and energy between the drop and the surface, Varanasi says. f you can get the drops to bounce faster,
For example, the turbine blades in electric power plants become less efficient if water builds up on their surfaces. f you can make the blades stay dry longer,
The research received support from the Defense Advanced Research Projects Agency, the MIT Energy Initiative, the National Science Foundation,
When an earthquake and tsunami struck Japan Fukushima nuclear power plant in 2011, knocking out emergency power supplies,
crews sprayed seawater on the reactors to cool them to no avail. One possible reason:
and nuclear engineering at Rensselaer Polytechnic institute who was involved not in this research, says, xtending the surface temperature at which this phenomenon occurs is a challenging task that has been a century-long research effort.
The research was supported by a Young Faculty Award from the Defense Advanced Research Projects Agency, the MIT Energy Initiative,
To help figure that out the researchers created a form of cisplatin targeted to go to mitochondria cell organelles that generate energy.
or battery packs, or other equipment, which the mobile cubes could transport. n the vast majority of other modular systems,
Knowing that about 82 percent of Tanzanians more than 35 million households live off-grid, GCS began going to the villages and selling solar-powered lamps, which also charge cellphones.
GCS alone has provided more than $4 million in energy savings since it started selling solar lanterns three years ago.
Now MIT spinout Essess is bringing similar rive-byinnovations to energy efficiency in homes and businesses.
and foundations to help owners curb energy loss. About the size of a large backpack, Essessrig includes several long-wave infrared radiometric cameras and near-infrared cameras.
which households leak the most energy and, among those, which owners are most likely to make fixes,
But the startup also works with the U s. Department of defense to help identify energy-wasting buildings on their bases.
Revving up Essess Traditional energy audits usually involve sending one employee to a home to manually scan and record leaks.
Essess President and CEO Tom Scaramellino says. t not just figuring out who the worst culprits are who wasting the most energy
because there are customers that can be wasting energy, but theyl never fix it, he says. here the actual energy waste and the psychological component to do something about it.
Those are two distinct analyses we layer on top of one another. Results for utilities companies indicate for instance, which zip codes have homes with the most leaky attics and, among those,
which eat up about 50 percent of energy used in homes and buildings. HVAC system efficiency is affected by the system itself, by household behavioral factors such as thermostat and window usage and
Light interaction with graphene produces particles called plasmons while light interacting with hbn produces phonons.
the plasmons and phonons can couple, producing a strong resonance. The properties of the graphene allow precise control over light,
an ion crystal essentially, a grid of charged atoms in order to study friction effects, atom by atom.
and then there suddenly a catastrophic release of energy. he group continued to stretch and squeeze the ion crystal to manipulate the arrangement of atoms,
however, will require extremely low-power sensors that can run for months without battery changes or, even better,
that can extract energy from the environment to recharge. Last week, at the Symposia on VLSI Technology And circuits, MIT researchers presented a new power converter chip that can harvest more than 80 percent of the energy trickling into it
even at the extremely low power levels characteristic of tiny solar cells. Previous ultralow-power converters that used the same approach had efficiencies of only 40 or 50 percent.
Moreover, the researcherschip achieves those efficiency improvements while assuming additional responsibilities. Where most of its ultralow-power predecessors could use a solar cell to either charge a battery
or directly power a device, this new chip can do both, and it can power the device directly from the battery.
All of those operations also share a single inductor the chip main electrical component which saves on circuit board space
the chip power consumption remains low. e still want to have battery-charging capability, and we still want to provide a regulated output voltage,
Ups and downs The circuit chief function is to regulate the voltages between the solar cell, the battery,
If the battery operates for too long at a voltage that either too high or too low, for instance, its chemical reactants break down,
since the rate at which it dissipates energy as heat is proportional to the square of the current.
and falls depends on the voltage generated by the solar cell, which is highly variable. So the timing of the switch throws has to vary, too.
whose selection is determined by the solar cell voltage. Once again, when the capacitor fills, the switches in the inductor path are flipped. n this technology space,
because there a fixed amount of energy that consumed by doing the work, says Brett Miwa,
#New manufacturing approach slices lithium-ion battery cost in half An advanced manufacturing approach for lithium-ion batteries, developed by researchers at MIT and at a spinoff company called 24m,
promises to significantly slash the cost of the most widely used type of rechargeable batteries while also improving their performance
says Yet-Ming Chiang, the Kyocera Professor of Ceramics at MIT and a cofounder of 24m (and previously a cofounder of battery company A123).
