Tag Archives: power plants

Cancer-killing nanoparticles sneak through defenses camouflaged in tumor cells

Researchers at Penn State have camouflaged drug-delivering nanoparticles by wrapping them inside cancer cells

Cancer has a few tricks up its sleeve to defend itself from the body’s immune system, but a new therapy designed by researchers at Penn State has now turned one of those tactics against it. The team camouflaged a cancer-killing drug using cells from the tumor itself, allowing them to sneak medicine past the tumor’s defenses like a nanoscale Trojan horse and deliver a killing blow from the inside.

..
Continue Reading Cancer-killing nanoparticles sneak through defenses camouflaged in tumor cells

Category: Medical

Tags:

Related Articles:

Clean water could be zapped out of power plant steam

There's potable water in that thar steam

Approximately 39 percent of all water drawn from US rivers, lakes and reservoirs is used to cool electric power plants. Much of that water, in turn, ends up going out those plants’ cooling towers in the form of steam. A new system created at MIT, however, could convert that steam into clean drinking water.

..
Continue Reading Clean water could be zapped out of power plant steam

Category: Good Thinking

Tags:

Related Articles:

Closing power plants cuts rate of preterm baby births

Closing coal- and oil-fired power plants lowers the rate of preterm births in neighboring communities and improves fertility, two new studies show.

Researchers compared preterm births and fertility before and after eight power plants in California closed between 2001 and 2011.

“We were excited to do a good news story in environmental health…”

Overall, the percentage of preterm births—babies born before 37 weeks of gestation—dropped from 7 percent in a year-long period before plant closure to 5.1 percent for the year after shutdown. Rates for non-Hispanic African-American, and Asian women dropped even more: from 14.4 percent to 11.3 percent.

Preterm births, which can often result in babies spending time in a neonatal intensive care unit, contributes to infant mortality and can cause health problems later in life.

The World Health Organization estimates that the cost of preterm births, defined as births between 32 and 37 weeks of gestation, accounts for some $2 billion in healthcare costs worldwide.

The 20-25 percent drop in preterm birthrates is larger than expected, but consistent with other studies linking birth problems to air pollution around power plants, says Joan Casey, a postdoctoral fellow at the University of California, Berkeley, and lead author of a study in the American Journal of Epidemiology.

Researchers used similar data for a paper in Environmental Health and found that fertility—the number of live births per 1,000 women—increased around coal and oil power plants after closure.

“We were excited to do a good news story in environmental health,” Casey says. “Most people look at air pollution and adverse health outcomes, but this is the flip side: We said, let’s look at what happens when we have this external shock that removes air pollution from a community and see if we can see any improvements in health.”

The findings could help policy makers more strategically plan the decommissioning of power plants as they build more renewable sources of energy, in order to have the biggest health impact.

“We believe that these papers have important implications for understanding the potential short-term community health benefits of climate and energy policy shifts and provide some very good news on that front,” says coauthor Rachel Morello-Frosch, professor of environmental science, policy, and management; of public health; and a leading expert on the differential effects of pollution on communities of color and the poor.

“These studies indicate short-term beneficial impacts on preterm birth rates overall and particularly for women of color.”

Researchers compared preterm birth rates in the first year following the closure date of each power plant with the rate during the year starting two years before the plant’s retirement, so as to eliminate seasonal effects on preterm births. They also corrected for the mother’s age, socioeconomic status, education level, and race/ethnicity.

Dividing the surrounding region into three concentric rings 5 kilometers (3 miles) wide, Casey delved into state of California birth records to determine the rate of preterm births in each ring.

Those living in the closest ring, from zero to 5 kilometers from the plant, saw the largest improvement: a drop from 7 to 5.1 percent. Those living in the 5-10 kilometer zone showed less improvement. The researchers used those living in the 10-20 km zone as a control population.

