Nanotechnology
for

Green Building

Green Technology Forum 2007


Nanotechnology for Green
Building
© 2007 Dr. George Elvin
Green Technology Forum


Table of Contents
Executive Summary
Part 1: Nanotechnology and Green Building
1. Introduction
1.1
1.2
1.3

Green Building
Nanotechnology
Convergence

Part 2: Materials
2. Insulation
2.1
2.2
2.3

2.4
2.5

Aerogel
Thin-film insulation
Insulating coatings
Emerging insulation technologies
Future market for nano-insulation

3. Coatings
3.1
3.2
3.3
3.4
3.5
3.6
3.7
3.8
3.9

Self-cleaning coatings
Anti-stain coatings
Depolluting surfaces
Scratch-resistant coatings
Anti-fogging and anti-icing coatings
Antimicrobial coatings
UV protection
Anti-corrosion coatings
Moisture resistance


4. Adhesives
5. Lighting
5.1
5.2
5.3
5.4

Light-emitting diodes (LEDs)
Organic light-emitting diodes (OLEDs)
Quantum dot lighting
Future market for lighting


6. Solar energy
6.1
6.2
6.3

Silicon solar enhancement
Thin-film solar nanotechnologies
Emerging solar nanotechnologies

7. Energy storage
8. Air purification
9. Water purification
10. Structural materials
10.1
10.2
10.3
10.4


Concrete
Steel
Wood
New structural materials

11. Non-structural materials
11.1
11.2
11.3
11.4

Glass
Plastics and polymers
Drywall
Roofing

Part 3: Conclusions
12. Additional benefits
12.1
12.2
12.3
12.4

Nanosensors and smart environments
Multifunctional properties
Reduced processing energy
Adaptability to existing buildings

13. Market forces

13.1
13.2

Forces accelerating adoption
Obstacles to adoption

14. Future trends and needs
14.1
14.2
14.3
14.4
14.5

Independent testing
Life cycle analysis
Societal concerns
Environmental and human health concerns
Regulation

References and links


cover: flexible solar panel from konarka
acknowledgements: an initial study of energy-efficient nanomaterials was made possible by a
fellowship at the center for energy research, education and service


Nanotechnology for Green Building

© 2007 Dr. George Elvin


Executive summary
This report offers a comprehensive research review of current and near future
applications of nanotechnology for green building. Its results suggest that the potential
for energy conservation and reduced waste, toxicity, non-renewable resource
consumption, and carbon emissions through the architectural applications of
nanotechnology is significant. These environmental performance improvements will
be led by current improvements in insulation, coatings, air and water purification,
followed by forthcoming advances in solar and lighting technology, and more distant
(>10 years) potential in structural components and adhesives. U.S. demand for nanoenhanced building materials totaled less than $20 million in 2006, but the market is
expected to reach almost $400 million by 2016. Green building, meanwhile, accounts
for $12 billion of the $142 billion U.S. construction market.1 The convergence of
green building and nanotechnology will result in economic opportunities for both
industries and, most importantly, significant improvements in human and
environmental health.
Based on our research, we divide the timeline for nano-enhanced building materials
into three phases. First, current architectural market applications of nanotechnology
are led by nanocoatings for insulating, self-cleaning, UV protection, corrosion
resistance, and waterproofing. Many of these coatings incorporate titanium dioxide
nanoparticles to make surfaces not only self-cleaning but also depolluting, able to
remove pollutants from the surrounding atmosphere. Insulating nanocoatings promise
significant energy savings, particularly for existing buildings which can be difficult to
insulate with conventional materials. Already gaining market share rapidly in
industrial applications, insulating nanocoatings will soon have a major impact in
architecture.
Coming soon are nanotechnologies for solar energy, lighting, and water and air
filtration. Nano-enhanced solar cell technologies such as organic thin-film and roll-toroll processing are also well under development and will gain an increasing share of
the solar cell market in coming years. Not far behind is nano-enhanced lighting such
as organic light-emitting diodes (OLEDs) and quantum dot lighting. Market
applications of these technologies have already begun with small consumer devices

like cellphone screens, are beginning to enter the architectural lighting market, and
will gain an increasing percentage of that market in the future due to their energysaving capabilities. Nanotechnologies for water and air filtration, already widely
available as consumer products, will gain an increasing percentage of the market for
built-in filtration systems.
In the future, advances in fire protection through nanotechnology suggest great
opportunity as extensive research in this area moves from the universities and research
centers into commercial production. Extensive research underway on nanoenhancement of structural materials including steel, concrete and wood suggests that