The existing process for manufacturing lithium-ion batteries, he says, has changed hardly in the two decades
In this so-called low battery, the electrodes are suspensions of tiny particles carried by a liquid
and pumped through various compartments of the battery. The new battery design is a hybrid between flow batteries and conventional solid ones:
In this version, while the electrode material does not flow, it is composed of a similar semisolid, colloidal suspension of particles.
Chiang and Carter refer to this as a emisolid battery. impler manufacturing processthis approach greatly simplifies manufacturing,
and also makes batteries that are flexible and resistant to damage, says Chiang, who is senior author of a paper in the Journal of Power Sources analyzing the tradeoffs involved in choosing between solid
and flow-type batteries, depending on their particular applications and chemical components. This analysis demonstrates that
while a flow battery system is appropriate for battery chemistries with a low energy density (those that can only store a limited amount of energy for a given weight),
for high-energy density devices such as lithium-ion batteries, the extra complexity and components of a flow system would add unnecessary extra cost.
Almost immediately after publishing the earlier research on the flow battery, Chiang says, e realized that a better way to make use of this flowable electrode technology was to reinvent the lithium ion manufacturing process. nstead of the standard method of applying liquid coatings to a roll of backing material,
thicker electrodes, the system reduces the conventional battery architecture number of distinct layers, as well as the amount of nonfunctional material in the structure, by 80 percent.
Bendable and foldablein addition to streamlining manufacturing enough to cut battery costs by half, Chiang says,
the new system produces a battery that is more flexible and resilient. While conventional lithium-ion batteries are composed of brittle electrodes that can crack under stress
the new formulation produces battery cells that can be bent, folded or even penetrated by bullets without failing.
This should improve both safety and durability, he says. The company has made so far about 10,000 batteries on its prototype assembly lines, most
of which are undergoing testing by three industrial partners, including an oil company in Thailand and Japanese heavy-equipment manufacturer IHI Corp. The process has received eight patents
The company is initially focusing on grid-scale installations, used to help smooth out power loads
By 2020, Chiang estimates that 24m will be able to produce batteries for less than $100 per kilowatt-hour of capacity.
when is it better to build a flow battery versus a static model. This paper will serve as a key tool for making design choices
and go-no go decisions. iswanathan adds that 24m new battery design ould do the same sort of disruption to lithium ion batteries manufacturing as
#Tiny wires could provide a big energy boost Wearable electronic devices for health and fitness monitoring are a rapidly growing area of consumer electronics;
one of their biggest limitations is the capacity of their tiny batteries to deliver enough power to transmit data.
and release electrical power in such bursts, which are needed for brief transmissions of data from wearable devices such as heart-rate monitors, computers,
At the moment, the coin-sized batteries used in many small electronic devices have limited very ability to deliver a lot of power at once,
Small batteries are suited generally poorly for such power needs, he adds. e know it a problem experienced by a number of companies in the health-monitoring
So an alternative is to go to a combination of a battery and a capacitor, Hunter says:
the battery for long-term, low-power functions, and the capacitor for short bursts of high power. Such a combination should be able to either increase the range of the device,
The new nanowire-based supercapacitor exceeds the performance of existing batteries, while occupying a very small volume. f youe got an Apple Watch and
because other energy storage technologies such as fuel cells, batteries, and flywheels tend to be less efficient, or simply too complex to be reduced practical
it would be desirable to have a high volumetric power density (the amount of power stored in a given volume) and high volumetric energy density (the amount of energy in a given volume).
However, with the new device, e have fairly high volumetric power density, medium energy density, and a low cost, a combination that could be well suited for many applications.
high-quality fuels from low-quality oil New findings released by MIT researchers could help energy companies implement a long-recognized process for converting heavy, high-sulfur crude oil into high-value,
cleaner fuels such as gasoline without using hydrogen a change that would reduce costs, energy use, and carbon dioxide emissions.
and water to promote the desired reactions critical guidance for the design of commercial-scale reactors.
More than a third of the world energy needs are met using oil, and our reliance on that convenient, high-energy density resource will likely continue for decades to come, especially in the transportation sector.
But converting crude oil into lightweight, clean-burning, high-quality fuels such as gasoline, diesel, and jet fuel is getting harder.
and desulfurize heavy crude oil are expensive and energy-intensive, and they require hydrogen, which companies typically produce from natural gas a high-cost process that consumes valuable gas resources
Combining those new insights, the researchers are developing new computational tools to help guide energy companies that want to implement the new process. esting designs
In both cases, they removed samples from their reactor vessel at regular intervals up to 30 minutes.
and how much energy is needed to start them. By knowing those nergy barriers, the researchers can determine the reaction rates under different operating conditions critical information for the overall model of the process.
