Post on 03-Jun-2018
transcript
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 1/8
1
NANOTECHNOLOGY
FOR ENERGY APPLICATIONS
NANO CONNECT SCANDINAVIA www.nano-connect.org
Chalmers University of Technology | DTU | Halmstad University | ImegoLund University | University of Copenhagen | University of Gothenburg
ENERGY EFFICIENCY
ENERGY PRODUCTION & POWER TRANSMISSION
ENERGY STORAGE & CONVERSION
Sol Voltaics AB aims to produce portable, semi-conductornanowire-based solar cells using a high volume production
method based on guided self-assembly of nanowires in the
gas phase. Image: Damir Asoli.
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 2/8
2
Thematic Area ”Nano for Energy”
Why nanotechnology matters
The world’s hunger for energy is rapidly increasing while
we at the same time face critical environmental issues as
well as dwindling resources. To manage this situation we
need to produce, transport, store and consume energy in
new and more efcient ways.
Nanotechnology promises to be the tool we need. Design-ing and developing new material properties on the na-
noscale enables new applications and solutions. We are in
fact already seeing products such as energy-efcient LED
lights, new nanomaterials for thermal insulation, low fric-
tion nanolubricants and lightweight nanocomposites on
the market. This is just the beginning.
Many exciting opportunities with huge market potential
will emerge in the decades to come. Nanotechnologies will
affect the entire eld of energy from usage to supply, con-
version and storage. Today the main focus is very much onimproving energy efciency.
With this brochure, Nano Connect Scandinavia, an EU-
nanced project representing seven universities and insti-
tutes in south-western Scandinavia, presents a few prom-
ising areas within the energy eld where nanotechnology
will have a major impact.
WHAT IS NANOTECHNOLOGY?
Nanotechnology is the understanding
and control of matter and processes
at the nanoscale, typically, but not ex-
clusively, below 100 nanometres in one
or more dimensions where the onset
of size-dependent phenomena usually
enables novel applications. Nanotech-
nology is cross-disciplinary in nature,drawing on medicine, chemistry, biol-
ogy, physics and materials science.
New properties
Modied at the nanoscale, matter be-
gins to demonstrate entirely new prop-
erties, also on a macroscopic scale. It
can become stronger, lighter, have im-
proved viscosity, increased stability or
better thermal and electrical properties.
Creating nanostructures
With a bottom-up approach, nano-
structures are formed molecule by mol-
ecule, using methods such as chemical
vapour deposition or self-assembly. By
contrast, top-down fabrication can be
likened to sculpting from a base mate-
rial, and typically involves steps such as
deposition of thin lms, patterning, and
etching
This composite image shows Earth as
seen from space at night. It illustrates
how unevenly energy use is distributed
across the globe, and it gives a taste
of how much mankind’s energy con-
sumption will rise when the “dark” ar-
eas develop. Photo courtesy of NASA.
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 3/8
3
The Volkswagen 1-litre concept car travels 100 km on
one litre of diesel fuel. This extraordinarily high fuel
efciency is possible thanks to lightweight materials,
carefully designed aerodynamics and an engine con-trol system tuned for economy. Photograph by Rudolf
Simon via Wikimedia Commons.
LIGHTWEIGHT CONSTRUCTIONS BOOSTFUEL EFFICIENCY
Nanostructured metal or polymer matrix composites
dene new standards in lightweight design; they offerhigher strength-to-weight ratio, higher resistance against
fatigue and better formability than conventional com-
posite materials owing to the large interfacial area be-
tween matrix and reinforcement structure. They also
display interesting optical, electrical, thermal and mag-
netic properties. Lighter and smaller heat exchange
systems can be constructed by using nanouids, a new
class of heat transfer uids, where the addition of a very
small quantity (<1 % by volume) of nanoparticles to a
traditional heat transfer uid dramatically improves its
thermal properties while not signicantly affecting the
ow properties.
Energy efciencyThe International Energy Agency (IEA) estimates that energy sav -
ings corresponding to almost one fth of the current worldwide en-
ergy consumption can be achieved by improved energy efciency.Nanotechnology enables large energy and cost savings, especially
in the building, transportation and manufacturing industries.
SMART WINDOWS RECONCILE ENERGY EFFICIENCY
AND AESTHETICS
Windows create a connection to the outside world and add natu-
ral light to a building, but they also critically affect the building’s
energy balance. Nanotechnology-based smart windows change
their colour at the ick of a switch – a small applied voltage
changes the appearance of electrochromic glass from transpar-
ent to translucent (and vice versa) as lithium ions and associated
electrons migrate from the counter electrode to an electrochro-
mic electrode layer. Due to efcient heat and light management,
the need for cooling and lighting can thereby be optimally bal-
anced, and motorised shades can be partially eliminated.