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dramatic improvements are possible in this area, although their marketplace
applications are, in most cases, many years off.
Public and building industry reaction to nanotechnology has been largely positive so
far. Nanomaterials have already been used in hundreds of buildings, including highend projects like the Jubilee Church in Rome by Richard Meier and Partners and New
York’s Bond Street Apartment Building by Herzog & de Meuron. We have even
incorporated several nanocoatings into our office construction at Green Technology
Forum with positive results.
However, a number of factors stand in the way of widespread adoption. Current
obstacles to the adoption of nanotechnology for green building include the high cost of
many nanotech products and processes, risk aversion and the traditional hesitancy of
the building industry to embrace new technologies, as well as uncertainty about the
health and environmental effects of nanoparticles and public acceptance of
nanotechnology. Lack of independent testing and the current reliance on manufacturer
claims in determining the architectural and environmental performance of most nanoproducts could also hinder adoption.
But as this report reveals, many nano-enhanced products are available today which

offer substantial architectural and environmental performance improvements over
conventional products. Many coatings, for example, can protect building surfaces and
reduce the need for harsh chemical cleansers while producing no volatile organic
compounds (VOCs) and even removing pollutants from their surroundings. If
consumers embrace nanotechnology as a green technology, if building owners,
architects, contractors and engineers accept uncertainty and risk and embrace
innovation, and if the high cost of nano-products continues to fall, the tremendous
promise of nanotechnology for green building will be realized.
As prices for nano-enhanced building products continue to fall, as buyers weigh their
life cycle and environmental cost advantages, and building industry leaders become
more familiar with nanotechnology, its widespread adoption seems inevitable.
Nanotechnology for green building will reduce waste and toxicity, as well as energy
and raw material consumption in the building industry, resulting in cleaner, healthier
buildings. In addition to the human health and environmental benefits nanotechnology
for green building is poised to make, economic benefits for both the building industry
and nanomaterials industry appear considerable. The demand for green building is at a
an all-time high, and building owners, architects, contractors and engineers adopting
nanotechnology for green building are likely to emerge as leaders and be rewarded
accordingly for their services. For nanotechnology companies, green building
represents one of the largest markets possible for new products and processes.
The Green Technology Forum report on nanotechnology for green building identifies
130 startups and established companies offering or developing nanomaterials for green
building, 54 projects underway at universities and research centers, 43 recent patents
available for licensing, and over 250 citations and links to these resources.

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Part 1. Nanotechnology and Green Building
1. Introduction
The design, construction and operation of buildings is a $1 trillion per year market as
yet largely untouched by nanotechnology. Demand for nanomaterials in the U.S.
construction industry in 2006 totaled less than $20 million.2 However, as this report
shows, the migration of the entire building industry toward more sustainable “green”
practices is a multi-billion dollar opportunity for the makers and suppliers of
nanotech-based materials and products. For architects, engineers, developers,
contractors and building owners, new nanomaterials and nano-products offer
extraordinary environmental benefits to help meet the rapidly growing demand for
greener, more sustainable buildings.
Nanotechnology, the manipulation of matter at the molecular scale, is bringing new
materials and new possibilities to industries as diverse as electronics, medicine, energy
and aeronautics. Our ability to design new materials from the bottom up is impacting
the building industry as well. New materials and products based on nanotechnology
can be found in building insulation, coatings, and solar technologies. Work now
underway in nanotech labs will soon result in new products for lighting, structures,
and energy.
In the building industry, nanotechnology has already brought to market self-cleaning
windows, smog-eating concrete, and many other advances. But these advances and
currently available products are minor compared to those incubating in the world’s
nanotech labs today. There, work is underway on illuminating walls that change color
with the flip of a switch, nanocomposites as thin as glass yet capable of supporting
entire buildings, and photosynthetic surfaces making any building faỗade a source of
free energy. By 2016, the market for nanomaterials in U.S. construction is expected to
reach almost $400 million, twenty times its current volume.3