Toxic ponds near these U.S. power plants are leaking

Researchers also considered the effects of winds on preterm birth rates, and though downwind areas seemed to exhibit greater improvements, the differences were not statistically significant.

As a control, they replicated their analysis around eight power plants that had not closed, and found no before-versus-after difference, which supported the results of their main analyses.

There did not appear to be any effect on births before 32 weeks, which Casey says may reflect the fact that very early births are a result of problems, genetic or environmental, more serious than air pollution.

Casey notes that the study didn’t break out the effects of individual pollutants, which can include particulate matter, sulfur dioxide, nitrogen oxides, benzene, lead, mercury, and other known health hazards, but took a holistic approach to assess the combined effect of a mix of pollutants.

“It would be good to look at this relationship in other states and see if we can apply a similar rationale to retirement of power plants in other places,” Casey says.

Air pollution tied to higher risk of abnormal fetal growth

Other coauthors are from UC Berkeley, Johns Hopkins University Bloomberg School of Public Health, and UC San Francisco.

The UC San Francisco California Preterm Birth Initiative, which is funded by Marc and Lynne Benioff, the National Institute of Environmental Health Sciences, and the US Environmental Protection Agency funded the work.

Source: UC Berkeley

The post Closing power plants cuts rate of preterm baby births appeared first on Futurity.

Closing power plants cuts rate of preterm baby births

Closing coal- and oil-fired power plants lowers the rate of preterm births in neighboring communities and improves fertility, two new studies show.

Researchers compared preterm births and fertility before and after eight power plants in California closed between 2001 and 2011.

“We were excited to do a good news story in environmental health…”

Overall, the percentage of preterm births—babies born before 37 weeks of gestation—dropped from 7 percent in a year-long period before plant closure to 5.1 percent for the year after shutdown. Rates for non-Hispanic African-American, and Asian women dropped even more: from 14.4 percent to 11.3 percent.

Preterm births, which can often result in babies spending time in a neonatal intensive care unit, contributes to infant mortality and can cause health problems later in life.

The World Health Organization estimates that the cost of preterm births, defined as births between 32 and 37 weeks of gestation, accounts for some $2 billion in healthcare costs worldwide.

The 20-25 percent drop in preterm birthrates is larger than expected, but consistent with other studies linking birth problems to air pollution around power plants, says Joan Casey, a postdoctoral fellow at the University of California, Berkeley, and lead author of a study in the American Journal of Epidemiology.

Researchers used similar data for a paper in Environmental Health and found that fertility—the number of live births per 1,000 women—increased around coal and oil power plants after closure.

“We were excited to do a good news story in environmental health,” Casey says. “Most people look at air pollution and adverse health outcomes, but this is the flip side: We said, let’s look at what happens when we have this external shock that removes air pollution from a community and see if we can see any improvements in health.”

The findings could help policy makers more strategically plan the decommissioning of power plants as they build more renewable sources of energy, in order to have the biggest health impact.

“We believe that these papers have important implications for understanding the potential short-term community health benefits of climate and energy policy shifts and provide some very good news on that front,” says coauthor Rachel Morello-Frosch, professor of environmental science, policy, and management; of public health; and a leading expert on the differential effects of pollution on communities of color and the poor.

“These studies indicate short-term beneficial impacts on preterm birth rates overall and particularly for women of color.”

Researchers compared preterm birth rates in the first year following the closure date of each power plant with the rate during the year starting two years before the plant’s retirement, so as to eliminate seasonal effects on preterm births. They also corrected for the mother’s age, socioeconomic status, education level, and race/ethnicity.

Dividing the surrounding region into three concentric rings 5 kilometers (3 miles) wide, Casey delved into state of California birth records to determine the rate of preterm births in each ring.

Those living in the closest ring, from zero to 5 kilometers from the plant, saw the largest improvement: a drop from 7 to 5.1 percent. Those living in the 5-10 kilometer zone showed less improvement. The researchers used those living in the 10-20 km zone as a control population.

