitors could be used in wearable electronics for biomedical, consumer, and military applications. The researchers, led by Seung Woo Lee at the Georgia Institute of Technology and Jinhan Cho at Korea University, have published a paper on the flexible paper supercapacitor electrodes in a recent issue of Nature Communications. As energy-storage devices, supercapacitors have several advantages over batteries, such as a higher power density, rapid charge/discharge rate, and longer lifetime, yet they lag behind batteries in energy density (the amount of energy that can be stored in a given amount of space). Although several methods have been attempted to improve the energy density of paper supercapacitors by coating them with various conductive materials, often these methods have the drawback of reducing the power density.

The paper electrodes based on layer-by-layer-assembled metal nanoparticles exhibit metal-like electric conductivity, paper-like mechanical properties, and a large surface area without any thermal treatment and/or mechanical pressing,” explains coauthor Yongmin Ko at Korea University. “The periodic insertion of metal nanoparticles within high-energy nanoparticle-based paper electrodes could resolve the critical tradeoff in which an increase in the loading amount of materials to enhance the energy density of supercapacitors decreases the power density.”
Tests  showed that the flexible paper supercapacitors had a maximum capacitance that is higher than any previously reported textile-based supercapacitor. In addition, the new devices exhibits an excellent capacity retention, demonstrated by a 90% capacity retention after 5,000 bending cycles.

Source: http://me.gatech.edu/

Flying Electric Planes Between London And Paris

EasyJet could be flying planes powered by batteries rather than petroleum to destinations including Paris and Amsterdam within a decade. The UK carrier has formed a partnership with US firm Wright Electric, which is developing a battery-propelled aircraft for flights under two hoursEasyJet said the move would enable battery-powered aircraft to travel short-haul routes such as London to Paris and Amsterdam, and Edinburgh to Bristol. Wright Electric is aiming for an aircraft range of 335 miles, which would cover the journeys of about a fifth of passengers flown by easyJet.

Carolyn McCall, easyJet’s chief executive, said the aerospace industry would follow the lead of the automotive industry in developing electric engines that would cut emissions and noise.

For the first time in my career I can envisage a future without jet fuel and we are excited to be part of it,” she said. “It is now more a matter of when, not if, a short-haul electric plane will fly.”

The company said it was the next step in making the airline less harmful for the environment, after cutting carbon emissions per passenger kilometre by 31% between 2000 and 2016. Wright Electric claims that electric planes will be 50% quieter and 10% cheaper for airlines to buy and operate, with the cost saving potentially passed on to passengers. The US firm said its goal was for every short flight to be electric within 20 years. It has already built a two-seater prototype and is working towards a fully electric plane within a decade. The next step is to scale-up the technology to a 10-seater aircraft, and eventually to build a single aisle, short haul commercial plane, with the capacity to carry at least 120 passengers.

Source: https://www.theguardian.com/

Renewable Fuel From Water

Physicists at Lancaster University (in UK) are developing methods of creating renewable fuel from water using quantum technologyRenewable hydrogen can already be produced by photoelectrolysis where solar power is used to split water molecules into oxygen and hydrogen. But, despite significant research effort over the past four decades, fundamental problems remain before this can be adopted commercially due to inefficiency and lack of cost-effectivenessDr Manus Hayne  from the Department of Physics said: “For research to progress, innovation in both materials development and device design is clearly needed.

The Lancaster study, which formed part of the PhD research of Dr Sam Harrison, and is published in Scientific Reports, provides the basis for further experimental work into the solar production of hydrogen as a renewable fuel. It demonstrates that the novel use of nanostructures could increase the maximum photovoltage generated in a photoelectrochemical cell, increasing the productivity of splitting water molecules.

To the authors’ best knowledge, this system has never been investigated either theoretically or experimentally, and there is huge scope for further work to expand upon the results presented here,” said Dr Haynes. “Fossil-fuel combustion releases carbon dioxide into the atmosphere, causing global climate change, and there is only a finite amount of them available for extraction. We clearly need to transition to a renewable and low-greenhouse-gas energy infrastructure, and renewable hydrogen is expected to play an important role.

Fossil fuels accounted for almost 90% of energy consumption in 2015, with absolute demand still increasing due to a growing global population and increasing industrialisationPhotovoltaic solar cells are currently used to convert sunlight directly into electricity but solar hydrogen has the advantage that it is easily stored, so it can be used as and when needed. Hydrogen is also very flexible, making it highly advantageous  for remote communities. It can be converted to electricity in a fuel cell, or burnt in a boiler or cooker just like natural gas. It can even be used to fuel aircraft.

Source: http://www.lancaster.ac.uk/

Biomaterial To Replace Plastics And Reduce Pollution

An inexpensive biomaterial that can be used to sustainably replace plastic barrier coatings in packaging and many other applications has been developed by Penn State researchers, who predict its adoption would greatly reduce pollution. Completely compostable, the material — a polysaccharide polyelectrolyte complex — is comprised of nearly equal parts of treated cellulose pulp from wood or cotton, and chitosan, which is derived from chitin — the primary ingredient in the exoskeletons of arthropods and crustaceans. The main source of chitin is the mountains of leftover shells from lobsters, crabs and shrimp consumed by humans.