1.1 Green building

The advent of the nano era in building could not have come at a better time, as the
building industry moves aggressively toward sustainability. Green building is one of
the most urgent environmental issues of our time. The energy services required by
residential, commercial, and industrial buildings are responsible for approximately 43
percent of U.S. carbon dioxide emissions. Worldwide, buildings consume between 30
and 40 percent of the world’s electricity.4 Waste from building construction accounts
for 40 percent of all landfill material in the U.S., and sick building syndrome costs an

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estimated $60 billion in healthcare costs annually. Deforestation, soil erosion,
environmental pollution, acidification, ozone depletion, fossil fuel depletion, global
climate change, and human health risks are all attributable in some measure to
building construction and operation. Clearly, buildings play a leading role in our
current environmental predicament.

percentage of annual impact (us)
energy use 42%
atmospheric emissions 40%
raw materials use 30%
solid waste 25%
water use 25%
water effluents 20%
0%


50%

100%

Environmental impact of buildings
Buildings figure prominently in world energy consumption, carbon
emissions, and waste. (Source: Levin, “Systematic Evaluation and
Assessment of Building Environmental Performance (SEABEP),”
Buildings and Environment, Paris, June 9-12, 1997)

But they also offer a vast opportunity to improve environmental quality and human
health. Green building is a catch-all phrase encompassing efforts to reduce waste,
toxicity, and energy and resource consumption in buildings. The green building
movement has grown to the point that major cities like Chicago and Seattle now
require new buildings to comply with strict environmental standards. More and more
public and private owners are requiring that new construction meet stringent
sustainability benchmarks like the U.S. Green Building Council’s Leadership in
Energy and Environmental Design (LEED) criteria. The Council of American
Building Officials' Model Energy Code (residential) and ASHRAE Standard 90.1
(commercial) propose tougher energy saving requirements, and the proposed EU
Directive on the Energy Performance of Buildings also sets minimum energy
performance standards for new buildings.
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In 2007, the green building sector of the $142 billion U.S. construction market is

expected to exceed $12 billion.5 And as owners, architects and builders worldwide
become increasingly committed to green building, a true paradigm shift is emerging,
from buildings as one of the primary causes of environmental damage and global
climate change to the industry with the greatest potential to reduce carbon emissions,
waste, and energy consumption.
Analyses of global climate change and global-scale plans to alleviate it affirm the
importance of building as our primary opportunity to heal the planet. “Tackling
Climate Change in the U.S.,” by the American Solar Energy Society, for example,
suggests that 40 percent of the energy savings required to achieve necessary carbon
reductions could come from the building sector, with transportation and industry
providing about 30 percent each.6 Better building envelope design, daylighting, more
efficient artificial lighting, and better efficiency standards for building components
and appliances are all opportunities to make the building industry the leader in fighting
global climate change and advancing sustainable development and energy
conservation.
Green building practitioners seek to implement sustainable development,
“development that meets the needs of the present without compromising the ability of
future generations to meet their own needs,” in the design, construction and operation
of buildings.7 They strive to minimize the use of non-renewable resources like coal,
petroleum, natural gas and minerals, and minimize waste and pollutants. Energy
conservation is critical to green building because it both conserves resources and
reduces waste and pollutants.
But a number of obstacles stand between green builders and these goals. Education
and economics are certainly factors, and efforts are well underway to inform clients
that initial design and construction costs for green buildings are typically less than 5
percent more than the waste- and energy-intensive buildings of the past, and that life
cycle costs for green buildings are actually lower. Policies, regulations and standards
also play a role, and these are changing quickly in some areas to allow for greener
alternatives like recycled materials and graywater systems.
But for the building industry to achieve its potential as the leader in sustainable

development, new materials are urgently needed. A trip to the lumber yard just a few
years ago to buy materials for a new deck, for example, would turn up the unpleasant
options of arsenic-laden pressure-treated lumber, non-renewable old-growth redwood,
or environmentally toxic vinyl decking. An effort to conserve energy by installing attic
insulation would meet with the alternatives of fiberglass, polystyrene, or cellulose
laced with fire-retardant chemicals, all considered dangerous. Current windows are
extremely poor insulators, leading to increased energy consumption. And alternatives
to polyvinyl chloride (PVC) pipe for plumbing are healthier than this known
carcinogen but scarce and costly. Now, however, a new frontier is opening in building
materials as nanotechnology introduces new products and new possibilities.