Toxic ponds near these U.S. power plants are leaking

Researchers also considered the effects of winds on preterm birth rates, and though downwind areas seemed to exhibit greater improvements, the differences were not statistically significant.

As a control, they replicated their analysis around eight power plants that had not closed, and found no before-versus-after difference, which supported the results of their main analyses.

There did not appear to be any effect on births before 32 weeks, which Casey says may reflect the fact that very early births are a result of problems, genetic or environmental, more serious than air pollution.

Casey notes that the study didn’t break out the effects of individual pollutants, which can include particulate matter, sulfur dioxide, nitrogen oxides, benzene, lead, mercury, and other known health hazards, but took a holistic approach to assess the combined effect of a mix of pollutants.

“It would be good to look at this relationship in other states and see if we can apply a similar rationale to retirement of power plants in other places,” Casey says.

Air pollution tied to higher risk of abnormal fetal growth

Other coauthors are from UC Berkeley, Johns Hopkins University Bloomberg School of Public Health, and UC San Francisco.

The UC San Francisco California Preterm Birth Initiative, which is funded by Marc and Lynne Benioff, the National Institute of Environmental Health Sciences, and the US Environmental Protection Agency funded the work.

Source: UC Berkeley

The post Closing power plants cuts rate of preterm baby births appeared first on Futurity.

Water-based battery stores green energy for later

A new water-based battery could provide a cheap way to store wind or solar energy for later, researchers say.

The battery stores energy generated when the sun is shining and wind is blowing so it can be fed back into the electric grid and redistributed when demand is high.

The prototype manganese-hydrogen battery, reported in Nature Energy, stands just three inches tall and generates a mere 20 milliwatt hours of electricity, which is on par with the energy levels of LED flashlights that hang on a key ring.

Despite the prototype’s diminutive output, the researchers are confident they can scale up this table-top technology to an industrial-grade system that could charge and recharge up to 10,000 times, creating a grid-scale battery with a useful lifespan well in excess of a decade.

Yi Cui, a professor of materials science at Stanford University and senior author of the paper, says manganese-hydrogen battery technology could be one of the missing pieces in the nation’s energy puzzle—a way to store unpredictable wind or solar energy so as to lessen the need to burn reliable but carbon-emitting fossil fuels when the renewable sources aren’t available.

“What we’ve done is thrown a special salt into water, dropped in an electrode, and created a reversible chemical reaction that stores electrons in the form of hydrogen gas,” Cui says.

Clever chemistry

Wei Chen, a postdoctoral scholar in Cui’s lab, led the team that dreamed up the concept and built the prototype. In essence, the researchers coaxed a reversible electron-exchange between water and manganese sulfate, a cheap, abundant industrial salt used to make dry cell batteries, fertilizers, paper, and other products.

To mimic how a wind or solar source might feed power into the battery, the researchers attached a power source to the prototype. The electrons flowing in reacted with the manganese sulfate dissolved in the water to leave particles of manganese dioxide clinging to the electrodes. Excess electrons bubbled off as hydrogen gas, storing that energy for future use.

Engineers know how to re-create electricity from the energy stored in hydrogen gas so the important next step was to prove that they can recharge the water-based battery.

The researchers did this by re-attaching their power source to the depleted prototype, this time with the goal of inducing the manganese dioxide particles clinging to the electrode to combine with water, replenishing the manganese sulfate salt. Once this process restored the salt, incoming electrons became surplus, and excess power could bubble off as hydrogen gas, in a method that can be repeated again and again and again.

Cui estimates that, given the water-based battery’s expected lifespan, it would cost a penny to store enough electricity to power a 100-watt lightbulb for twelve hours.

“We believe this prototype technology will be able to meet Department of Energy goals for utility-scale electrical storage practicality,” Cui says.