These environmentally friendly barrier coatings have numerous applications ranging from water-resistant paper, to coatings for ceiling tiles and wallboard, to food coatings to seal in freshness, according to lead researcher Jeffrey Catchmark, professor of agricultural and biological engineering, College of Agricultural Sciences.

In the research, paperboard coated with the biomaterial exhibited strong oil and water barrier properties. The coating also resisted toluene, heptane and salt solutions and exhibited improved wet and dry mechanical and water vapor barrier properties.

The material’s unexpected strong, insoluble adhesive properties are useful for packaging as well as other applications, such as better performing, fully natural wood-fiber composites for construction and even flooring,” Jeffrey Catchmark said. “And the technology has the potential to be incorporated into foods to reduce fat uptake during frying and maintain crispness. Since the coating is essentially fiber-based, it is a means of adding fiber to diets.”

Source: http://news.psu.edu/

Urban Farming At Home

Growing your own vegetables and herbs can be a laborious process. Lack of space in urban environments makes it even harder. But this smart garden is bringing the window box into the modern age. Much like Nespresso coffee capsules, users ‘plant’ this soil pod… containing the seeds and all the nutrients which are released in sync with the plant’s life cycle.

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This is the plastic container they put the growing substrate in here. It has a wick solution, so basically it starts to drain the water from the water tank, and the lamp does the rest of the job. The lamp imitates daylight time, so it’s 16 hours on and 8 hours off. So far we have tested some 7,000 different plants and each growing substrate is designed specifically for this plant,” says Karel Kask, sales Manager, Click and Grow. Estonia-based ‘Click and Grow‘ says it’s tested up to a thousand lighting solutions to ensure optimal growth. The red and white lights deliver the perfect spectrum they say, speeding up growth by 30 to 50 percent, depending on the plant. Each soil pod provides up to 3 harvests. ‘Click and Grow‘ was inspired by NASA technology used to grow food in space. Here, astronauts aboard the International Space Station sample lettuce they’ve grown.

They’re using quite similar soil-based solutions; so they take the soil substrate into space and grow them already in there. They have an automated watering solution. So it’s quite similar to the solution that we do.The Smart Garden 9, its latest and most advanced model, was displayed at this week’s IFA tech fair in Berlin,” adds Kask.

More Durable Fuel Cells For Hydrogen Electric Car

Take a ride on the University of Delaware’s (UDFuel Cell bus, and you see that fuel cells can power vehicles in an eco-friendly way. In just the last two years, Toyota, BMW and Honda have released vehicles that run on fuel cells, and carmakers such as GM, BMW and VW are working on prototypes.  If their power sources lasted longer and cost less, fuel cell vehicles could go mainstream faster. Now, a team of engineers at UD has developed a technology that could make fuel cells cheaper and more durable.

Hydrogen-powered fuel cells are a green alternative to internal combustion engines because they produce power through electrochemical reactions, leaving no pollution behind. Materials called catalysts spur these electrochemical reactions. Platinum is the most common catalyst in the type of fuel cells used in vehicles. However, platinum is expensive — as anyone who’s shopped for jewelry knows. The metal costs around $30,000 per kilogram. Instead, the UD team made a catalyst of tungsten carbide, which goes for around $150 per kilogram. They produced tungsten carbide nanoparticles in a novel way, much smaller and more scalable than previous methods.

The material is typically made at very high temperatures, about 1,500 Celsius, and at these temperatures, it grows big and has little surface area for chemistry to take place on,” explains Vlachos, professor at the Catalysis Center for Energy Innovation (UD). “Our approach is one of the first to make nanoscale material of high surface area that can be commercially relevant for catalysis.”

The researchers made tungsten carbide nanoparticles using a series of steps including hydrothermal treatment, separation, reduction, carburization and more. The results are described in a paper published in Nature Communications.

Source: https://www.udel.edu/

China, Global Leader In NanoScience

Mobile phones, computers, cosmetics, bicyclesnanoscience is hiding in so many everyday items, wielding a huge influence on our lives at a microscale level. Scientists and engineers from around the world exchanged new findings and perceptions on nanotechnology at the recent 7th International Conference on Nanoscience and Technology (ChinaNANO 2017) in Beijing last week. China has become a nanotechnology powerhouse, according to a report released at the conference. China’s applied nanoscience research and the industrialization of nanotechnology have been developing steadily, with the number of nano-related patent applications ranking among the top in the world.

According to Bai Chunli, president of the Chinese Academy of Sciences (CAS), China faces new opportunities for nanoscience research and development as it builds the National Center for Nanoscience and Technology  (NCNST) and globally influential national science centers.

