Natural cooling via roof water spray
Source: UFTO
Date: 7/11/97    Record No.: 10502
Contact: Mark Berman or Richard Bourne
Roof Science Corp., Davis Energy Group, Davis CA

Natural cooling via roof water spray
Date: Fri, 11 Jul 1997 13:19:33 -0700

Natural cooling via roof water spray

Roof Science Corp. has developed a system called WhiteCap which can meet 50%-100% of a commercial building cooling loads in arid or semi-arid climates, by radiating heat to the night sky to cool the roof and water which is sprayed on the roof. (Note this is radiative, not evaporative cooling.) The cooled water is collected in a storage tank to provide cooling during the next day. It thus substantially reduces both energy and peak electric demand for indoor comfort control.

In the last few months, NREL committed to completing their test case study at the Nogales Border Station, under the DOE New Technology Demonstration Program. Results will be promulgated among 2,000 federal energy managers. Also, three private developers have committed to include WhiteCap in new buildings.

The company projects profitability in 2-3 years, and is seeking investment and business partners.

Mark Berman or Richard Bourne
Roof Science Corp., Davis Energy Group, Davis CA

The following is excerpted from Roof Science's business plan:

WhiteCap was developed by the Davis Energy Group (DEG) with support from the California Energy Commission, the U.S. Department of Energy, SMUD, and PG&E. The systems use a natural cooling phenomenon to satisfy 50 to 100% of commercial building cooling loads in dry climates. The clear summer night sky is cold; 20-30 F equivalent as a receiver of radiant energy from the earth. Water sprayed at night on roofs facing the sky can often be cooled to 55 F when daytime temperatures exceed 100 F. After night-cooling on the roof, the chilled water is filtered and stored for next-day use. The three WhiteCap system types facilitate integration with most non-residential buildings. Economics are very favorable, generating zero to three year paybacks. Added fire safety, automatic roof cleaning, and utility incentives which recognize peak load reduction further enhance WhiteCap value. WhiteCap also offers substantial environmental benefits by reducing ozone depletion and global warming.

Technology Status: Seven full scale WhiteCap projects are operating as of April, 1997. The largest is a 27,000 ft2 state office building in Los Angeles. Four have monitoring systems which generate continuing performance data verifying effective cooling performance. Recent projects have shifted from "on-roof" to more marketable "off-roof" water storage. This change has required re-engineering and testing of some components. New designs promise even better performance, reduced costs, and additional patent protection. The most immediate technology goal is to demonstrate the new designs in several large (50,000 ft2+) "flagship" projects.

The Market: The primary WhiteCap market is new and retrofit low-rise buildings with low-slope roofs in the Western U. S. This is a very large market; the new construction opportunity alone is roughly 100 million square feet per year in the Western US. The highest growth rates are occurring in locations where high cooling loads offer significant opportunities for WhiteCap. Many existing buildings with central systems are WhiteCap candidates because CFC-based cooling systems must be replaced per the MontreaI Protocol. Underlying market conditions for RSC should remain positive, and electric utility deregulation should enhance WhiteCap's prospects.

Competition: RSC has relatively strong patent protection on WhiteCap technologies and there are no direct WhiteCap competitors. Two patents have issued and two other applications are being prepared. Inertia is strong in the construction industry, and conventional systems will continue to be strong competitors in the future. Electric utility and government activities are expected to influence the industry toward WhiteCap.

The Company: RSC was formed in 1992 as an "incubator" firm in the Sacramento Technology Development Center, to move WhiteCap from R&D status to a commercialized product. After five years of part-time continuing development and demonstration, the company is now poised for success.

Marketing Strategy: RSC provides engineering services and specialty components for WhiteCap projects. Initial marketing efforts have generated a clear picture of preferred markets which are, in ranked order: (l) local new office projects; (2) Federal and State government retrofit projects; (3) "high tech" industrial facilities; (4) "green" buildings, and (5) schools. Marketing efforts will continue to focus on key Northern California projects with profit potential through 1998. RSC will use current contacts with major commercial building firms to generate new sales. Free publicity, sales agents, advertising, and licensees will be all be used to rapidly increase sales beginning in 1999.

Topics: buildings, end use