Two Local Companies to Offer Solar Power at Oahu Community

Market Wire, March, 2008

D.R. Horton-Schuler Division's new Kahiwelo at Makakilo community will soon be using the sun to help provide electricity to its homes. Kahiwelo, which means "place of the setting sun" in Hawaiian, is D.R. Horton-Schuler Division's latest community in Makakilo.

D.R. Horton-Schuler Division, a wholly owned subsidiary of D.R. Horton, Inc. (NYSE: DHI), and Hoku Solar, Inc., a wholly owned subsidiary of Hoku Scientific, Inc. (NASDAQ: HOKU), have joined in a marketing program to offer two kilowatt photovoltaic (PV) systems to homebuyers at Kahiwelo at Makakilo.

PV technology converts solar energy into electricity with little impact on the environment. PV technology also offers the opportunity for 'net-metering,' or 'moving the meter backwards' when the PV system is producing more electricity than the home is using.

Homes at Kahiwelo at Makakilo will also be offered with solar water heating systems and, further, with features qualifying them as "HECO Bronze" under Hawaiian Electric Industries' recently announced sustainable housing programs. Meeting the bronze standards includes installing ENERGY STAR ceiling fans, ENERGY STAR compact fluorescent lamps and energy efficient air conditioners. The PV systems exceed the "HECO Bronze" standard and reflect D.R. Horton-Schuler Division's commitment to sustainable housing design.

"D.R. Horton-Schuler Division is excited and proud to enter into this arrangement with Hoku Solar, like us one of the state's home-grown success stories, and we hope this is the first of many communities in which we join forces," said Mike Jones, division president. "Both of our companies have a strong commitment to the islands. Offering our homebuyers this kind of innovative technology is part of our dedication to creating a long-term, sustainable future for Hawaii, while delivering an immediate cost savings opportunity to local families."

"D.R. Horton-Schuler Division is demonstrating its community leadership by promoting PV systems for homeowners of Kahiwelo at Makakilo," said Dustin Shindo, chief executive officer of Hoku Scientific. "We're pleased to be working with D.R. Horton on this important and exciting project."

Kahiwelo at Makakilo homebuyers who purchase the PV systems may benefit from Federal and state tax credits. Additionally, Hoku Scientific estimates that owners of the PV systems could potentially save as much as $25,000 over 25 years as the cost of electricity continues to increase.

Kahiwelo at Makakilo is planned to consist of 474 single-family homes and is scheduled to be built-out through 2015. Please call D.R. Horton-Schuler Division at (808) 672-7533 for more information about Kahiwelo at Makakilo.

About D.R. Horton, Inc.

D.R. Horton, Inc., "America's Builder," is the largest homebuilder in the United States, delivering more than 41,000 homes in its fiscal year ended September 30, 2007. Founded in 1978 in Fort Worth, Texas, D.R. Horton has operations in 82 markets in 27 states in the Northeast, Midwest, Southeast, South Central, Southwest, California and West regions of the United States. The Company is engaged in the construction and sale of high quality homes with sales prices ranging from $90,000 to over $900,000. D.R. Horton also provides mortgage financing and title services for homebuyers through its mortgage and title subsidiaries.

About Hoku Scientific, Inc.

Hoku Scientific, Inc. (NASDAQ: HOKU) is a diversified clean energy technologies company with three business units: Hoku Materials, Hoku Solar and Hoku Fuel Cells. Hoku Materials plans to manufacture, market, and sell polysilicon for the solar market from its plant currently under construction in Pocatello, Idaho. Hoku Solar is a provider of turnkey photovoltaic systems in Hawaii. Hoku Fuel Cells has developed proprietary fuel cell membranes and membrane electrode assemblies for stationary and automotive proton exchange membrane fuel cells. For more information visit www.hokuscientific.com .

Hoku® and Hoku Scientific® are registered trademarks and Hoku Solar(TM) is a trademark of Hoku Scientific, Inc. Hoku Materials is a trademark of Hoku Materials, Inc. All rights reserved. All other trademarks and service marks used in this press release are the property of their respective owners.

For More Information Contact: Jill Bona Bennet Group Strategic Communications Phone: 808-531-6087, ext. 107