Knowing what those conditions are inside a practical reactor is a parallel challenge. When oil is injected into flowing SCW,
and energy transfer between streams of fluids. But with supercritical fluids key parameters such as viscosity and density are in ranges not seen under normal (non-supercritical) conditions.
This research was supported by Saudi Aramco, a founding member of the MIT Energy Initiative
#New study shows how nanoparticles can clean up environmental pollutants Many human-made pollutants in the environment resist degradation through natural processes,
citing its potential to reduce worldwide energy consumption. Now MIT spinout Cambridge Electronics Inc. CEI) has announced a line of Gan transistors and power electronic circuits that promise to cut energy usage in data centers, electric cars,
and consumer devices by 10 to 20 percent worldwide by 2025. Power electronics is a ubiquitous technology used to convert electricity to higher or lower voltages and different currents such as in a laptop power adapter
or in electric substations that convert voltages and distribute electricity to consumers. Many of these power-electronics systems rely on silicon transistors that switch on
and off to regulate voltage but, due to speed and resistance constraints, waste energy as heat. CEI Gan transistors have at least one-tenth the resistance of such silicon-based transistors, according to the company.
This allows for much higher energy-efficiency, and orders-of-magnitude faster switching frequency meaning power-electronics systems with these components can be made much smaller.
CEI is using its transistors to enable power electronics that will make data centers less energy-intensive
and to really make an impact on how energy is used in the world, says CEI cofounder Tomás Palacios,
Currently, these data centers eat up about 2 percent of electricity in the United states. But Gan-based power electronics
These are in the chargers that charge the battery, and the inverters that convert the battery power to drive the electric motors.
The silicon transistors used today have constrained a power capability that limits how much power the car can handle.
#New technique helps probe performance of organic solar cell materials A research team led by North carolina State university has developed a new technique for determining the role that a material's structure has on the efficiency of organic solar cells
There have been a lot of studies looking at the efficiency of organic solar cells but the energy conversion process involves multiple steps
#and it's difficult to isolate the efficiency of each step says Dr. Brendan O'connor an assistant professor of mechanical engineering at NC State and senior author of a paper on the work.
Broadly speaking organic solar cells convert light into electric current in four steps. First the cell absorbs sunlight which excites electrons in the active layer of the cell.
In previous organic solar cell research there was ambiguity about whether differences in efficiency were due to dissociation or charge collection#because there was no clear method for distinguishing between the two.
so that it runs parallel to the long axis of organic solar cell molecules it will be absorbed; but if the light runs perpendicular to the molecules it passes right through it.
The researchers created highly organized nanostructures within a portion of the active layer of an organic solar cell meaning that the molecules in that portion all ran the same way.
or just the disorganized section#even though they were on the same active layer of the same solar cell.
and nanostructure features are needed to advance organic solar cell technology. Explore further: Hybrid materials could smash the solar efficiency ceiling More information:
Awartani O. Kudenov M. W. Kline R. J. and O'connor B. T. 2015) In-Plane Alignment in Organic solar cells to Probe the Morphological Dependence of Charge Recombination.
A similar effect can be realized at a much smaller scale by using arrays of metallic nanostructures since light of certain wavelengths excites collective oscillations of free electrons known as plasmon resonances in such structures.
The plasmon resonance wavelength varies sensitively with the dimensions of the nanostructures. Consequently by varying the diameter of the four aluminum nanodisks in a pixel (all four nanodisks having the same diameter) the scientists were able to produce about 15 distinct colors#a good start
The collaborating group from Rensselaer Polytechnic institute is led by Diana Borca-Tasciuc, associate professor of mechanical, aerospace and nuclear engineering.
#Carbon nanotube finding could lead to flexible electronics with longer battery life University of Wisconsin-Madison materials engineers have made a significant leap toward creating higher-performance electronics with improved battery lifend the ability
#Researchers create novel nanobowl optical concentrator for organic solar cell Geometrical light trapping is a simple and promising strategy to largely improve the optical absorption and efficiency of solar cells.
Meanwhile light trapping by nano-textured substrate is an appealing strategy to improve solar cell efficiency.
The novel nanobowl optical concentrator developed by Professor Zhiyong Fan can largely enhance the optical absorption in the active layer of organic solar cell
In addition they have investigated the effect of geometry of nanobowl on the solar cell performance and three types of nanobowl with pitch of 1000 nm 1200 nm and 1500 nm were studied.