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1.2 Nanotechnology
Nanotechnology, the understanding and control of matter at dimensions of roughly
one to one hundred billionths of a meter, is bringing dramatic changes to the materials
and processes of science and industry worldwide. $13 billion worth of products
incorporating nanotechnology were sold last year, with sales expected to top $1 trillion
by 2015.8 In 2004, over $8 billion was spent in the U.S. alone on nanotech research
and development.

Dimensions at the nanoscale
The diameter of a nanoparticle is to the diameter of a soccer ball as the
soccer ball’s diameter is to the Earth’s. (Source: Green Technology
Forum)


By working at the molecular level, nanotechnology opens up new possibilities in
material design. In the nanoscale world where quantum physics rules, objects can
change color, shape, and phase much more easily than at the macroscale. Fundamental
properties like strength, surface-to-mass ratio, conductivity, and elasticity can be
designed in to create dramatically different materials.
Nanoparticles have unique mechanical, electrical, optical and reactive properties
distinct from larger particles. Their study (nanoscience) and manipulation
(nanotechnology) also open up the convergence of synthetic and biological materials

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as we explore biological systems which are configured to the nanoscale. Crossing the
traditional boundaries between living and non-living systems allows for the design of
new materials with the advantages of both, and it raises ethical concerns. Advances in
biomaterials and biocomposites converge with advances in nanotechnology, and an
increase in their application to construction seems certain to emerge in the future.

Carbon nanotubes
Carbon nanotubes can be up to 250 times stronger than steel and 10
times lighter, as well as electrically and thermally conductive. (Source:
Nanomix)

But with new materials and technologies come new concerns. Uncertainty surrounding
the interaction of nanoscale particles with the environment and the human body has

led to caution and concern about toxicology, worker health and safety, and regulation.
Regulations specific to nanomaterials and products have been slow to emerge, partly
due to the inherent difficulty in regulating materials based on particle size, as well as
lack of public outcry in favor of stiffer regulation and the success so far of selfregulation by industry and the avoidance of any nano-disasters.

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1.3 Convergence
“It is not as though nanotechnology will be an option; it is going to be essential for
coming up with sustainable technologies.” advises Paul Anastas, director of the
American Chemical Society Green Chemistry Institute. 9 The nanotech community
appears ready to meet Anatsas’ challenge, and the market for nano-based products and
processes for sustainability is expected to grow from $12 billion in 2006 to $37 billion
by 2015.10 New materials and processes brought about by nanotechnology, for
example, offer tremendous potential for fighting global climate change. According to
the report, “Nanotechnologies for Sustainable Energy,” by Research and Markets,
“Current applications of nanotechnologies will result in a global annual saving of
8,000 tons of carbon dioxide in 2007, rising to over 1 million tons by 2014.”11
Globally, nanotechnologies are expected to reduce carbon emissions in three main
areas: 1) transportation, 2) improved insulation in residential and commercial
buildings, and 3) generation of renewable photovoltaic energy.12 It is worth noting that
the last two of these three areas are centered in the building industry, suggesting that
building could in fact lead the green nano revolution.
Many nano-enhanced products and processes now on the market can help create more
sustainable, energy-conserving buildings, providing materials that reduce waste and

toxic outputs as well as dependence on non-renewable resources. Other products still
in development offer even more promise for dramatically improving the
environmental and energy performance of buildings. Nano-enabled advances for
energy conservation in architecture include new materials like carbon nanotubes and
insulating nanocoatings, as well as new processes including photocatalysis.
Nanomaterials can improve the strength, durability, and versatility of structural and
non-structural materials, reduce material toxicity, and improve building insulation.

chemical 53%
semiconductor 34%
electronics 7%
aero/defense 3%
pharma/health 2%
automotive 1%
food <1%

Nanotechnology markets 2007
Building construction is not yet a significant market for nanotechnology.
(Source: Cientifica, “Nanotechnologies and energy whitepaper,” 2007)

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Rank

Technology


1

Electricity Storage

1

Engine Efficiency

2

Hydrogen Economy

3

Photovoltaics

3

Insulation

4

Thermovoltaics

4

Fuel Cells

4


Lighting

6

Lightweighting

6

Agriculture
Pollution Reduction

7

Drinking Water
Purification

8

Environmental
Sensors

8

Remediation

Ranking of environmentally friendly
nanotechnologies
Most environmentally friendly nanotechnologies are well-suited to use
in buildings (Source: Oakdene Hollins, “Environmentally Beneficial