The Department of Energy (DOE) has recommended batteries for grid-scale storage should store and then discharge at least 20 kilowatts of power over a period of an hour, be capable of at least 5,000 recharges, and have a useful lifespan of 10 years or more. To make it practical, such a battery system should cost $2,000 or less, or $100 per kilowatt hour.

Former DOE secretary and Nobel laureate Steven Chu, now a professor at Stanford, has a longstanding interest in encouraging technologies to help the nation transition to renewable energy.

“While the precise materials and design still need development, this prototype demonstrates the type of science and engineering that suggest new ways to achieve low-cost, long-lasting, utility-scale batteries,” says Chu, who was not a member of the research team.

Powering the grid

According to DOE estimates, about 70 percent of US electricity is generated by coal or natural gas plants, which account for 40 percent of carbon dioxide emissions. Shifting to wind and solar generation is one way to reduce those emissions. But that creates new challenges involving the variability of the power supply. Most obviously, the sun only shines by day and, sometimes, the wind doesn’t blow.

But another less well-understood but important form of variability comes from surges of demand on the grid—that network of high-tension wires that distribute electricity over regions and ultimately to homes. On a hot day, when people come home from work and crank up the air conditioning, utilities must have load-balancing strategies to meet peak demand: some way to boost power generation within minutes to avoid brownouts or blackouts that might otherwise bring down the grid.

3 plans to avoid blackouts using 100% renewable energy

Today, utilities often accomplish this by firing up on-demand or “dispatchable” power plants that may lie idle much of the day but can come online within minutes—producing quick energy but boosting carbon emissions. Some utilities have developed short-term load balancing that does not rely on fossil-fuel burning plants.

The most common and cost-effective such strategy is pumped hydroelectric storage: using excess power to send water uphill, then letting it flow back down to generate energy during peak demand. However, hydroelectric storage only works in regions with adequate water and space. So to make wind and solar more useful, DOE has encouraged high-capacity batteries as an alternative.

Beating the competition

Cui says there are several types of rechargeable battery technologies on the market, but it isn’t clear which approaches will meet DOE requirements and prove their practicality to the utilities, regulators, and other stakeholders who maintain the nation’s electrical grid.

For instance, Cui says rechargeable lithium ion batteries, which store the small amounts of energy needed to run phones and laptops, are based on rare materials and are therefore too pricey to store power for a neighborhood or city. Cui says grid-scale storage requires a low-cost, high-capacity, rechargeable battery. The manganese-hydrogen process seems promising.

“Other rechargeable battery technologies are easily more than five times of that cost over the life time,” Cui adds.

Chen says novel chemistry, low-cost materials and relative simplicity made the manganese-hydrogen battery ideal for low-cost grid-scale deployment.

Sugar cubes solve big problem with lithium metal batteries

The prototype needs development work to prove itself. For one thing, it uses platinum as a catalyst to spur the crucial chemical reactions at the electrode that make the recharge process efficient, and the cost of that component would be prohibitive for large-scale deployment. But Chen says the team is already working on cheaper ways to coax the manganese sulfate and water to perform the reversible electron exchange.

“We have identified catalysts that could bring us below the $100-per-kilowatt-hour DOE target,” he says.

The researchers report doing 10,000 recharges of the prototypes, which is twice the DOE requirements, but say it will be necessary to test the manganese-hydrogen battery under actual electric grid storage conditions in order to truly assess its lifetime performance and cost.

Cui says he has sought to patent the process through the Stanford Office of Technology Licensing and plans to form a company to commercialize the system.

Additional coauthors are from the Chinese Academy of Sciences and Stanford. The Department of Energy funded the research.

Source: Stanford University

The post Water-based battery stores green energy for later appeared first on Futurity.

