01366nas a2200169 4500008004100000022001500041245010600056210006900162260001200231300001200243490000700255520079100262100002301053700002301076700002101099856007601120 1999 eng d a0021-8979 00aRefractive Index Changes of Pd-Coated Magnesium Ianthanide Switchable Mirrors Upon Hydrogen Insertion0 aRefractive Index Changes of PdCoated Magnesium Ianthanide Switch c01/1999 a408-4130 v853 a

The optical effect upon insertion of hydrogen into Pd-coated magnesium lanthanide switchable mirrors is investigated in terms of the changes of their complex refractive indices. A significant change in the optical constants of LnMg layers is seen between the as-deposited state and the dehydrided state after one cycle. Furthermore, the optical effect of switching the Pd cap layer to a PdH cap layer was determined. It is shown that the Pd layer mainly limits the visible transmittance of the hydrided stack to about 35%-40%. Whereas the extinction coefficient of dehydrided LnMg layers at 550 nm is between 2.2 and 3.1, it is as low 10-4 as in the transparent state. This is of great promise to applications requiring large optical contrast (e.g., optical switches).

1 avon Rottkay, Klaus1 aRubin, Michael, D.1 aDuine, Peter, A. uhttps://facades.lbl.gov/publications/refractive-index-changes-pd-coated01718nas a2200157 4500008004100000050001500041245006500056210006500121260002900186520117200215100002501387700002901412700002301441700001801464856007801482 1995 eng d aLBNL-4168000aRecent Technical Improvements to the WINDOW Computer Program0 aRecent Technical Improvements to the WINDOW Computer Program aToronto, Canadac06/19953 a

The WINDOW series of computer programs has been used since 1985 to model the thermal and optical properties of windows. Each succeeding version of WINDOW has brought its user base new technical capabilities, improvements to the user interface, and greater accuracy. Technical improvements to the current version, which will be released as version 5, are at first being released as stand-alone programs. This paper summarizes the capabilities and algorithms of two of these programs, THERM and LAMINATE. A third stand alone program, RESFEN, which calculates the annual energy effects of specific windows in a typical house throughout the US, will also be incorporated into WINDOW 5; because this program is already in use and documented, it is not discussed in this paper. THERM allows the user to evaluate two dimensional (2-D) heat transfer effects through the solid elements of a window while LAMINATE determines the optical properties of an individual glazing layer with an applied film. Both of these programs are undergoing final development at the time of this writing and will be released as separate programs before they are incorporated into WINDOW 5.

1 aArasteh, Dariush, K.1 aFinlayson, Elizabeth, U.1 aRubin, Michael, D.1 aSadlier, John uhttps://facades.lbl.gov/publications/recent-technical-improvements-window02457nas a2200145 4500008004100000050001400041245008800055210006900143260003400212520192400246100002102170700002302191700002702214856007002241 1995 eng d aLBL-3721100aReducing Residential Cooling Requirements Through the Use of Electrochromic Windows0 aReducing Residential Cooling Requirements Through the Use of Ele aClearwater Beach, FLc12/19953 a

This paper presents the results of a study investigating the energy performance of electrochromic windows in a prototypical residential building under a variety of state switching control strategies. We used the DOE-2.1E energy simulation program to analyze the annual cooling energy and peak demand as a function of glazing type, size, and electrochromic control strategy. A single-story ranch-style home located in the cooling-dominated locations of Miami, FL and Phoenix, AZ was simulated. Electrochromic control strategies analyzed were based on incident total solar radiation, space cooling load, and outside air temperature. Our results show that an electrochromic material with a high reflectance in the colored state provides the best performance for all control strategies. On the other hand, electrochromic switching using space cooling load provides the best performance for all the electrochrornic materials. The performance of the incident total solar radiation control strategy varies as a function of the values of solar radiation which trigger the bleached and colored states of the electrochromic (setpoint range); i.e., required cooling decreases as the setpoint range decreases; also, performance differences among electrochromics increases. The setpoint range of outside air temperature control of electrochromics must relate to the ambient weather conditions prevalent in a particular location. If the setpoint range is too large, electrochromic cooling performance is very poor. Electrochromics compare favorably to conventional low-E clear glazings that have high solar heat gain coefficients that are used with overhangs. However, low-E tinted glazings with low solar heat gain coefficients can outperform certain electrochromics. Overhangs should be considered as a design option for electrochromics whose state properties do not change significantly between bleached and colored states.

1 aSullivan, Robert1 aRubin, Michael, D.1 aSelkowitz, Stephen, E. uhttps://facades.lbl.gov/publications/reducing-residential-cooling01798nas a2200157 4500008004100000050001400041245005800055210005600113260003100169520127800200100002701478700002301505700002101528700002101549856007001570 1994 eng d aLBL-3548600aA Review of Electrochromic Window Performance Factors0 aReview of Electrochromic Window Performance Factors aFreiburg, Germanyc04/19943 a

The performance factors which will influence the market acceptance of electrochromic windows are reviewed. A set of data representing the optical properties of existing and foreseeable electrochromic window devices was generated. The issue of reflective versus absorbing electrochromics was explored. This data was used in the DOE 2.1 building energy model to calculate the expected energy savings compared to conventional glazings. The effects of several different control strategies were tested. Significant energy and peak electric demand benefits were obtained for some electrochromic types. Use of predictive control algorithms to optimize cooling control may result in greater energy savings. Initial economic results considering annual savings, cooling equipment cost savings, and electrochromic window costs are presented. Calculations of thermal and visual comfort show additional benefits from electrochromics but more work is needed to quantify their importance. The design freedom and aesthetic possibilities of these dynamic glazings should provide additional market benefits, but their impact is difficult to assess at this time. Ultimately, a full assessment of the market viability of electrochromics must consider the impacts of all of these issues.

1 aSelkowitz, Stephen, E.1 aRubin, Michael, D.1 aLee, Eleanor, S.1 aSullivan, Robert uhttps://facades.lbl.gov/publications/review-electrochromic-window