SunPower and Etrion Complete Sale of Italian Power Plants

Etrion Acquires 28-Megawatt Montalto di Castro Solar Park

GENEVA, October 4, 2010 - SunPower Corp. (Nasdaq: SPWRA, SPWRB) today announced that Etrion
Corporation (TSX: ETX), an independent solar power producer, has completed
the previously announced definitive sale and purchase agreements to acquire
the equity in the first two phases of Montalto di Castro solar park, Italy's
largest solar photovoltaic (PV) power park, for approximately euro 49
million.

The acquisition of the 20-megawatt (MW) first phase of the project was
completed in August and the acquisition of the 8 MW second phase was
completed last week. SunPower will recognize the sale of the first phase of
the project as a return of capital, and will recognize revenue on the sale of
the second phase, including previously deferred engineering, procurement and
construction (EPC) revenue.

"With the closing of this acquisition, we are well on our way to
completing the monetization of 85 MWs in Italy this year," said SunPower CFO
Dennis Arriola. "SunPower's world-leading technology and proven performance
of more than 225 MWs of operational power plants in Europe has provided us
with a strong set of potential financing partners, including many new
participants to the solar market."

SunPower designed and built the 28 MW Montalto di Castro solar park in
the Lazio region of Italy near Rome, and will provide ongoing operations and
maintenance services. The 20 MW first phase was connected to the grid in
November 2009, several weeks ahead of schedule and was acquired by SunPower
upon the acquisition of SunRay Renewable Energy in May of 2010. The 8 MW
second phase was commissioned last month. An incremental 44 MW is planned to
be completed and monetized by the end of this year, bringing the total scale
of the solar park to 72 MW.

The Montalto di Castro solar park uses high-efficiency SunPower solar
panels, the most efficient panels commercially available, installed on a
SunPower(R) Tracker system. The Tracker follows the sun during the day and
delivers up to 25 percent more energy than fixed-tilt systems, while
significantly reducing land use requirements.

Worldwide, SunPower has more than 600 MW of solar power systems installed
or under contract, including more than 225 MW of operational power plants in
Europe.

About SunPower

Founded in 1985, SunPower Corp. (Nasdaq: SPWRA, SPWRB) designs,
manufactures and delivers the planet's most powerful solar technology broadly
available today. Residential, business, government and utility customers rely
on the company's experience and proven results to maximize return on
investment. With headquarters in San Jose, Calif., SunPower has offices in
North America, Europe, Australia and Asia. For more information, visit
www.sunpowercorp.com.

Editors' Note:

The capacity of power plants in this release is described in approximate
megawatts on an alternating current (AC) basis unless otherwise noted. On a
direct current (DC) basis, the first two phases of the Montalto di Castro
solar park are approximately 24 MW and 9 MW respectively in capacity. They
form part of a multi-phase solar park totaling approximately 85 MW (DC) in
capacity.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning
of the Private Securities Litigation Reform Act of 1995. Forward-looking
statements are statements that do not represent historical facts and may be
based on underlying assumptions. The company uses words and phrases such as
"will," "on our way," "potential" and "planned" to identify forward-looking
statements in this press release, including forward-looking statements
regarding: (a) nature of revenue recognition; (b) expected monetization of 85
MW in Italy in 2010; (c) the potential number of financing partners; and (d)
expected completion and monetization of an additional 44 MWs in the Montalto
solar park. Such forward-looking statements are based on information
available to the company as of the date of this release and involve a number
of risks and uncertainties, some beyond the company's control, that could
cause actual results to differ materially from those anticipated by these
forward-looking statements, including risks and uncertainties such as: (i)
construction difficulties or potential delays in the project implementation
process; (ii) unanticipated delays or difficulties securing necessary
permits, licenses or other governmental approvals or financing; (iii) the
risk of continuation of supply of products and components from suppliers;
(iv) unanticipated problems with deploying the system on the sites; (v)
general business and economic conditions, including seasonality of the
industry; (vi) growth trends in the solar power industry; (vii) the
continuation of governmental and related economic incentives promoting the
use of solar power; (viii) the improved availability of third-party financing
arrangements; (ix) the significant investment required to construct power
plants and the company's ability to sell or otherwise monetize solar power
plants; and (x) other risks described in the company's Annual Report on Form
10-K for the year ended January 3, 2010 and Quarterly Report on Form 10-Q for
the quarter ended July 4, 2010, and other filings with the Securities and
Exchange Commission. These forward-looking statements should not be relied
upon as representing the company's views as of any subsequent date, and the
company is under no obligation to, and expressly disclaims any responsibility
to, update or alter its forward-looking statements, whether as a result of
new information, future events or otherwise.

SunPower is a registered trademark of SunPower Corp. All other trademarks
are the property of their respective owners.

Ingrid Ekstrom, +1-510-260-8368, iekstrom at sunpowercorp.com or Christelle Huwiler, +41-22-304-15-93, Christelle.Huwiler at sunpowercorp.com