APS Plans Largest PVConcentrator Project

October 22, 2001

Source: EPRI
http://www.epri.com/journal/details.asp?id=130&doctype=features

Arizona Public Service Company (APS) is planning the world’s largest high-concentration solar photovoltaic (HCPV) project, using commercially available technology that evolved from research and development supported in large part by EPRI. APS plans to install 500 kW of distributed, 25-kW sun-tracking HCPV arrays at multiple sites in Arizona this year. The plans were
announced in April by APS and Amonix Incorporated of Torrance, California, which developed and patented the high-efficiency, potentially low-cost utility-grade PV generating technology.

Amonix’s fifty-five-ft (16.8-m) wide, forty-five-ft (13.7-m) tall HCPV arrays are comprised of five MegaModule™ blocks, each rated 5 kW and mounted on a two-axis drive-structure that tracks the sun with high precision. Molded acrylic Fresnel lenses concentrate the sun’s rays by a factor of 250 onto small-area, point-contact silicon solar cells, which originated from EPRI-funded work by researchers at Stanford University in a ten-year program from the late 1970s to the late 1980s. During that time, APS was among five EPRI-member companies that participated in a collaborative project to supplement HCPV funding.

With an overall efficiency converting sunlight to direct current that exceeds seventeen percent, Amonix’s solar
array is projected to cost less than two dollars per watt when manufactured in large volume. Achieving such
production costs would make solar-generated electricity more competitive with conventional sources and open
the way to broader application and market penetration.

The first 100 kW of APS’s HCPV project came on line on April 5, 2001, with the dedication of four 25-kW
arrays at the Glendale (Arizona) Municipal Airport. An additional 400 kW, or sixteen additional HCPV arrays,
are planned for installation at other locations this year. The Glendale installation—along with two others in
Prescott and Gilbert that involve different PV technology—brought APS’ total installed solar generating
capacity to nearly 1 MW. The utility says it plans to have another megawatt of solar generating capacity
installed by the end of 2001.

"We are pleased to reach the one megawatt milestone with the dedication of these three plants, but it’s only
the beginning," says Ed Fox, APS vice president for communications, environment, and safety. "With the
energy shortages faced across the country and especially the West, every kilowatt of power we can generate
is important. These plants showcase our commitment to developing earth-friendly, renewable energy
resources."

Herb Hayden, APS solar program coordinator, notes that the utility—the largest subsidiary of Pinnacle West
Capital Corporation—has worked with Amonix for several years to develop the HCPV technology and
field-tested an earlier model of the Amonix array. "We’re pleased to be constructing and operating these first
commercial solar power generating facilities, and we’re confident this installation will demonstrate that
high-concentration PV is ready for large-scale commercial use."

When completed and fully operating, the HCPV installations will generate over 1,000 megawatt-hours per year.
Their output will be fed into APS’s electrical grid and displace an equivalent amount of electricity that would
have been generated by more traditional methods. All of the utility’s solar plants are financed in part by APS
and nearly 2500 customers participating as APS Solar Partners, who each pay $2.64 per month to have fifteen
kilowatthours of their electricity needs generated by solar power. Additional funding support is provided by the
U.S. Department of Energy through the Utility Photovoltaic Group.

Amonix advanced its HCPV technology from concept to commercial status through early collaboration with
EPRI and with support from DOE, including the National Renewable Energy Laboratory and Sandia National
Laboratory. "Our technology has an opportunity to play a major role in solving our country’s energy crisis,"
says Vahan Garboushian, president and founder of Amonix. "Our system can be readily manufactured in
volume and has great potential to be the world’s lowest-cost solar option."

Amonix’s HCPV technology is well-suited to high-volume production that can be easily ramped up as demand
for solar electricity increases. As with most manufacturing industries, such as automotive and electronics, unit
costs decline dramatically with increasing production. These factors position Amonix’s systems well for
producing large amounts of solar electricity.

"Environmental benefits and cost are both important factors that must be balanced, which is why APS has
been so supportive of solar development," according to Hayden. "We’re excited about the potential that
Amonix and its high-concentration PV have as a large-scale solar generation resource."

Tom Tanton, EPRI general manager for renewables and hydropower, calls the success of Amonix's HCPV
technology "an excellent example of fruit born through the determination and vision of collaborative research,
development, and demonstration. EPRI is proud of our contribution to this outcome."

For more information, contact Eric Dominguez at Amonix, edominguez@amonix.com,
310-325-8091, or Tom Tanton, ttanton@epri.com, 650-855-2470.

Photo: Amonix concentrator arrays installed at the Glendale, Arizona, municipal airport. Courtesy Amonix.