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February 1: EVAZ Stakeholder Meeting — Phoenix
February 2, 16: Solar Coach Office Hours, PORA — Sun City West
February 8: EVAZ Policy Working Group — Phoenix
February 28: Clean Cities Legislative Breakfast, State Capitol — Phoenix
March 1, 15, 29: Solar Coach Office Hours, PORA — Sun City West
March 17: Pointe Tapatio Meeting — Phoenix
March 24-25: Anthem Days — Anthem
April 21: Anthem Go Green — Anthem
April 21: Earth Day and Solar Up Cave Creek — Cave Creek
Please contact Aparna P. Mohla at amohla[at]smartpower.org if you would like more information about our events.
Japanese Tech Could Allow Electric Vehicles To Drive Unlimited Distances
BY BEN SCHILLERMon Sep 19, 2011
A road that charges electric cars has long been a pipe dream for combating range anxiety, but these Japanese scientists are making it work in real life.
It’s a well-known shortcoming of electric cars that they can only be driven short distances. The Chevy Volt, for example, has a maximum range of 50 miles on a single charge. And, while it’s possible to back up the electricity system with a fossil fuel-based one, as the Chevy does, that somewhat takes away from the point of having an electric car in the first place.
It would be much better either if the car could go longer without needing to stop, or if it could somehow be recharged mid-flight, like a long-haul military plane. And, in fact, the second possibility may not be as fanciful as you might think.
Researchers at Toyota Central R&D Labs and Toyohashi University of Technology have come up with what they think is the world’s first mid-drive charging system, based on a similar mechanism that allows trains to travel under overhead wires.
Under the still-experimental system, electrified metal plates are buried under roads, which “up-convert” energy via a radio frequency to a steel belt inside a car’s tires, as well as to a plate sitting above the tire.
Although testing of the system has only involved low voltages so far, the researchers say the system could allow to electric cars to be far lighter than they are today. The electric cars would need smaller battery packs, as they would only need to to get and from the electrified highways.
Anything to reduce the weight of today’s electric car batteries would be a good thing, potentially saving energy and conserving limited lithium supplies. The Chevy Volt’s battery assembly weighs a not-insubstantial 435 pounds, and measures 3.5& cubic feet.
There are obvious concerns about dangers to the public from stepping on an electrified metal strip, and some question the viability of digging up large stretches of road to install the infrastructure. But the idea does have precedents. Boston’s Logan Airport, for example, has ordered 60 “Online Electric Vehicles” that operate under a similar principle, and were developed by the Korea Advanced Institute of Science and Technology.
[Image: Flickr user Mykl Roventine]
New combination of nanoparticles and graphene results in a more durable catalytic material for fuel cells
Bracing catalyst in material makes fuel cell component work better and last longer
A nanoparticle of indium tin oxide (green and red) braces platinum nanoparticles (blue) on the surface of graphene (black honeycomb) to make a hardier, more chemically active fuel cell material. A new combination of nanoparticles and graphene results in a more durable catalytic material for fuel cells, according to work published today online at the Journal of the American Chemical Society. The catalytic material is not only hardier but more chemically active as well. The researchers are confident the results will help improve fuel cell design.
“Fuel cells are an important area of energy technology, but cost and durability are big challenges,” said chemist Jun Liu. “The unique structure of this material provides much needed stability, good electrical conductivity and other desired properties.”
Liu and his colleagues at the Department of Energy’s Pacific Northwest National Laboratory, Princeton University in Princeton, N.J., and Washington State University in Pullman, Wash., combined graphene, a one-atom-thick honeycomb of carbon with handy electrical and structural properties, with metal oxide nanoparticles to stabilize a fuel cell catalyst and make it better available to do its job.
“This material has great potential to make fuel cells cheaper and last longer,” said catalytic chemist Yong Wang, who has a joint appointment with PNNL and WSU. “The work may also provide lessons for improving the performance of other carbon-based catalysts for a broad range of industrial applications.”
