Zinc-Ion Battery Could Challenge
➙A long-lasting zinc-ion battery costing half the price of a current lithium-ion battery was developed by chemists at
the University of Waterloo.
Professor Linda Nazar and her colleagues from the Faculty of
Science at Waterloo made the key discovery and hope to use their
findings to help communities veer away from traditional power
plants and gravitate toward renewable energy sources in solar and
“The worldwide demand for sustainable energy has triggered a
New Solar Cell More Efficient
search for a reliable, low-cost way to store it,” says Nazar, a Canada
Research Chair in Solid State Energy Materials and a University
Research Professor in the Department of Chemistry. “The aqueous
zinc-ion battery we’ve developed is ideal for this type of applica-
tion because it’s relatively inexpensive and it’s inherently safe.”
The battery produces electricity through a reversible pro-
cess called intercalation, where positively charged zinc ions are
oxidized from the zinc metal negative electrode, travel through
the electrolyte and insert between the layers of vanadium oxide
nanosheets in the positive electrode. This steers the flow of elec-
trons in the external circuit, creating an electrical current. The
reverse process occurs on charge.
➙Researchers from MIT and the Masdar Institute of Sci- ence and Technology have developed a solar cell that has
potential to be more affordable and efficient than current
photovoltaic cells. The team’s report states that the cell combines
two different layers of sunlight-absorbing material to harvest a
broader range of the sun's energy.
The concept, dubbed “step cell,” consists of t wo layers arranged
in a stepwise fashion, with the lower layer protruding out beneath
the upper layer in order to expose both layers to incoming sunlight.
Layered solar cells such as these are typically expensive to
manufacture, but researchers successfully implemented a low-cost
manufacturing process for this particular cell.
In addition to being cheaper to produce, the PV cell concept is
also much more productive. The team estimates theoretical efficiencies above 40% and approximate practical efficiencies of 35%.
MIT’s Eugene Fitzgerald estimates the step cells could be ready
for the PV market within the next couple of years and plans on
forming a startup company to commercialize it. B
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Cheap Wind Energy Prices Drive
➙Wind energy is pow- ering more American
ever before. With increased
wind energy prices have fallen
and continue to be attractive
to commercial and utility
owners, according to a report
released by the U. S. Depart-
ment of Energy alongside the
Electricity Markets & Policy
Group at Lawrence Berkeley National Laboratory (Berkeley Lab).
“Wind energy prices – particularly in the central United
States – are at rock-bottom levels, with utilities and corporate
buyers selecting wind as the low-cost option,” says Berkeley Lab
Senior Scientist Ryan Wiser. “Moreover, enabled by technology
advancements, wind projects are economically viable in a grow-
Prices for newly built wind projects are averaging around 2
cents/k Wh, a decrease from the 7 cents/k Wh rate in 2009. Wind
turbine prices have fallen 20-40% in the last eight years, result-
ing in significantly decreased installation costs.
Low expenses have stimulated demand for wind energy,
particularly from traditional electric utilities and non-utility
purchasers like corporations, universities and municipalities.
WIND ENERGY PRICES have fallen
significantly, making wind projects
more attractive to building owners.