XPrize's Marcius Extavour on how we can turn our CO2 problem into something useful

XPrize's senior director of energy and resources, Dr Marcius Extavour

Launched in 2015 and yesterday whittled down to 10 finalists, the Carbon XPrize has now progressed to its final, critical stage. The US$20 million contest asks competitors to develop technologies that can capture CO2 emissions from operational power plants and convert them into valuable products, with concrete, plastics and battery components among the potential applications. As these teams prepare to put their technologies to the test under real-world conditions for the first time, New Atlas chatted with XPrize’s senior director of energy and resources Dr Marcius Extavour about the possibilities that they may bring.

..
Continue Reading XPrize’s Marcius Extavour on how we can turn our CO2 problem into something useful

Category: Environment

Tags:

Related Articles:

3 plans to avoid blackouts using 100% renewable energy

Researchers have proposed three different methods for providing consistent power in 139 countries using 100 percent renewable energy.

The inconsistencies of power produced by wind, water, and sunlight and the continuously fluctuating demand for energy often hinder renewable energy solutions. In a new paper, which appears in Renewable Energy, the researchers outline several solutions to making clean power reliable enough for all energy sectors—transportation; heating and cooling; industry; and agriculture, forestry, and fishing—in 20 world regions after all sectors have converted to 100 percent clean, renewable energy.

The researchers previously developed roadmaps for transitioning 139 countries to 100 percent clean, renewable energy by 2050 with 80 percent of that transition completed by 2030. The present study examines ways to keep the grid stable with these roadmaps.

Multiple solutions

“Based on these results, I can more confidently state that there is no technical or economic barrier to transitioning the entire world to 100 percent clean, renewable energy with a stable electric grid at low cost,” says lead author Mark Z. Jacobson, a professor of civil and environmental engineering at Stanford University who is also a senior fellow at the Stanford Precourt Institute for Energy and the Stanford Woods Institute for the Environment.

“This solution would go a long way toward eliminating global warming and the 4 million to 7 million air pollution–related deaths that occur worldwide each year, while also providing energy security.”

“…the greatest barrier to the large-scale implementation of clean renewable energy is people’s perception that it’s too hard to keep the lights on…”

The paper builds on a previous 2015 study by Jacobson and colleagues that examined the ability of the grid to stay stable in the 48 contiguous United States. That study only included one scenario for how to achieve the goals. Some criticized that paper for relying too heavily on adding turbines to existing hydroelectric dams—which the group suggested in order to increase peak electricity production without changing the number or size of the dams.

The previous paper was also criticized for relying too much on storing excess energy in water, ice, and underground rocks. The solutions in the current paper address these criticisms by suggesting several different solutions for stabilizing energy produced with 100 percent clean, renewable sources, including solutions with no added hydropower turbines and no storage in water, ice, or rocks.

“Our main result is that there are multiple solutions to the problem,” says Jacobson. “This is important because the greatest barrier to the large-scale implementation of clean renewable energy is people’s perception that it’s too hard to keep the lights on with random wind and solar output.”

Meeting demand

At the heart of this study is the need to match energy supplied by wind, water, and solar power and storage with what the researchers predict demand to be in 2050. To do this, they grouped 139 countries—for which they created energy roadmaps in a previous study—into 20 regions based on geographic proximity and some geopolitical concerns.

Unlike the previous 139-country study, which matched energy supply with annual-average demand, the present study matches supply and demand in 30-second increments for 5 years (2050-2054) to account for the variability in wind and solar power as well as the variability in demand over hours and seasons.

For the study, the researchers relied on two computational modeling programs. The first program predicted global weather patterns from 2050 to 2054. From this, they further predicted the amount of energy that could be produced from weather-related energy sources like onshore and offshore wind turbines, solar photovoltaics on rooftops, and in power plants, concentrated solar power plants, and solar thermal plants over time. These types of energy sources are variable and don’t necessarily produce energy when demand is highest.

The group then combined data from the first model with a second model that incorporated energy produced by more stable sources of electricity, like geothermal power plants, tidal and wave devices, and hydroelectric power plants, and of heat, like geothermal reservoirs. The second model also included ways of storing energy when there was excess, such as in electricity, heat, cold, and hydrogen storage. Further, the model included predictions of energy demand over time.