Muscle Metal Oxide
Fuel cells work by chemically breaking down oxygen and hydrogen gases to create an electrical current, producing water and heat in the process. The centerpiece of the fuel cell is the chemical catalyst — usually a metal such as platinum — sitting on a support that is often made of carbon. A good supporting material spreads the platinum evenly over its surface to maximize the surface area with which it can attack gas molecules. It is also electrically conductive.
Fuel cell developers most commonly use black carbon — think pencil lead — but platinum atoms tend to clump on such carbon. In addition, water can degrade the carbon away. Another support option is metal oxides — think rust — but what metal oxides make up for in stability and catalyst dispersion, they lose in conductivity and ease of synthesis. Other researchers have begun to explore metal oxides in conjunction with carbon materials to get the best of both worlds.
As a carbon support, Liu and his colleagues thought graphene intriguing. The honeycomb lattice of graphene is porous, electrically conductive and affords a lot of room for platinum atoms to work. First, the team crystallized nanoparticles of the metal oxide known as indium tin oxide — or ITO — directly onto specially treated graphene. Then they added platinum nanoparticles to the graphene-ITO and tested the materials.
The team viewed the materials under high-resolution microscopes at EMSL, DOE’s Environmental Molecular Sciences Laboratory on the PNNL campus. The images showed that without ITO, platinum atoms clumped up on the graphene surface. But with ITO, the platinum spread out nicely. Those images also showed catalytic platinum wedged between the nanoparticles and the graphene surface, with the nanoparticles partially sitting on the platinum like a paperweight.
To see how stable this arrangement was, the team performed theoretical calculations of molecular interactions between the graphene, platinum and ITO. This number-crunching on EMSL’s Chinook supercomputer showed that the threesome was more stable than the metal oxide alone on graphene or the catalyst alone on graphene.
But stability makes no difference if the catalyst doesn’t work. In tests for how well the materials break down oxygen as they would in a fuel cell, the triple-threat packed about 40% more of a wallop than the catalyst alone on graphene or the catalyst alone on other carbon-based supports such as activated carbon.
Last, the team tested how well the new material stands up to repeated usage by artificially aging it. After aging, the tripartite material proved to be three times as durable as the lone catalyst on graphene and twice as durable as on commonly used activated carbon. Corrosion tests revealed that the triple threat was more resistant than the other materials tested as well.
The team is now incorporating the platinum-ITO-graphene material into experimental fuel cells to determine how well it works under real world conditions and how long it lasts.
Reference: Rong Kou, Yuyan Shao, Donghai Mei, Zimin Nie, Donghai Wang, Chongmin Wang, Vilayanur V Viswanathan, Sehkyu Park, Ilhan A. Aksay, Yuehe Lin, Yong Wang, Jun Liu, Stabilization of Electrocatalytic Metal Nanoparticles at Metal-Metal Oxide-Graphene Triple Junction Points, February 8, 2011, J. Am. Chem. Soc., DOI 10.1021/ja107719 (http://pubs.acs.org/doi/full/10.1021/ja107719u.
This work was supported by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy.
Wireless Electricity Transmission Being Deployed to Power Korean Mass Transit
by Michael Keller
Korean trams and buses are moving away from overhead power wires and high-voltage third rails—literally.
Researchers at the Korea Advanced Institute of Science and Technology (KAIST) have made major advances in wireless power transfer for mass transit systems. The fruits of their labor, systems called On-line Electric Vehicles (OLEV), are already being road tested around Korea.
At it’s heart, the technology uses inductive coupling to wirelessly transmit electricity from power cables embedded in roadways to pick-up coils installed under the floor of electric vehicles.
High-performance capacitor could lead to better rechargeable batteries
By Lisa Zyga @ physorg.com
Zeolite-templated carbon is a promising candidate as an electrode material for constructing an electric double layer capacitor with both high-power and high-energy densities, due to its three-dimensionally arrayed and mutually connected 1.2-nm nanopores. This carbon exhibits both very high gravimetric (140−190 F g−1) and volumetric (75−83 F cm−3) capacitances in an organic electrolyte solution. Moreover, such a high capacitance can be well retained even at a very high current up to 20 A g−1. This extraordinary high performance is attributed to the unique pore structure.
