Sept_AMP_Digital

14 / 74

news
industry
Nanotubes boost batteries
Researchers at the DOE’s National Re-
newable Energy Laboratory (NREL), Golden,
Colo., are turning to extremely tiny tubes and
rods to boost power and durability in
lithium-ion batteries, the energy source for
cell phones, laptops, and electric vehicles. If
successful, the batteries will last longer and
perform better, leading to a cost advantage
for electric vehicles.
Scientists created crystalline nanotubes
and nanorods to attack the major challenges
inherent in lithium-ion batteries—they can
get too hot, weigh too much, are not great
conductors of electricity, and do not rapidly
charge and discharge. NREL’s most recent
contribution toward much-improved batteries are high performance, binder-free, carbon-
nanotube-based electrodes. The technology has attracted interest from industry and is
being licensed to NanoResearch Inc. for volume production.
Two-bladed wind turbines save materials, costs
Several major wind-power companies are testing a departure from the industry’s stan-
dard three-bladed turbine design by eliminating one of the blades and spinning the rotor
180° to face downwind. By some estimates, two-bladed turbines could cost
20% less to build and install while generating the same amount of power
as conventional turbines.
China’s Ming Yang Wind Power recently announced plans for the largest
test of the new design to date. It will erect a six-megawatt, two-bladed tur-
bine in China this year that will generate as much power as the largest
commercial offshore turbines. Ming Yang plans to build another in Nor-
wegian waters next year.
Two-bladed turbines cost less because they use fewer materials. Remov-
ing one blade also makes the rotor lighter, which in turn makes it possible
to place the rotor on the downwind side of the tower. Conventional rotors
face the wind and must resist bending back into the tower, but downwind
rotors can use lighter and even hinged blades that bend away from heavy
gusts. Light, flexible rotors translate into further materials savings in the
gearbox, tower, and foundation. The 140-m-diameter rotor, gearbox, and generator for
Ming Yang’s prototype weigh just 308 tons—about 40 tons less than those of Siemens’ con-
ventional six-megawatt offshore turbines. .
Generating electricity one drop at a time
Last year, Massachusetts Institute of Technology, Cambridge, researchers dis-
covered that when water droplets spontaneously jump away from superhydropho-
bic surfaces during condensation, they can gain electric charge in the process. Now,
the same team demonstrated that this process can generate small amounts of elec-
tricity that might be used to power electronic devices. The device itself could be
simple, consisting of a series of interleaved flat metal plates, explains researcher
NenadMiljkovic. Although initial tests involved copper plates, he says any conduc-
tive metal would do, including aluminum, which is less expensive. For more infor-
mation: Nenad Miljkovic, 617.981.9247, , .
Experimental chamber as seen from the front, with high-speed camera looking in from
the left. Courtesy of Nenad Miljkovic and Daniel J. Preston.
ADVANCED MATERIALS & PROCESSES • SEPTEMBER 2014 14
ENERGY TRENDS
briefs
The U.S. Department of Energy
(DOE), Washington, will extend
funding totaling $14 million over
four years for an Energy Frontier
Research Center (EFRC) first
established at DOE’s Brookhaven
National Laboratory in 2009.
Dubbed the Center for Emergent
Superconductivity, the EFRC is led
by Brookhaven with partners from
the University of Illinois at
Urbana-Champaign and DOE’s
Argonne National Laboratory,
Chicago, with the aim of
understanding the fundamental
nature of superconductivity in
complex materials—a potentially
transformative property that could
revolutionize energy distribution
and storage. energy.gov, anl.gov,
bnl.gov, .
To help design more sustainable
buildings, Dow Corning Corp.,
Midland, Mich., introduced an air
and water barrier system.
Evaluated by the Air Barrier
Association of America, the Dow
Corning Silicone Air Barrier System
is a suite of compatible high-
performance silicone technologies
designed to work together to better
protect the entire building
envelope and improve energy
efficiency. The system meets NFPA
285 and is NFPA Class A/UBC
Class 1 per ASTM E84. It can be
used on both new construction and
renovation projects, and its low-
VOC formula makes it suitable for
green construction.
.
NREL Scientist Chunmei Ban assembles a
lithium-ion battery in the materials lab at the
Solar Energy Research Facility at NREL.
Courtesy of Dennis Schroeder, NREL.
Two-bladed
wind turbines,
like this one in
China, could
lower the cost of
wind power.