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This research attempts to develop a systematic method to address climate changes by studying temperature-humidity patterns as the two major meteorological parameters and to moderate these effects using a commercially available window film on interior windows of an office building with double-glazing. A three-floor educational building at Australian College of Kuwait (ACK) was equipped with temperature, humidity and illuminance sensors for two similar size offices, one with 3 M Neutral 20 window films. Total readings of 50,000 entries from each sensor was recorded every 3 min by a home-designed microprocessor-based logging system for three months of June, July, and August 2019. In parallel, the ACK building was simulated in EnergyPlus and DesignBuilder software and calibrated with the experimental measurements. Histograms and a probability density function (PDF) of temperature and humidity are built by a representative rational function as a model of main climate parameters variations. By examining min-mean-max values of data, it is observed that the office with window films has increased indoor humidity and, in most instances, reduced temperature by 2–5 °C compared to double-glazed bare windows which can significantly reduce cooling loads in extreme hot-arid climates. Simulation results are presented on the energy saved and the reduced CO2 footprints by applying the solar window films in the ACK building.

The electricity consumption in residential/office buildings corresponded to 45% of the total annual electricity demand in hot-arid climates. This accounted for 27.2 TWh of electricity consumption with 14.2 MWh/capita/year in Kuwait. In this research, four offices in an educational building were equipped with a meteorological data logging system using temperature, humidity, and illuminance sensors. All four offices had double-glazed windows. Moreover, two offices were equipped with two types of commercially available window films. Two million data were stored in iCloud using Wi-Fi and an Internet of Things (IoT) system for the 3 months of June, July, and August 2019. Here, histograms and the kernel density estimation (KDE) of temperature/humidity were analyzed and compared for the two offices with/without 3M Neutral 20 window films. Two floors of the same building consisting of 31 offices were also modeled and simulated to study energy saving and CO2 footprint reduction using various window films. The results of simulations for the month of July 2019 using SOL 101 and SOL 102 window films, respectively, showed that about 250 kg and 255 kg of production of CO2 could be reduced and energy saving counted for 416 and 422 kWh. Measurements from offices with 3M Neutral 20% and 3M Neutral 70% window films for the month of July 2019 indicated that the carbon footprint could be reduced by about 82 kg and 0.43 kg and energy saving counted for 147.11 and 0.71 kWh, respectively. It was observed that an annual energy saving and CO2 footprint reduction of 2.76% could be achieved using window films in a hot-arid climate.

This study examines the performance of solar window films installed on double-glazed windows of typical offices in actual working conditions in a hot and dry climate. Passive thin films stuck interiorly on double-glazed windows were used to affect various solaroptical impacts including energy saving, UV reduction, and increased thermal comfort. Real-time measurements of environmental parameters, including temperature, humidity, and luminous, were performed continuously in 5-minute intervals over three summer months of June, July, and August 2019 in Kuwait and data were stored automatically through a WiFi system. Arduino-type microprocessors and various temperature, humidity, Lux, and UV sensors were assembled and programmed to transfer and store data in real-time. Temporal and spectral analyses were conducted to compare the effects of the window films on these environmental parameters. It is evident that windows film has good potential to decrease interior temperature and its variability, to save energy and reduce CO 2 footprints, to save water by preserving interior humidity to level of human comfort, to restrict the solar UV rays to minimum level, and to reduce visual impacts of high solar luminous in hot-dry climates. The benefits and drawbacks of the selected windows film are discussed.

This work examines the solar performance of double-glazed windows in four offices in ACK buildings with and without solar window film in actual working conditions. Window films are passive thin films stick to the interior or exterior of windows to effect various solar-optical impacts including energy saving, UV reduction, and increased thermal comfort. For this study, the 3M Neutral 20 and 70 are selected which are made of multilayer nanofilms of 220 SAN25/THV 95-nm thick reflective layers. Real-time measurements of temperature, humidity, and luminous were conducted in 5 min intervals over the months of June, July, and August 2019 and data stored through WiFi system in iClouds. Arduino-type microprocessors and various temperature-humidity, and LUX sensors were assembled and programmed to transfer and store data in real time. Exploring and analyzing the data collected for four offices with and without window films in summer of Kuwait, it is evident that window film has good potential to save water by preserving interior humidity to the level of human comfort, decrease interior temperature to save energy and reduce CO2 footprints, to restrict the solar UV rays to minimum level, and to reduce visual impacts of high solar luminous. The benefits and drawbacks of the selected window films are discussed here for the weather condition of Kuwait.