Solar cells based on nanobowl with pitch of 1000 nm exhibited the best photon absorption in photoactive layer leading to the highest short-circuit current density of 9. 41 ma cm-2 among all nanobowl substrates.
With open-circuit voltage of 0. 573 V and fill factor of 57.9%this nanobowl solar cell achieved a solar energy conversion efficiency of 3. 12
and Professor He (Henry) Yan who are working on cutting-edge researches about organic photovoltaics. The research project was supported by General Research Funds from Hong kong Research Grants Council and Hong kong Innovation Technology Commission.
Imec demonstrates organic photovoltaics modules showing excellent optical properties high efficiencies More information: Nanobowl optical concentrator for efficient light trapping and high-performance organic photovoltaics.
Science Bulletin. DOI: 10.1007/s11434-014-0693
#Carbon nanoballs can greatly contribute to sustainable energy supply Researchers at Chalmers University of Technology have discovered that the insulation plastic used in high-voltage cables can withstand a 26 per cent higher voltage
if nanometer-sized carbon balls are added. This could result in enormous efficiency gains in the power grids of the future,
which are needed to achieve a sustainable energy system. The renewable energy sources of tomorrow will often be found far away from the end user.
Solar energy will have the greatest impact on the European energy system if focus is on transport of solar power from North africa and Southern Europe to Northern europe."
"Reducing energy losses during electric power transmission is one of the most important factors for the energy systems of the future,
Carbon nanoballs can greatly contribute to sustainable energy supply An electrical tree, which is a major electrical breakdown mechanism of insulation plastic.
Carbon nanoballs can greatly contribute to sustainable energy supply Wind turbines are most effective when placed out at sea.
the researchers tested a number of molecules that are used also within organic solar cell research at Chalmers.
whether the crystalline structure of the materials is mismatched-lowering the manufacturing cost for a wide variety of semiconductor devices such as solar cells lasers and LEDS.
For example in photonic devices like solar cells lasers and LEDS the junction is where photons are converted into electrons or vice versa.
and that a minimum of energy is lost during the transfer. To do that in conventional semiconductor junctions the crystalline structures of both materials need to match.
This manufacturing cost is a major reason why semiconductor devices such as solar cells lasers and LEDS remain very expensive.
#Scalable growth of high quality bismuth nanowires Bismuth nanowires have intriguing electronic and energy harvesting application possibilities.
and Barry Rand an assistant professor of electrical engineering and the Andlinger Center for Energy and the Environment.
Heterostructured nanoparticles can be used as catalysts and in advanced energy conversion and storage systems. Typically these nanoparticles are created from tiny seeds of one material on top of
#Nanoparticle network could bring fast-charging batteries (Phys. org) A new electrode design for lithium-ion batteries has been shown to potentially reduce the charging time from hours to minutes by replacing the conventional graphite electrode with a network of tin-oxide nanoparticles.
Batteries have called two electrodes an anode and a cathode. The anodes in most of today's lithium-ion batteries are made of graphite.
The theoretical maximum storage capacity of graphite is limited very at 372 milliamp hours per gram hindering significant advances in battery technology said Vilas Pol an associate professor of chemical engineering at Purdue University.
The researchers have performed experiments with a porous interconnected tin-oxide based anode which has nearly twice the theoretical charging capacity of graphite.
Findings are detailed in a paper published in November in the journal Advanced Energy Materials.
and contract or breathe during the charge-discharge battery cycle. These spaces are very important for this architecture said Purdue postdoctoral research associate Vinodkumar Etacheri.
Without the proper pore size and interconnection between individual tin oxide nanoparticles the battery fails. The research paper was authored by Etacheri;
#Toward a low-cost'artificial leaf'that produces clean hydrogen fuel For years scientists have been pursuing artificial leaf technology a green approach to making hydrogen fuel that copies plants'ability to convert sunlight into a form of energy they can use.
and harvest hydrogen is one of the most intriguing ways to achieve clean energy. Automakers have started introducing hydrogen fuel cell vehicles
But making hydrogen which mostly comes from natural gas requires electricity from conventional carbon dioxide-emitting power plants.
Producing hydrogen at low cost from water using the clean energy from the sun would make this form of energy
thus saving energy. Furthermore, as opposed to other methods no expensive devices are required. The film with the nanochannels is placed merely in the precipitation bath."
not much material is needed for microsensors, miniature through-flow reactors, or other potential applications. Ensinger's team has tested already successfully one use of the gold nanotubes:
The gold nanotubes conduct electricity especially well due to their one-dimensional structure. In addition, they are relatively long
The result was achieved by improving selective wire-growth processes to produce one nanowire of controlled diameter per mask-grid opening over a range of diameters from 100 nm to 200 nm.