We will strengthen the strategic landscape and top-down design for developing nanoscience, which will contribute greatly to the country’s economy and society,” said Bai.

Nanoscience can be defined as the study of the interaction, composition, properties and manufacturing methods of materials at a nanometer scale. At such tiny scales, the physical, chemical and biological properties of materials are different from those at larger scales — often profoundly so.

For example, alloys that are weak or brittle become strong and ductile; compounds that are chemically inert become powerful catalysts. It is estimated that there are more than 1,600 nanotechnology-based consumer products on the market, including lightweight but sturdy tennis rackets, bicycles, suitcases, automobile parts and rechargeable batteries. Nanomaterials are used in hairdryers or straighteners to make them lighter and more durable. The secret of how sunscreens protect skin from sunburn lies in the nanometer-scale titanium dioxide or zinc oxide they contain.

In 2016, the world’s first one-nanometer transistor was created. It was made from carbon nanotubes and molybdenum disulphide, rather than silicon.
Carbon nanotubes or silver nanowires enable touch screens on computers and televisions to be flexible, said Zhu Xing, chief scientist (CNST). Nanotechnology is also having an increasing impact on healthcare, with progress in drug delivery, biomaterials, imaging, diagnostics, active implants and other therapeutic applications. The biggest current concern is the health threats of nanoparticles, which can easily enter body via airways or skin. Construction workers exposed to nanopollutants face increased health risks.

The report was co-produced by Springer Nature, National Center for Nanoscience and Technology (NCNST) and the National Science Library of the Chinese Academy of Sciences (CAS).

Source: http://www.shanghaidaily.com/

Regular Hydrogen Electric Bus Lines Will Open In 2019

Koningshooikt – Van Hool, the independent Belgian bus, coach and industrial vehicle manufacturer has won a contract in Pau, France, to supply 8 Exqui.Cities, known as “tram-buses“, powered by hydrogen. The use of hydrogen buses is not only a first for France it is also a world first for a full BRT (Bus Rapid Transit) system with 18-metre-long articulated tram-buses. This is the first time that hydrogen technology has been integrated as a power source in a tram-bus.

The brand new vehicle is an 18.62 metre-long articulated tram-bus with a 125 passenger capacity and an autonomy of around 300 km. The order of 8 Exqui.Cities will be delivered to the SMTU-PPP (Syndicat Mixte de Transports urbains – Pau Portes des Pyrénées) and the STAP (Société de Transport de l’Agglomération Paloise) in the second half of 2019.

The bus’s power source is an electric hybrid. On the one hand hydrogen (H2) and oxygen (O2) are converted to electricity in the fuel cell using electrolysis in “real time” and, on the other hand, the lithium batteries and electric motors provide additional power wherever and whenever it is needed. The energy that is released when the vehicle’s brakes are applied is also re-used. The use of this technology results in the 0-emission of greenhouse gases or air polluting substances. The vehicle’s only emission is water vapour.

Additional advantages offered by hydrogen buses include their autonomy of over three hundred kilometres and fast re-fuelling (10 minutes). These buses therefore allow bus companies to reach the highest level of operational flexibility and productivity.

Source: http://www.vanhool.be/

Electric Car: More Silicon To Enhance Batteries

Silicon – the second most abundant element in the earth’s crust – shows great promise in Li-ion batteries, according to new research from the University of Eastern Finland. By replacing graphite anodes with silicon, it is possible to quadruple anode capacity.

In a climate-neutral society, renewable and emission-free sources of energy, such as wind and solar power, will become increasingly widespread. The supply of energy from these sources, however, is intermittent, and technological solutions are needed to safeguard the availability of energy also when it’s not sunny or windy. Furthermore, the transition to emission-free energy forms in transportation requires specific solutions for energy storage, and lithium-ion batteries are considered to have the best potential.

Researchers from the University of Eastern Finland introduced new technology to Li-ion batteries by replacing graphite used in anodes by silicon. The study analysed the suitability of electrochemically produced nanoporous silicon for Li-ion batteries. It is generally understood that in order for silicon to work in batteries, nanoparticles are required, and this brings its own challenges to the production, price and safety of the material. However, one of the main findings of the study was that particles sized between 10 and 20 micrometres and with the right porosity were in fact the most suitable ones to be used in batteries. The discovery is significant, as micrometre-sized particles are easier and safer to process than nanoparticles. This is also important from the viewpoint of battery material recyclability, among other things.

In our research, we were able to combine the best of nano– and micro-technologies: nano-level functionality combined with micro-level processability, and all this without compromising performance,” Researcher Timo Ikonen from the University of Eastern Finland says. “Small amounts of silicon are already used in Tesla’s batteries to increase their energy density, but it’s very challenging to further increase the amount,” he continues.

Next, researchers will combine silicon with small amounts of carbon nanotubes in order to further enhance the electrical conductivity and mechanical durability of the material.

The findings were published in Scientific Reports .

Source: http://news.cision.com/