Edition #3

Currents of Change

Rising energy bills, coupled with a growing awareness of the environmental impact of burning fossil fuels, have made finding alternative, renewable energy sources a critical priority here in the United States and abroad.

From tidal turbines submerged in Manhattan’s East River to wind farms in the western states, sustainable energy solutions across America share one important element — they all rely on copper and its electrical conducting properties to generate and distribute electricity.

It’s a Windy World
Most of the energy plants operating in the USA burn coal to power mechanical systems that generate electricity. However, the use of natural, renewable energy resources like the sun and wind are on the rise.

Wind energy, in particular, has been deemed the fastest growing source of power generation worldwide, according to the American Wind Energy Association (AWEA), which lists the United States second only to Germany in wind-based power capabilities.

While the concept of using wind power is not new, the sleek, aerodynamic designs of today’s wind turbines bear little resemblance to the rural windmills once used to pump water or grind grain.

Mounted on towers 235- to 300-feet tall to take advantage of faster and less turbulent wind, a modern wind turbine generally has three propeller-like blades attached to a rotor. When the rotor is in motion, it turns a drive shaft that spins a mechanical arm wound with copper wire. Magnets placed on either side of the spinning arm react to the motion of the copper wire, generating an electric current.

Copper is used in even greater quantities to connect wind turbines grouped together in “wind farms” to provide power for entire cities.

Underwater Turbines in the East River
Copper plays a similar role in the world’s first farm of tide-powered turbines in New York City’s East River.

A series of 15-foot tall turbines are being installed in the river, where rapid water currents — among the fastest on the East Coast —will one day, hopefully, power generators that will produce 10 megawatts of electricity (enough to power 8,000 homes), when the project is completed in 2006.

The $20 million project, currently being installed by Verdant Power of Virginia, is expected to employ up to 300 turbines mounted on pilings affixed to the river basin some 30 to 40 feet below the surface. The propellers are about eight feet below the water’s surface and move slowly enough that they do not harm aquatic life.

With support from the New York State Energy Research and Development Authority (NYSERDA), Verdant ran a five-week trial in 2002 using one turbine. The project is currently in its second phase — with six turbines now operating in the river that will provide energy to residents and businesses on nearby Roosevelt Island.

Solar Power Advances
New advances in solar energy technology include the discovery of a thin-film technology made from Copper Indium Diselenide (CuInSe2 or CIS), which has been shown to increase the energy efficiency of solar cells. This new type of cell costs up to 10 times less than current silicon-based photovoltaic cells and has the potential to make solar power more attractive to architects and builders.

To learn more about some of the renewable energy sources cited in this article, go to www.copper.org/resources/cutopics/Ct93/generation.html.

BIOSPHERE 2 DEPENDS ON COPPER

In Southern Arizona, just outside Tucson, lies a massive glass building as big as an airport hanger, stretching across 3.15 acres of desert. The structure houses seven ecosystems, including a desert, rainforest and one-million-gallon ocean with its own coral reef.

Modeled after Earth, it was designed to be completely self-sustaining and capable of supporting human, animal and plant life. In the early 1990s, eight volunteers signed on to live inside the dome for two years — completely sealed off from the outside world.

You may have heard of this well-known research project, Biosphere 2. But do you know the important role that copper plays in its operation?

Due to its excellent heat transfer properties and reliability, copper tubing is used in climate control — a big job in the biosphere, considering that the all-glass structure attracts a lot of sunlight.

“Biosphere 2 is a large solar collector. We don’t need to add heat — we are always removing it,” says Clark Reddin, facilities director for Biosphere 2.

Copper tubing is used in the biosphere’s extensive air handling and heat exchange systems, says Reddin. Copper tubes filled with chilled water cool the air, while simultaneously absorbing the sun’s radiant heat inside the dome. Copper is also used in the electrical wiring, motors and fans needed to distribute the cooler air.

Engineers and scientists supervise the biosphere’s life systems using 1,000 sensors networked through copper Category 5e telecommunications cable. In addition, special copper cables are used in the ocean biome to monitor and control temperatures and carbon dioxide levels, ensuring the health of the fish and coral living in the waters.

Currently, Biosphere 2 is a popular tourist attraction. But it will take a long time for it to surpass the popularity of Biosphere 1 — Planet Earth.

COMPUTER CHIPS BUILT FOR SPEED

The mantra of the Technology Age is clear — the faster the better. In a world of high-speed trains, high-speed digital cameras and highspeed Internet access, the race is on for the next technological advance. But the latest BIG thing is a tiny computer chip made with copper.

This isn’t exactly new territory. IBM first caught on to the benefits of copper in 1997, when it replaced aluminum pathways with copper in some of its computer chips. Since then, Motorola, Texas Instruments, AMD, Intel and other manufacturers have taken advantage of copper’s physical properties.

Why use copper wire paths to link transistors in chips? For starters, copper caters to the need for speed. Its superior electrical conductivity allows conductors to be reduced in size, providing for greater circuit integration and shorter circuit pathways. That results in faster operating speeds and enables more than 400 million transistors to fit on a single chip — now that’s BIG.

Copper is the answer to another problem plaguing the computer industry: heat. The more components on a chip, the hotter it gets, and heat can damage electronic devices and cause data loss. Since copper dissipates heat more rapidly than aluminum, chips wired with copper can run cooler than ever before. A couple of added bonuses: chips incorporating copper, rather than aluminum, require less power to operate and are cheaper to produce.

Biosphere 2 in the Arizona desert.
Photo Courtesy of Biosphere 2.

Click here for a Hi-Resolution version of this picture.

Resources:
For more information on the companies mentioned in this newsletter go to:

www.awea.org
American Wind Energy Association

www.nrel.gov
U.S. Government’s National Renewable Energy Laboratory (NREL)

www.nrel.gov/ncpv
U.S. Department of Energy National Center for Photovoltaics

www.eere.energy.gov
U.S. Department of Energy’s Office of Energy Efficiency and Renewable
Energy (DOE/EERE)

www.eere.energy.gov/solar/
Solar Energy Technologies Program of the DOE/EERE

www.bio2.com
Biosphere 2

www.verdantpower.com
Verdant Power

The information presented in Discover Copper is provided by the Copper Development Association for editorial re-use. This material is verifiable and accurate as of the date of publication. Additional comment, contact information or attribution may be obtained from the sources noted, or by contacting CDA Communications Manager Ken Geremia (212-251-7209, kgeremia@cda.copper.org). The Copper Development Association Inc., 260 Madison Avenue, New York, NY 10016, is affiliated with the International Copper Association and is the information, education, market and technical development arm of the copper, brass and bronze industry in the United States.