Nanotechnologies,” 2007)

The chart and table above reveal that building construction is not yet a significant
market for nanotechnology. But that is not necessarily bad news for either the
construction industry or the marketers of nano-products. The construction industry has
long been slow to adopt new technologies, and the nanotech era is proving to be no

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exception. The demands of public and private building owners for greener materials,
demands increasingly being enforced as regulations in many instances, will soon force
architects and engineers to specify greener materials in buildings. This demand,
combined with the environmentally friendly character of most nano-products for
architecture, will create a synergy that we expect will result in a boom in demand for
nanotechnology for green building.

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Part 2. Materials
2. Insulation

The market for green building materials and technologies will of course be determined
more by market pull--the needs of architects, owners and contractors--than by the
technological push of new nanomaterials discovered and developed in the laboratory.
But the convergence of green building demands and green nanotechnology capabilities
over the next 5-10 years appears very strong. It suggests eight categories of
nanotechnology for green building that are the focus of this report.
Insulation
Coatings
Adhesives
Solar energy
Lighting
Air and water filtration
Structural materials
Non-structural materials
The demand from both public and private enterprise for more energy efficient
buildings will lead to significant growth in the insulation sector in the next few years.
Valued at $7.2 billion value in 2005, it is expected to reach $9.5 billion by 2010.13
Current building insulation is estimated to save about 12 quadrillion Btu annually or
42 percent of the energy that would be consumed without it.14 Building insulation
reduces the amount of energy required to maintain a comfortable environment.
Reduced energy consumption, in turn, means reduced carbon emissions from energy
production. Insulation is, in fact, the most cost-effective means of reducing carbon
emissions available today.
Improving on current building insulation could save even more energy and carbon
emissions. EU households, for instance, are responsible for one quarter of EU carbon
emissions, roughly 70 percent of which comes from meeting space heating needs.
Space heating savings through better insulation in Germany, The Netherlands, Italy,
UK, Spain and Ireland, would reduce EU carbon emissions by 100 million metric tons
per year.15 As the table below indicates, improved thermal insulation could meet over
25 percent of EU carbon reduction goals by 2010. In the U.S., improved insulation

could save 2.2 quadrillion Btu of energy (3 percent of total energy use) and reduce
carbon emissions by 294 billion pounds annually.16

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Improvement

CO2 Reduction (tons/yr) by
2010

Thermal
Insulation

174-196

Glazing
Standards

50

Lighting
Efficiency

50


Controls

26

Potential sources of EU CO2 emission reductions
Buildings have the potential to become leading sources of CO2
reductions. (Source: CALEB Management Services, "Assessment of the
potential savings of CO2 emissions in European building stock", May
1998)

Today’s building insulation industry is in many ways a model of large-scale industrial
recycling. Fiberglass insulation manufacturers are the second largest user of postconsumer recycled glass in the U.S., slag wool insulation typically contains 75 percent
recycled content, and most cellulose insulation is approximately 80 percent postconsumer recycled newspaper by weight.17
Health effects of several insulating materials are a concern, however, and improved
health and environmental performance could lead to greater use and therefore energy
conservation. Some sources argue that the fibers released from fiberglass insulation
may be carcinogenic, and fiberglass insulation now requires cancer warning labels.
There are also claims that the fire retardant chemicals or respirable particles in
cellulose insulation may be hazardous. And the styrene used in polystyrene insulation
(often known by the brand name Styrofoam) is identified by the EPA as a possible
carcinogen, mutagen, chronic toxin, and environmental toxin.18, 19 Polystyrene also
poses a resource concern because it is produced from ethylene, a natural gas
component, and benzene, which is derived from petroleum. Two other insulating
materials, polyisocyanurate and polyurethane, are also derived from petroleum.
Nanotechnology promises to make insulation more efficient, less reliant on nonrenewable resources, and less toxic, and it is delivering on many of those promises
today. Manufacturers estimate that insulating materials derived from nanotechnology
are roughly 30 percent more efficient than conventional materials.20
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Nanoscale materials hold great promise as insulators because of their extremely high
surface-to-volume ratio. This gives them the ability to trap still air within a material
layer of minimal thickness (conventional insulating materials like fiberglass and
polystyrene get their high insulating value less from the conductive properties of the
materials themselves than from their ability to trap still air.) Insulating nanomaterials
may be sandwiched between rigid panels, applied as thin films, or painted on as
coatings.