With the two models, the group was able to predict both how much energy could be produced through more variable sources of energy, and how well other sources could balance out the fluctuating energy to meet demands.

Keeping the lights on

Scenarios based on the modeling data avoided blackouts at low cost in all 20 world regions for all five years examined and under three different storage scenarios. One scenario includes heat pumps—which are used in place of combustion-based heaters and coolers—but no hot or cold energy storage; two add no hydropower turbines to existing hydropower dams; and one has no battery storage.

The fact that no blackouts occurred under three different scenarios suggests that many possible solutions to grid stability with 100 percent wind, water, and solar power are possible, a conclusion that contradicts previous claims that the grid cannot stay stable with such high penetrations of just renewables.

Overall, the researchers found that the cost per unit of energy—including the cost in terms of health, climate and energy—in every scenario was about one quarter what it would be if the world continues on its current energy path. This is largely due to eliminating the health and climate costs of fossil fuels. Also, by reducing water vapor, the wind turbines included in the roadmaps would offset about 3 percent of global warming to date.

Although the cost of producing a unit of energy is similar in the roadmap scenarios and the non-intervention scenario, the researchers found that the roadmaps roughly cut in half the amount of energy needed in the system. So, consumers would actually pay less.

Green energy is more popular if it’s the default

The vast amount of these energy savings come from avoiding the energy needed to mine, transport, and refine fossil fuels, converting from combustion to direct electricity, and using heat pumps instead of conventional heaters and air conditioners.

“One of the biggest challenges facing energy systems based entirely on clean, zero-emission wind, water, and solar power is to match supply and demand with near-perfect reliability at reasonable cost,” says Mark Delucchi, coauthor of the paper and a research scientist at the University of California, Berkeley. “Our work shows that this can be accomplished, in almost all countries of the world, with established technologies.”

Planning ahead, working together

Jacobson and his colleagues says that a remaining challenge of implementing their roadmaps is that they require coordination across political boundaries.

“Ideally, you’d have cooperation in deciding where you’re going to put the wind farms, where you’re going to put the solar panels, where you’re going to put the battery storage,” says Jacobson. “The whole system is most efficient when it is planned ahead of time as opposed to done one piece at a time.”

Germany’s big push for renewables is paying off

In light of this geopolitical complication, they are also working on smaller roadmaps to help individual towns, many of which have already committed to achieving 100 percent renewable energy.

Additional coauthors of this paper are from Aalborg University in Denmark and UC Berkeley.

Source: Stanford University

The post 3 plans to avoid blackouts using 100% renewable energy appeared first on Futurity.

The Aging Beauty Of Soviet Control Rooms

They look like the sets of glorious sci-fi B-movies.

With their hundreds of buttons, blinking lights, and spartan, Space Age aesthetic, the control rooms of power plants in the old Soviet Union would be the perfect sets for a Flash Gordon movie directed by Stanley Kubrick–which all of the sudden I really wish existed.

Read Full Story

Tiny detector is 1st to see neutrinos bump nucleus

In 1974, a physicist predicted a new way for ghostly particles called neutrinos to interact with matter. More than four decades later, the world’s smallest neutrino detector has observed the elusive interaction for the first time.

Neutrinos are a challenge to study because their interactions with matter are so rare. Particularly elusive has been what’s known as coherent elastic neutrino-nucleus scattering, which occurs when a neutrino bumps off the nucleus of an atom.

Researchers detected the scattering process by using a detector that’s small and lightweight enough for a researcher to carry.

“Why did it take 43 years to observe this interaction?” asks Juan Collar, a physics professor at the University of Chicago and senior member of the Kavli Institute for Cosmological Physics. “What takes place is very subtle.”

At the time, Freedman didn’t see much of a chance for experimental confirmation, writing: “Our suggestion may be an act of hubris, because the inevitable constraints of interaction rate, resolution, and background pose grave experimental difficulties.”