AEROGELS RE-DEFINE THERMAL INSULATION
Aerogels are solid nanoporous substances with exceptionally
low density (as low as 3 kg/m3 ) and remarkable thermal insula-
tion properties (thermal conductivities down to 0.004 Wm-1K-1, i.e.
about 8–10 times lower than mineral wool). They are mechani-cally stable, translucent, non-toxic, and non-ammable. While tra-
ditionally expensive, Svenska Aerogel AB has developed a new
production method that enables the material to be produced in
a cost-effective way. Flexible aerogel blankets are available from
Aspen Aerogels.
Excellent thermal insulation can be achieved
with aerogels as illustrated by a ower not
being burnt by a Bunsen burner. Image
courtesy of NASA/Wikimedia Commons.
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 4/8
4
Thematic Area ”Nano for Energy”
Energy production and
power transmission
Nanotechnology is a key enabling technology both to exploit traditionalenergy sources in a more efcient, safe and environmentally friendly
manner, and to tap into the full potential of sustainable energy sources
such as biomass, wind, geothermal and solar power. It also offers so-
lutions to reduce energy losses in power transmission, and to manage
complex power grids with dynamically changing loads and decentral-
ised feed-in stations.
BRIGHT PERSPECTIVES FOR SOLAR ENERGY
The conversion efciency of photovoltaic and photochemical solar cells
is traditionally governed by a compromise – in order to absorb enough
light, at least micrometre-thick layers are required, while charge car-
rier collection is more efcient the thinner the active layer is. Several
types of nanomaterials that absorb light very efciently are currently
under development; they include quantum dots, plasmonically active
metallic nanoparticles and nanowires. Charge carrier collection can be
improved by designing nanostructures which exhibit short collection
paths with reduced recombination losses. Consequently, less active
material is needed and purity requirements can be relaxed. Graphene is
a promising alternative to indium tin oxide, a scarce material commonly
used to fabricate transparent electrodes in solar cells and LCD displays.
Nanotechnology-enabled solar cells can thus be produced at a lowercost and in a more resource-efcient way. Since they can be made ex-
ible, integrating them into buildings is possible.
TURNING WASTE HEAT INTO VALUABLE ELECTRICITY
Thermoelectic materials convert heat directly into electricity (and vice
versa) and can thus recycle some of the energy contained in, for in-
stance, hot exhaust streams. While low efciency has traditionally lim-
ited the use of thermoelectrics to niche markets, recently developed
nanostructured thermoelectrics, with much better performance than
bulk thermoelectrics, mark the beginning of a new era. Progress has
also been made towards inexpensive, large-scale production methods.
Beyond transport and industrial production, interesting application ar-
eas include the transformation of low-grade solar thermal or geothermal
energy, or the use of human body heat to power portable electronics.
BOOSTING POWER GENERATION FROM WIND
The energy provided by a wind turbine is proportional to the square of
the blade length. Nanocomposite materials with excellent strength-to-
weight and stiffness-to-weight ratios enable the construction of longer,
more robust blades. Low-friction coatings and nanolubricants provide
means to reduce energy losses in gearboxes and thus further increase
efciency.
Thermoelectric materials generate a current when
placed in a temperature gradient as a consequence
of charge carrier diffusion from the hot to the cold
side, thus allowing the regeneration of waste heat
into electricity. Reproduced with permission from
NPG Asia Mater. 2, 152–158 (2010) © 2010 Tokyo
Institute of Technology.
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 5/8
5
POWERING PERSONAL ELECTRONICS WITH
YOUR OWN BODY
A nanogenerator is a device, which harvests external me-
chanical energy and converts it into electricity as a result
of bending or stretching nanostructured piezoelectric ma-terials such as zinc oxide nanowires. The mechanical en-
ergy may be provided in a countless number of ways, e.g.
virtually any body movement, a rolling tire, vibrations, or
airow. Nanogenerators capable of powering commercial
liquid-crystal displays or light-emitting diodes have been
demonstrated. Further development will result in devices
powerful enough to drive portable electronics such as a
cell phone, or to extract electricity from wind or waves on
a large scale.
LOST IN TRANSMISSION
A grid capable of massive power transmission across
continental distances with negligible energy losses is a
critical component for a sustainable energy future. Current
copper-based grids leak electricity at about 5% per 100
miles of transmission. A special type of carbon nanotubes,
so-called armchair nanotubes, which exhibit extraordi-
narily low electrical resistance (more than 10 times better
conductivity than copper) and tremendous specic tensile
strength, could revolutionise electricity transmission. The
insulation system accounts for up to 7% of the energy lossduring transmission. Dielectrics based on polymer nano-
composites (nanodielectrics) have shown advantageous
insulating properties, including enhancement of the dielec-
tric breakdown strength and improved erosion and track-
ing resistance, making them interesting candidates for high
voltage outdoor insulation applications.