#Lengthening the life of high capacity silicon electrodes in rechargeable lithium batteries A new study will help researchers create longer-lasting higher-capacity lithium rechargeable batteries
In a study published in the journal ACS Nano researchers showed how a coating that makes high capacity silicon electrodes more durable could lead to a replacement for lower-capacity graphite electrodes.
Understanding how the coating works gives us an indication of the direction we need to move in to overcome the problems with silicon electrodes said materials scientist Chongmin Wang of the Department of energy's Pacific Northwest National Laboratory.
Thanks to its high electrical capacity potential silicon is one of the hottest things in lithium ion battery development these days Replacing the graphite electrode in rechargeable lithium batteries with silicon could increase the capacity tenfold making
Silicon electrodes aren't very durable#after a few dozen recharges they can no longer hold electricity. That's partly due to how silicon takes up lithium#like a sponge.
and thoroughly#an improvement over earlier silicon electrodes#but only partly alleviates the fracturing problem. Last year materials scientist Chunmei Ban and her colleagues at the National Renewable energy Laboratory in Golden Colorado and the University of Colorado Boulder found that they could cover silicon nanoparticles with a rubberlike coating made from aluminum glycerol.
Ban's group#which developed the coating for silicon electrodes called alucone and is currently the only group that can create alucone-coated silicon particles#took high magnification images of the particles in an electron microscope.
and limits how much lithium the particle can take in when a battery charges. At the same time they found that the alucone coating softens the particles making it easier for them to expand
Silicon sponge improves lithium-ion battery performance More information: Yang He Daniela Molina Piper Menggu Jonathan J. Travis Steven M. George Se-Hee Lee Arda Genc Lee Pullan Jun Liu
In situ Transmission Electron microscopy Probing of Native Oxide and Artificial Layers on Silicon Nanoparticles for Lithium ion batteries ACS Nano October 27 2014 DOI:
However it will provide an environmentally friendly low-cost way to make nanoporous graphene for use in supercapacitors-devices that can store energy and release it rapidly.
The findings were published just in Nano Energy by scientists from the OSU College of Science OSU College of Engineering Argonne National Laboratory the University of South Florida and the National Energy technology Laboratory in Albany Ore.
and nanoporous graphene a pure form of carbon that's remarkably strong and can efficiently conduct heat and electricity.
A supercapacitor is a type of energy storage device but it can be recharged much faster than a battery
and has a great deal more power. They are used mostly in any type of device where rapid power storage
and short but powerful energy release is needed. They are being used in consumer electronics and have applications in heavy industry with the ability to power anything from a crane to a forklift.
A supercapacitor can capture energy that might otherwise be wasted such as in braking operations. And their energy storage abilities may help smooth out the power flow from alternative energy systems such as wind energy.
They can power a defibrillator open the emergency slides on an aircraft and greatly improve the efficiency of hybrid electric automobiles.
Nanoporous carbon materials can also adsorb gas pollutants work as environmental filters or be used in water treatment.
Process turns cellulose into energy storage device e
#Nanotubes may restore sight to blind retinas The aging process affects everything from cardiovascular function to memory to sexuality.
which require wiring to outside energy or light sources this is a groundbreaking new direction. The research team received funding for their study from the Israel Ministry of Science and Technology the European Research Council and the Biotechnology and Biological sciences Research Council.
Published in the journal Nature the discovery could revolutionize fuel cells and other hydrogen-based technologies as they require a barrier that only allow protons-hydrogen atoms stripped off their electrons-to pass through.
which are at the heart of modern fuel cell technology. Fuel cells use oxygen and hydrogen as a fuel and convert the input chemical energy directly into electricity.
Without membranes that allow an exclusive flow of protons but prevent other species to pass through this technology would not exist.
This can boost competitiveness of fuel cells. The Manchester group also demonstrated that their one-atom-thick membranes can be used to extract hydrogen from a humid atmosphere.
They hypothesise that such harvesting can be combined together with fuel cells to create a mobile electric generator that is fuelled simply by hydrogen present in air.
This hydrogen can then be burned in a fuel cell. We worked with small membranes and the achieved flow of hydrogen is of course tiny so far.
Because graphene can be produced these days in square metre sheets we hope that it will find its way to commercial fuel cells sooner rather than later r
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