The unique 3D array of nanopores in zeolite-templated carbon enables it to be used as an electrode for high-performance supercapacitors that have a high capacitance and quick charge time. Image credit: Hiroyuki Itoi, et al. ©2011 American Chemical Society.
In order to develop next-generation electric vehicles, solar energy systems, and other clean energy technologies, researchers need an efficient way to store the energy. One of the key energy storage devices for these applications and others is a supercapacitor, also called an electric double-layer capacitor. In a recent study, scientists have investigated the possibility of using a material called zeolite-templated carbon for the electrode in this type of capacitor, and found that the material’s unique pore structure greatly improves the capacitor’s overall performance.
To store energy, the electric double-layer capacitor is charged by ions that migrate from a bulk solution to an electrode, where they are adsorbed. Before reaching the electrode’s surface, the ions have to travel through narrow nanopores as quickly and efficiently as possible. Basically, the quicker the ions can travel down these paths, the quicker the capacitor can be charged, resulting in a high rate performance. Also, the greater the adsorbed ion density in the electrode, the greater the charge that the capacitor can store, resulting in a high volumetric capacitance.
Recently, scientists have been testing materials with pores of various sizes and structures to try to achieve both quick ion transport and high adsorption ion density. But the two requirements are somewhat contradictory, since ions can travel more quickly through larger nanopores, but large nanopores make the electrode density low and thus decrease the adsorbed ion density.
The zeolite-templated carbon consists of nanopores that are 1.2 nm in diameter (smaller than most electrode materials) and that have a very ordered structure (whereas other pores can be disordered and random). The nanopores’ small size makes the adsorbed ion density high, while the ordered structure – described as a diamond-like framework – allows the ions to quickly pass through the nanopores. In a previous study, the researchers showed that zeolite-templated carbon with nanopores smaller than 1.2 nm cannot enable fast ion transport, suggesting that this size may provide the optimal balance between high rate performance and high volumetric capacitance.
In tests, the zeolite-templated carbon’s properties exceeded those of other materials, demonstrating its potential to be used as an electrode for high-performance electric double-layer capacitors.
More information: Hiroyuki Itoi, et al. “Three-Dimensionally Arrayed and Mutually Connected 1.2-nm Nanopores for High-Performance Electric Double Layer Capacitor.” Journal of the American Chemical Society. DOI:10.1021/ja108315p
Nissan Aims To Be World Leader In Green Vehicles
TOKYO — Nissan Motor Co. is aiming to be the world’s No. 1 in green cars, targeting cumulative sales of 1.5 million zero-emission vehicles by 2017 with alliance partner Renault SA of France.
The Japanese maker of the Leaf electric car announced Monday its six-year strategy, planning a plug-in hybrid by the fiscal year ending March 2017 and reducing carbon dioxide emissions by 20 percent per vehicle compared with 2005 levels.
Nissan, based in Yokohama, also aims to improve fuel efficiency of its vehicles by 35 percent compared with 2005.
Nissan President and Chief Executive Carlos Ghosn said being ecological can deliver a competitive edge by allowing the automaker to stand out as good corporate citizen.
“More consumers are demanding products in line with their values, including cars and trucks with a lower carbon footprint,” he told reporters at company headquarters. “At the same time, we are using technology to make our factories greener and more efficient.”
Ghosn said Nissan was working on a fuel cell, another kind of zero-emissions vehicle, as well as other types of environmental technology such as clean diesels.
He said growth was coming from emerging markets, and Brazil, India and Russia are expected to overtake Japan in auto demand. The Japanese auto market, which has been stagnant for years, now trails China, the world’s largest.
Japanese automakers suffered a major setback from the March 11 earthquake and tsunami that disrupted suppliers and stalled production for months. Nissan has sprung back relatively well, partly on the back of the boost from emerging markets.
Electric cars remain a niche market so far. Nissan has sold about 16,600 Leaf cars around the world since they went on sale in December 2010.
But competition in electric vehicles is likely to intensify as others, such as Japanese rival Toyota Motor Corp., enter the sector.
Toyota already offers plug-in hybrid cars, which run partly as EVs but switch to become regular hybrids with gas engines when they run out of the electric charge.