Nanowires made of piezo-
electric materials can create
electricity from mechanical
motion such as a human
walking or running.
Reproduced with permission from Science
316, 102-105 (2007) Copyright © 2007 American
Association for the Advancement of Science.
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 6/8
6
Thematic Area ”Nano for Energy”
Energy storage & conversionMany sustainable energy sources like wind and solar power deliver signicant power only part of the
time. Strategies to store energy are therefore needed. While the particularly stringent requirements
posed by the transport sector are currently only met by fossil fuels, nanotechnology will make novel
types of energy stores, including electrical stores such as batteries and chemical stores such as hydro-
gen, more competitive.
This fuel cell hybrid vehicle (FCHV) bus
is powered by fuel cells, which generate
electricity from hydrogen, and a nickel-
metal hydride battery in synergy. Photo-
graph by Gnsin via Wikimedia Commons.
PUTTING PRESSURE ON HYDROGEN STORAGE
Hydrogen has a very high energy density by weight, but its low energy density by volume turns its
storage into a major challenge. Nanocomposite materials with exceptional strength-to-weight ratio
can be used to construct lightweight storage tanks with pressure ratings that exceed the perfor-
mance of traditional materials. High surface area materials such as carbon aerogels, carbon na-
nobres or graphene constitute another nanotechnology-based storage option. Current research
focuses largely on chemical methods, where hydrogen reversibly reacts with a solid-state material
such as magnesium. Reducing the dimensions of the storage medium to nanoscale dimensions
can alleviate traditional performance barriers of chemical stores, such as high release temperatures
and slow charge/discharge rates.
Scientists at the Lawrence Berkeley National
Laboratory have recently developed a new,
air-stable nanocomposite material for hy-
drogen storage, where magnesium nanopar-
ticles are embedded in a plastic matrix thatprotects the magnesium from oxidation. The
nanocomposite rapidly absorbs and releases
hydrogen at modest temperatures.
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 7/8
7
JUICE UP YOUR MOBILE PHONE IN SECONDS
The use of nanostructured electrodes in batteries has several advantages. The rate of charge/discharge
is improved, down to a few seconds or minutes depending on storage capacity, thanks to a short ion
transport path, and the energy storage capacity benets from the large surface area. Nanostructured
electrodes are also more robust towards volume changes associated with the intercalation and de-intercalation of ions than bulk electrodes, thereby improving cycle life. These nano-approaches are
compatible with a range of battery chemistries, including lithium-ion and nickel-metal hydride batteries.
SQUEEZING THE MOST OUT OF CATALYSTS
Since the chemical reactions involved occur on the cata-
lyst surface, a catalyst is used more effectively the larger
its specic surface area. Nanoscale catalysts thereforehave a decisive advantage over catalysts made from larg-
er particles, particularly if they are made from expensive
noble metals. Nanotechnology allows the synthesis of the
catalyst particles to be steered in such a way that those
crystal facets with the highest activity grow preferential-
ly at the particle surface, and with the catalyst particles
being uniformly distributed on their support. Processes
like the electrolytic production of hydrogen from water or
the conversion of hydrogen to electricity in a fuel cell can
consequently be run more economically and with more
efcient use of resources. Commercial catalysts for the
aforementioned reactions are developed by Quantum-
Sphere Inc. and 3M respectively.
Pt nanowires grown on carbon nanospheres
show a 50% higher mass activity for the ox-
ygen reduction reaction than a commercial-
ly available fuel cell cathode. Reproduced
with permission from Adv. Mat. 20, 3900-
3904 (2008) © 2008 John Wiley and Sons.
Would you like to know more?
This brochure is part of a series, covering different application areas of nanotechnology, including life
science, materials, electronics & sensors, and the regulatory framework for nanomaterials. Please visit
www.nano-connect.org for more information.
This work was supported by the EU through its Interreg IVA Programme. It reects only the author’s views. The Community
is not liable for any use that may be made of the information contained therein.
Simulated quasispherical amorphous carbon
used as the anode material for intercalation in
lithium ion energy storage. Image courtesy of
Argonne National
Laboratory /ickr
8/12/2019 Nanotechnology for Energy Applications
http://slidepdf.com/reader/full/nanotechnology-for-energy-applications 8/8
8
Thematic Area ”Nano for Energy”
Chalmers University of Technology
Halmstad University
Imego
Lund University
Technical University of Denmark
University of Copenhagen
University of Gothenburg
Halland Regional Development Council
Region Skåne
Region Västra Götaland
Region Zealand
The Capital Region of Denmark
Nano Connect Scandinaviawww.nano-connect.org
Download this and other brochures from:
www.nano-connect.org/downloads
Connecting people who
think bigabout very
smallthings