Harvard College

Hamilton Sundstrand Space Systems International, Inc.

Brian R Tull

Mark R Jaworowski

Eric Mazur

John W Steele

Durwood Mace Beringer

Mark T Winkler

Jerome D Varsik

Jesse Morenz

Photovoltaic devices (e.g., solar cells) are disclosed that include at least three radiation absorbing layers, each capable of absorbing radiation over a different wavelength range of the solar radiation spectrum. Any two of these three wavelength ranges can be partially overlapping, or alternatively they can be distinct. The layers are disposed relative to one another so as to form two junctions, each of which includes a depletion region. In some cases, the radiation absorbing layers can collectively absorb radiation over a wavelength range that spans at least about 60%, or 70%, or 80%, and preferably 90% of the solar radiation wavelength spectrum. By way of example, in some embodiments, one layer can exhibit significant absorption of solar radiation (e.g., it can absorb at least one radiation wavelength at an absorptance greater than about 90%) at wavelengths less than about 0.7 microns while another layer can exhibit significant absorption of the solar radiation at wavelengths in a range of about 0.7 microns to about 1 micron. The third layer can in turn exhibit a significant absorption of solar radiation at wavelengths greater than about 1 micron.

Multijunction photovoltaic device

An aqueous-based coolant for cooling and reducing corrosion potential in applications having high aluminum or nickel surface area to coolant volume ratios has a pH between 8 and 9 and includes about 35 weight % to about 65 weight % propylene glycol, about 1.0 weight % to about 4.0 weight % 2-ethylhexanoic acid, about 0.25 weight % to about 1.0 weight % sebacic acid, about 0.25 weight % to about 1.0 weight % benzoic acid and about 0.03 weight % to about 0.1 weight % molybdate oxyanion. A cooling system includes an aluminum or nickel surface and the aqueous-based coolant. A method of cooling a component surface containing aluminum or nickel includes delivering the aqueous-based coolant to the component surface and cooling the component surface with the aqueous-based coolant.

Aqueous based cooling of components having high surface area levels of aluminum or nickel

Growing community of inventors

West New York, NJ, United States of America

Brian R Tull