Making nanofibers from cotton waste
While cellulose insulation is made from 80 percent post-consumer
recycled newspaper, the equivalent of 25 million 480-pound cotton
bales are discarded as scrap every year in the garment industry.
"Producing a high-performance material from reclaimed cellulose
material will increase motivation to recycle these materials at all
phases of textile production and remove them from the waste
stream," said Margaret Frey, an assistant professor of textiles and
apparel at Cornell.
Frey and her collaborators are using electrospinning techniques to
produce usable nanofibers from waste cellulose. These nanofibers
could form the basis of new insulating materials from cellulose
which, as the basic building block of all plant life, represents the
most abundant renewable resource on the planet.21

2.1 Aerogel
Aerogel is an ultra-low density solid, a gel in which the liquid component has been
replaced with gas. Nicknamed “frozen smoke”, aerogel has a content of just 5 percent

solid and 95 percent air, and is said to be the lightest weight solid in the world. Despite
its lightness, however, aerogel can support over 2,000 times its own weight.
Because nanoporous aerogels can be sensitive to moisture, they are often marketed
sandwiched between wall panels that repel moisture. Aerogel panels are available with
up to 75 percent translucency, and their high air content means that a 9cm (3.5”) thick
aerogel panel can offer an R-value of R-28, a value previously unheard of in a
translucent panel.22 Architectural applications of aerogel include windows, skylights,
and translucent wall panels.

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Currently, major companies in the aerogel arena include the Cabot Corporation
(makers of Nanogel,) Aspen Aerogels, Kalwall (using Cabot’s Nanogel,) and TAASI
(makers of Prstina aerogels.)
Brown University currently has several aerogel technologies available for licensing,
including one that can be used as a coating to permit printing on materials that
normally cannot be printed on. These aerogels can bind various gases for use as
detectors, and can be colored or ground into very small particles and applied like ink
using a printer. They are also transparent and have a low refractive index, making
them useful as light-weight optical materials.23

Aerogel: the world’s lightest solid
A 9cm (3.5”) thick aerogel panel can offer an R-value of R-28. (Source:
Sandia National Laboratory)


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r-value per inch
0

4

8

12

16

20

24

aspen aerogels spaceloft
polyisocyanurate foam
polystyrene foam
mineral wool
fiberglass batts

Aerogels offer superior insulation
Aerogels offer 2-3 times the insulating value of other common insulating

materials. (Source: Aspen Aerogels)

Nanogel panels provide translucency and
insulation
High-insulating Nanogel panels are available with up to 75 percent
translucency. (Source: Kalwall)

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2.2 Thin-film insulation
Insulating nanocoatings can also be applied as thin films to glass and fabrics. Masa
Shade Curtains, for example, are fiber sheets coated with a nanoscale stainless steel
film. Thanks to stainless steel's ability to absorb infrared rays, these curtains are able
to block out sunlight, lower room temperatures in summer by 2-3º C more than
conventional products, and reduce electrical expenses for air conditioning, according
to manufacturer claims.24
Heat absorbing films can be applied to windows as well. Windows manufactured by
Vanceva incorporate a nanofilm “interlayer” which, according to the company, offers
cost effective control of heat and energy loads in building and solar performance
superior to that of previously available laminating systems. By selectively reducing
the transmittance of solar energy relative to visible light, they say, these solar
performance interlayers result in savings in the capital cost of energy control
equipment as well as operating costs of climate control equipment. Benefits include
the ability to block solar heat and up to 99 percent of UV rays while allowing visible
light to pass through.25


uv blockage
0%

100%
masa shade curtain 84%

untreated curtain 58%

Stainless steel nanofilm improves UV light
blockage
Masa Shade Curtains reduce room temperatures and air conditioning by
improving blockage of ultraviolet (UV) rays. (Source: Suzutora
Corporation)

