alternative energy industry has turned to bonding and sealing as a way
engineer, design, protect, and fabricate new devices for the production
clean, efficient electrical energy.
Figure 1. Conventional and Popular Alternative Electrical Energy Sources
and alternative energy sources are popular buzzwords in the 21st century, and
they are becoming more familiar to the adhesive and sealant industry as
chemical feedstocks remain in short supply and prices increase. The move is on
to reduce energy costs, become less dependent on fossil fuels and lower our
“carbon footprint.” It is inevitable that adhesive and sealant products develop
a more active participation in this new growth opportunity.
The alternative energy industry has turned to bonding and sealing as a way to
engineer, design, protect, and fabricate many new and exciting devices to
produce clean, efficient electrical energy. This effort has been supported by
new federal government incentives to promote growth in a recessionary economy.
Electrical power generation has been dominated by coal-, gas- or diesel-fueled
steam turbines, as well as water-powered generators, for the past two
centuries. Nuclear fission entered the market in the 1960s but has not been
readily accepted due to its high installed cost and safety concerns. Recent
improvements in technology, engineering and materials have opened the door to
new sources for power. Many are quite promising and are being adopted at an
ever-increasing rate. The two most popular developments are wind and
photovoltaic (solar) power. A list of conventional and popular alternative
electrical energy sources is provided in Figure 1.
Figure 2. Consumable vs. Renewable Energy Resources
energy sector is further divided between consumable and renewable resources.
Presently, consumable resources make up 86% of the electrical energy produced
in the U.S., while only 14% is generated by renewable resources. Water (hydro)
power is a big portion of the renewable resources segment, followed by wind,
solar (photovoltaic) and others (see Figure 2). Electrical energy produced by
wind turbines is ahead of the other alternatives in terms of both cost and
A more detailed share of the 2009 energy market by generation method is
provided in Figure 3. Many options are available. The final deciding factors
for new investment will be a combination of both the construction cost and the
cost/kW of power produced. See Figure 4 for a comparison.
Figure 3. Energy Market by Generation Method (2009)
sealants and coatings are playing an important role in the growth of wind
turbines, which represents the largest consumer of formulated chemical products
in the sector. The manufacture of wind turbines requires large blades; some are
nearly 60 m (183 ft) long, with a total swing diameter of 120 m (366 ft). These
blades are fabricated in two halves from resin and fabric laminations. When
molded, the half-shells are bonded and each blade can consume up to 450 kg of
epoxy or methyl methacrylate (MMA) adhesive and weigh as much as 15-20 tons.
This application is the largest and most interesting consumer of adhesives.
Epoxies represent more than 70% of the adhesive demand. Exterior coatings for
the turbine pods, steel support structure and exterior blade surfaces are one-
or two-part polyurethanes. Sealants represent a smaller use.
Figure 4. Cost Comparison
Solar PV Panels
from silicon wafers, glass, plastics, and metal frames, solar panels consume
formulated adhesives, sealants, and coatings. Hot-melt adhesives are used in
bonding the wafers and other components, while sealants find use in
weatherproofing the assembly. Specialty clear plastics (e.g., polycarbonate,
ABS, etc.) protect the wafers.
Figure 5. Generic Products Used for Bonding, Sealing and Coating
Though the extent and importance of their use varies, adhesives, coatings and
sealants are key components in the manufacture of all alternative energy
options. A list of generic products used for bonding, sealing and coating are
shown in Figure 5. Adhesive and sealant consumption in the U.S. market was
estimated to be
50 million lbs in 2009 for all alternative energy types. Annual growth for
adhesives and sealants varies, but it is in the 10-12% range in terms of value
and 8-9% on formulated product demand.
The market is still new and subject to vagaries in funding, consumer acceptance
and site installation approvals. Most of the alternative energy options are in
their early development stages and depend on the availability of funding,
production support equipment (e.g., batteries), distribution networks, local
property restrictions, and other governmental regulations. The future for
alternative energy will need consumer acceptance and government support, along
with the development of new products, to meet ever-expanding needs.