When a neutrino bumps into the nucleus of an atom, it creates a tiny, barely measurable recoil. Making a detector out of heavy elements such as iodine, cesium, or xenon dramatically increases the probability for this new mode of neutrino interaction, compared to other processes. But there’s a trade-off, since the tiny nuclear recoils that result become more difficult to detect as the nucleus grows heavier.

“Imagine your neutrinos are ping-pong balls striking a bowling ball. They are going to impart only a tiny extra momentum to this bowling ball,” Collar says.

To detect that bit of tiny recoil, researchers figured out that a cesium iodide crystal doped with sodium was the perfect material. The discovery led the scientists to jettison the heavy, gigantic detectors common in neutrino research for one similar in size to a toaster.

The 4-inch-by-13-inch detector used to produce the results weighs only 32 pounds (14.5 kilograms). In comparison, the world’s most famous neutrino observatories are equipped with thousands of tons of detector material.

“You don’t have to build a gigantic laboratory around it,” says doctoral student Bjorn Scholz, whose thesis will contain the result reported in Science.

“We can now think about building other small detectors that can then be used, for example to monitor the neutrino flux in nuclear power plants. You just put a nice little detector on the outside, and you can measure it in situ.”

Mysterious particles

Neutrino physicists, meanwhile, are interested in using the technology to better understand the properties of the mysterious particle.

“Neutrinos are one of the most mysterious particles,” Collar says. “We ignore many things about them. We know they have mass, but we don’t know exactly how much.”

Physicist says data from neutrino experiment are ‘gorgeous’

Through measuring coherent elastic neutrino-nucleus scattering, physicists hope to answer such questions. The new paper, for example, imposes limits on new types of neutrino-quark interactions that have been proposed.

The results also have implications in the search for Weakly Interacting Massive Particles. WIMPs are candidate particles for dark matter, which is invisible material of unknown composition that accounts for 85 percent of the mass of the universe.

“What we have observed with neutrinos is the same process expected to be at play in all the WIMP detectors we have been building,” Collar says.

Neutrino alley

The COHERENT Collaboration, which involves 90 scientists at 18 institutions, has been conducting its search for coherent neutrino scattering at the Spallation Neutron Source at Oak Ridge National Laboratory in Tennessee. The researchers installed their detectors in a basement corridor that became known as “neutrino alley.” This corridor is heavily shielded by iron and concrete from the highly radioactive neutron beam target area, only 20 meters (less than 25 yards) away.

‘Ice fishing’ for neutrinos yields new measurements

This neutrino alley solved a major problem for neutrino detection: It screens out almost all neutrons generated by the Spallation Neutron Source, but neutrinos can still reach the detectors. This allows researchers to more clearly see neutrino interactions in their data. Elsewhere they would be easily drowned out by the more prominent neutron detections.

The Spallation Neutron Source generates the most intense pulsed neutron beams in the world for scientific research and industrial development. In the process of generating neutrons, the SNS also produces neutrinos, though in smaller quantities.

“You could use a more sophisticated type of neutrino detector, but not the right kind of neutrino source, and you wouldn’t see this process,” Collar says. “It was the marriage of ideal source and ideal detector that made the experiment work.”

The National Science Foundation, Alfred P. Sloan Foundation, US Department of Energy, and the Kavli Institute for Cosmological Physics funded the work.

Source: University of Chicago

The post Tiny detector is 1st to see neutrinos bump nucleus appeared first on Futurity.

With wireless charging, electric cars could drive forever

Scientists have found a way to wirelessly transmit electricity to a nearby moving object.

The method may have applications in transportation, medical devices, and more. If electric cars could recharge while driving down a highway, for example, it would virtually eliminate concerns about their range and lower their cost, perhaps making electricity the standard fuel for vehicles.