3M has developed a range of nanotech-based window films that reduce heat and
ultraviolet light penetration. Their films reject up to 97 percent of the sun's infrared
light and up to 99.9 percent of UV rays. Unlike many reflective films, theirs are metalfree and therefore less susceptible to corrosion in coastal environments and less likely
to interfere with mobile phone reception. These films also have less interior
reflectivity than the glass they cover. 26

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Exterior reflectivity can also be controlled by nanofilms. Technology from Rensselaer
Polytechnic Institute and Crystal IS, Inc. has led to highly anti-reflective coatings

utilizing silicon dioxide and titanium dioxide nanorods for a variety of surfaces. Their
coating has a refelctivity index of just 1.05, the lowest ever reported.27
Infrared (IR) rays can also be blocked using transparent IR-absorbing coatings for
heat-absorbing films for windows. VP AdNano ITO IR5, used in transparent film
coatings, improves solar absorption properties while maintaining optical transparency,
according to its manufacturer, Degussa. The use of AdNano ITO on windows, they
claim, improves heat management, greatly reducing the energy consumption of air
conditioners, thereby lowering greenhouse gas emissions. Production of AdNano ITO,
they add, does not pollute the environment with heavy metals, and consumes very
little energy because drying and calcination take place at moderate temperatures.28

2.3 Insulating coatings
Insulation can also be painted or sprayed on in the form of a coating. This is a
tremendous advantage nanocoatings offer over more conventional bulk insulators like
fiberglass, cellulose, and polystyrene boards, which often require the removal of
building envelope components for installation.
Because they trap air at the molecular level, insulating nanocoatings even a few
thousands of an inch thick can have a dramatic effect. Nanoseal is one company
already making insulating paints for buildings. Their insulating coating is also being
used on beer tanks by Corona in Mexico, resulting in a temperature differential of 36
degrees Fahrenheit after application of a coating just seven one thousands of an inch
thick.29
Industrial Nanotechnology, the makers of Nansulate HomeProtect Interior paint,
advertise that the average surface temperature difference when applied correctly is
approximately 30 degrees Fahrenheit for three coats. For Nansulate HomeProtect
ClearCoat, they claim an average surface temperature difference of approximately 60
degrees Fahrenheit. Nansulate PT is being applied to aluminum ceiling panels in the
new Suvanabhumi International Airport in Bangkok, the world’s largest airport.30
HPC HiPerCoat and HiPerCaot Extreme are currently used as thermal barrier coatings
by NASA and NASCAR. Their ceramic-aluminum coating process, they report,

reduces radiant heat and ambient underhood temperature in autos by more than 40
percent. It also offers a corrosion-resistant alternative to environmentally harmful
chrome-plating.31
Industrial Nanotech is even developing thermal insulation that will generate
electricity. The thin sheets of insulation use the temperature differential that insulation
creates as a source for generating electricity. “The fact that there is almost always, day
or night and anywhere in the world, a difference between the temperature inside a
building and outside a building gives us an almost constant source of energy
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generation to tap into,” said CEO Stuart Burchill. The company is now designing the
first prototype material and filing patents.32
NanoPore Thermal Insulation uses silica, titania and carbon in a 3D, highly branched
network of particles 2-20 nanometers in diameter to create a unique pore structure.
According to its maker, NanoPore Thermal Insulation can provide thermal
performance unequalled by conventional insulation materials. In the form of a vacuum
insulation panel, It can have thermal resistance values as high as R-40/inch--7 to 8
times greater than conventional foam insulation materials.
NanoPore’s makers claim that its conductivity can actually be lower than air at the
same pressure. Its superior insulation characteristics, they say, are due to the unique
shape and small size of its large number of pores. Solid phase conduction is low due to
the materials low density and high surface area, and NanoPore’s proprietary blend of
infra-red opacifiers greatly reduces radiant heat transfer.33
Nanoparticles with extreme insulating value can also be incorporated into
conventional paints, as in the case of INSULADD paints. As its manufacturer

describes it, the complex blend of microscopic hollow ceramic spheres that makes up
INSULADD have a vacuum inside like mini-thermos bottles. The ceramic materials
have unique energy savings properties that reflect heat while dissipating it. The hollow
ceramic microspheres in INSULADD create a thermal barrier by refracting, reflecting,
and dissipating heat.34

expanded polystyrene

nanopore

Superior insulation with reduced thickness
330 cm3 of Nanopore insulating nanocoating (right) provides the same Rvalue as 7000 cm3 of polystyrene (left). (Source: Nanopore Incorporated)

