SunEdison Expands in Italy With 12 New Solar Parks; Completes 47 Million Euro Financing Deal

MILAN, May 4, 2010 - SunEdison, a division of MEMC Electronic Materials, Inc.
(NYSE: WFR), today announced plans to complete 12 one-megawatt (MW) solar
energy plants in the province of Lecce, Apulia in Italy, and announced a
47-million-euro financing deal with Norddeutsche Landesbank Girozentale in
Germany.

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"The announcement of these projects, which follows another
major project announced recently by SunEdison in Italy - demonstrates our
deep expertise as developers of a wide range of solar energy plants, from
rooftop retail facilities to large, ground-mount utility-scale operations,"
said Carlos Domenech, president, SunEdison. "Given our financing strength and
project skills, SunEdison plans to continue to expand rapidly in Italy and in
our other targeted growth areas in the United States, Canada and other
European countries."

SunEdison earlier announced a 72 MW photovoltaic solar plant
to be built in northeastern Italy near the town of Rovigo as the largest
solar energy plant in Europe.

To develop the Apulia projects, SunEdison signed a 47 million
euro financing deal with NORD LB - Norddeutsche Landesbank - a leading bank
in Germany. Vinod Mukani, Head of Americas Solar Origination for NORD/LB,
said: "We are pleased to partner with SunEdison to provide financing for
these projects and to support SunEdison in their development plans across the
globe. This financing further highlights NORD LB's client focused strategy,
advisory capabilities and its commitment towards renewable energy sector".
Heiko Ludwig, Head of Energy Origination Europe for NORD/LB added,
"Considering the intricate nature of the financing for the portfolio, NORD LB
advised SunEdison on an efficient and financeable cross border structure for
its Italian portfolio. The financing of renewable energies is one of the NORD
LB Group's key areas of business growth and the partnership with SunEdison
allows us to demonstrate again our leading position in project financing in
the solar sector across the world".

"Our goal is to continue to increase our presence and our
solar electric power interconnections in Italy over the course of the year,"
said Pancho Perez, General Manager of Europe and MENA Region for SunEdison.
"We have very strong project financing and development capabilities and are
continuing to expand our relationships with solar channel partners throughout
Italy"

The SunEdison Lecce solar parks will generate power for more
than 3,300 homes during their first year of operation while reducing carbon
dioxide emissions that are equivalent to taking 2,000 cars off the road.
Besides the dramatic environmental advantages, the new solar plants will also
create construction and plant operating jobs in the region.

Seven of the Lecce plants are already fully operational and
were grid connected and sold in the first quarter of 2010. The other five
plants are under construction and expected to be completed and operational by
the third quarter. The 47-million-euro financing deal with Nord LB covers the
majority of the one-megawatt plants.

About SunEdison

SunEdison is a global provider of solar-energy services. The
company finances, installs and operates distributed power plants using proven
photovoltaic technologies, delivering fully managed, predictably priced solar
energy services for its commercial, government and utility customers. In
2009, SunEdison delivered more kilowatt hours (kWh) of energy than any other
solar services provider in North America. For more information about
SunEdison, please visit www.sunedison.com.

About MEMC

MEMC is a global leader in the manufacture and sale of wafers
and related intermediate products to the semiconductor and solar industries.
MEMC has been a pioneer in the design and development of silicon wafer
technologies for 50 years. With R&D and manufacturing facilities in the U.S.,
Europe, and Asia, MEMC enables the next generation of high-performance
semiconductor devices and solar cells. Through its SunEdison division, MEMC
is also a developer of solar power projects and North America's largest solar
energy services provider.

MEMC's common stock is listed on the New York Stock Exchange
under the symbol "WFR" and is included in the S&P 500 Index. For more
information about MEMC, please visit www.memc.com.

About NORD/LB (Norddeutsche Landesbank Girozentale)

Based in Hannover, Germany, Norddeutsche Landesbank
Girozentale (Nord/LB) has grown to be Germany's tenth largest financial
institution with roots going back to 1765. The Bank offers a range of
financial services including Project Finance, Real Estate Lending, Asset
Backed Finance, Treasury and Capital Markets functions. The financing of
renewable energies is one of the Nord/LB Group's key areas of business
growth. With a volume of around 3.5 billion Euros, the Group is already one
of the leading finance providers in this sector. Nord/LB has an excellent
track record in the solar sector that spans the entire globe, from rooftop &
ground mount solar projects in Germany, Canada and US, to larger ground mount
solar farms as well as panel & glass manufacturing facilities. More
information can be found at www.nordlb.com

Forward-Looking Statements

Certain matters discussed in this news release are forward-looking
statements, including that five of the plants are expected to be completed
and operational by the third quarter of 2010. Such statements involve certain
risks and uncertainties that could cause actual results to differ materially
from those in the forward-looking statements. Potential risks and
uncertainties include delays or interruptions in construction of the power
plants, including interruptions due to weather or delays in the delivery of
transformers, modules or other components; delays due to challenges against
the permits or authorizations for the power plants by governmental or third
parties; delays in interconnection of the power plants to the electricity
grid; changes in the applicable regulatory system, including any incentives
for production of electricity for solar power plants; and other risks
described in MEMC's filings with the Securities and Exchange Commission.
These forward-looking statements represent MEMC's and SunEdison's judgment as
of the date of this release. MEMC and SunEdison disclaim, however, any intent
or obligation to update these forward-looking statements.

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Media Contacts: Virginia Amador, SunEdison Italy, +34-608-943-101, vamador at sunedison.com; Brad Oswald, SunEdison Corporate, +1-443-909-7200, boswald at sunedison.com; Bill Michalek, MEMC Electronic Materials, Inc., +1-636-474-5443