“In addition to advancing the wireless charging of vehicles and personal devices like cellphones, our new technology may untether robotics in manufacturing, which also are on the move,” says Shanhui Fan, a professor of electrical engineering at Stanford University and senior author of the study.

“In theory, one could drive for an unlimited amount of time without having to stop to recharge…”

“We still need to significantly increase the amount of electricity being transferred to charge electric cars, but we may not need to push the distance too much more,” he says.

The group built on existing technology developed in 2007 at MIT for transmitting electricity wirelessly over a distance of a few feet to a stationary object. In the new work, the team transmitted electricity wirelessly to a moving LED lightbulb. That demonstration only involved a 1-milliwatt charge, whereas electric cars often require tens of kilowatts to operate.

The team is now working on greatly increasing the amount of electricity that can be transferred, and tweaking the system to extend the transfer distance and improve efficiency.

Going farther

Wireless charging would address a major drawback of plug-in electric cars—their limited driving range. Tesla Motors expects its upcoming Model 3 to go more than 200 miles on a single charge and the Chevy Bolt, which is already on the market, has an advertised range of 238 miles. But electric vehicle batteries generally take several hours to fully recharge. A charge-as-you-drive system would overcome these limitations.

“In theory, one could drive for an unlimited amount of time without having to stop to recharge,” Fan explains. “The hope is that you’ll be able to charge your electric car while you’re driving down the highway. A coil in the bottom of the vehicle could receive electricity from a series of coils connected to an electric current embedded in the road.”

‘Superlens’ adds range to wireless power transfer

Some transportation experts envision an automated highway system where driverless electric vehicles are wirelessly charged by solar power or other renewable energy sources. The goal would be to reduce accidents and dramatically improve the flow of traffic while lowering greenhouse gas emissions.

Wireless technology could also assist GPS navigation of driverless cars. GPS is accurate up to about 35 feet. For safety, autonomous cars need to be in the center of the lane where the transmitter coils would be embedded, providing very precise positioning for GPS satellites.

Made with magnets

Mid-range wireless power transfer is based on magnetic resonance coupling. Just as major power plants generate alternating currents by rotating coils of wire between magnets, electricity moving through wires creates an oscillating magnetic field.

This field also causes electrons in a nearby coil of wires to oscillate, thereby transferring power wirelessly. The transfer efficiency is further enhanced if both coils are tuned to the same magnetic resonance frequency and are positioned at the correct angle.

However, the continuous flow of electricity can only be maintained if some aspects of the circuits, such as the frequency, are manually tuned as the object moves. So, either the energy transmitting coil and receiver coil must remain nearly stationary, or the device must be tuned automatically and continuously—a significantly complex process.

To address the challenge, the research team eliminated the radio-frequency source in the transmitter and replaced it with a commercially available voltage amplifier and feedback resistor. This system automatically figures out the right frequency for different distances without the need for human interference.

“Adding the amplifier allows power to be very efficiently transferred across most of the three-foot range and despite the changing orientation of the receiving coil,” says graduate student Sid Assawaworrarit, the study’s lead author. “This eliminates the need for automatic and continuous tuning of any aspect of the circuits.”

Assawaworrarit tested the approach by placing an LED bulb on the receiving coil. In a conventional setup without active tuning, LED brightness would diminish with distance.

In the new setup, the brightness remained constant as the receiver moved away from the source by a distance of about three feet. Fan’s team recently filed a patent application for the latest advance.

Panel would turn room into wireless charging station

The group used an off-the-shelf, general-purpose amplifier with a relatively low efficiency of about 10 percent. They say custom-made amplifiers can improve that efficiency to more than 90 percent.

“We can rethink how to deliver electricity not only to our cars, but to smaller devices on or in our bodies,” Fan says. “For anything that could benefit from dynamic, wireless charging, this is potentially very important.”

The TomKat Center for Sustainable Energy at Stanford supported part of the work.

Source: Stanford University

The post With wireless charging, electric cars could drive forever appeared first on Futurity.