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Inside an insulating nanocoating
Nansulate Shield is an insulation material designed specifically for
the construction industry. It is an ultra-thin insulation that,
according to its manufacturer, has an R-Value many times higher
than the current best building insulation available. It is a
nanocomposite insulation composed of 70 percent “Hydro-NMOxide” and 30 percent acrylic resin and performance additive. A
liquid applied coating, the material dries to a thin layer and
provides insulation as well as corrosion and rust protection. The
manufacturers describe their product’s performance this way:
“Thermal conduction through the solid portion is hindered by the

tiny size of the connections between the particles making up the
conduction path, and the solids that are present consist of very
small particles linked in a three-dimensional network (with many
"dead-ends"). Therefore, thermal transfer through the solid portion
occurs through a very complicated maze and is not very effective.
Air and gas in the material can inherently also transport thermal
energy, but the gas molecules within the matrix experience what is
known as the Knudsen effect and the exchange of energy is
virtually eliminated. Conduction is limited because the "tunnels"
are only the size of the mean-free path for molecular collisions,
smaller than a wave of light, and molecules collide with the solid
network as frequently as they collide with each other. The unique
structure... nanometer-sized cells, pores, and particles, means poor
thermal conduction. Radiative conduction is low due to small mass
fractions and large surface areas.”35

Hydro-NM-Oxide ----------- 10 to 13
Polyurethane Foam -------- 6.64
Fiberglass (batts) ----------- 3.2
Cellulose ---------------------- 3.2 to 3.7

R-value comparison of insulation
Similar to aerogel, insulating nanocoatings like
the active ingredient in Nansulate Shield provide
2-3 times the R-value of ordinary insulators
(Source: Industrial Nanotech)

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2.4 Emerging insulation technologies
Work is underway at many universities and research centers to develop new insulating
materials based on nanotechnology. University of California scientists working at Los
Alamos National Laboratory, for instance, have developed a process for modifying
silica aerogels to create a silicon multilayer that enhances the current physical
properties of aerogels. With the addition of a silicon monolayer, they say, an aerogel's
strength can be increased four-fold. This could expand the range of applications for
aerogels, which must currently be protected by surrounding panels.36
At EMPA Research Institute in Switzerland, work is underway to create vacuum
insulated products using plastic films such as PET, polyethylene and polyurethane
treated with an ultra-thin coating of aluminum. Only about 30 nanometers thick, the
aluminum layer significantly reduces the gas permeability of the film while at the
same time barely raising its thermal conductivity. The resulting cladding layer is thin,
homogeneous and gas-tight. The higher cost (still about double that of conventional
materials) is offset by the space-saving potential the new materials offer.37
Many products of current research on nano-insulation are available for licensing. For
example, eight licensable patents for aerospace insulation materials are available
through the Engineering Technology Transfer Center at the USC Viterbi School of
Engineering, including “Composite Flexible Blanket Insulation,” “Durable Advanced
Flexible Reusable Surface Insulation,” and “Flexible Ceramic-Metal Insulation
Composite.” 38
Also available for licensing are NASA’s Ames Research Center’s novel
nanoengineered heat sink materials enabling multi-zone, reconfigurable thermal
control systems in spacesuits, habitats, and mobile systems. This platform technology
can be adapted to a wide range of form factors thanks to a flexible metallic substrate.


2.5 Future market for nano-insulation
If the field performance of nano-insulation products lives up to manufacturer claims,
these products could foster dramatic improvements in energy savings and carbon
reduction. However, independent testing of insulating nanomaterials and products in
use will be necessary to verify manufacturer claims and convince potential buyers of
their effectiveness. Some manufacturers are already making the results of such testing
public, with encouraging results.
One of the greatest potential energy-saving characteristics of nanocoatings and thin
films is their applicability to existing surfaces for improved insulation. They can be
applied directly to the surfaces of existing buildings, whereas the post-construction
addition of conventional insulating materials like cellulose fiber, fiberglass batts, and
rigid polystyrene boards typically require expensive and invasive access to wall
cavities and remodeling. Nanocoatings could also make it much easier to insulate
solid-walled buildings, which make up approximately one third of the UK’s housing

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