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This paper investigated the artificial neural network (ANN) modeling to forecast the one-hour ahead global and diffuse solar radiation using the observed data during 2019-2021 at a meteorological station in Bangkok, Thailand. Results from the statistical analysis portrayed the abundance of the tropical solar radiation and its large variation all year round. As a step to move advance the renewable energy use of the solar radiation at the location, the ANN forecasting models were proposed for all climatic conditions. The model input were the ambient temperature, solar elevation, and an insolation parameter namely normalized global solar radiation. The model performance was assessed by using the two statistic parameters: normalized mean bias error (nMBE), and normalized root mean square error (nRMSE). The results showed that the ANN models could forecast the global radiation with the nMBE of 1.79% and nRMSE of 26.20%. For the diffuse radiation forecast, the nMBE and nRMSE of the models were obtained at 7.78% and 36.21%, respectively. In order to demonstrate a benefit of the two developed ANN models, their forecasted horizontal data were employed to further predict the total solar radiation on vertical plane. Benchmarked with the smart persistence model, the developed ANN models possessed the higher forecasting accuracy for all weather conditions. [ABSTRACT FROM AUTHOR]

Urban settlements are home to the greatest levels of greenhouse gas emissions and energy consumption globally, with unprecedented rates of urban expansion occurring today. With the majority of global urbanization occurring along the periphery of urban areas in developing countries, investigation of 'green' building practices designed specifically for 'peri-urban' regions is critical for a low-emitting future society. This study assesses a state-of-the-art residence designed for a middle-class family of four residing in the peri-urban region of Bangkok, Thailand. The residence employs both demand-side management strategies and low-emitting energy supply technology to achieve energy-positive status. To elucidate the influence that key design decisions have on the life cycle sustainability of the home, several variants of the residence are modeled. A process-based life cycle assessment consistent with the International Organization for Standardization (ISO) 14044:2006 standard and following ReCiPe Midpoint life cycle impact assessment methodology is used to quantify the life cycle impacts per square meter of conditioned residence floor area for climate change (582 kilograms [kg] carbon dioxide equivalent), terrestrial acidification (4.01 kg sulfur dioxide equivalent), freshwater eutrophication (30.4 grams phosphorous equivalent), fossil depletion (362 kg iron equivalent), and metal depletion (186 kg oil equivalent) impacts. We model multiple scenarios in which varying proportions of Bangkok's peri-urban detached housing demand are fulfilled by the energy-positive residence variants. Under the best-case replacement scenario (i.e., 100% replacement of future peri-urban detached housing), significant reductions are achieved across the life cycle climate change (80%), terrestrial acidification (82%), and fossil depletion (81%) impact categories for the steel-framed, energy-positive residence. [ABSTRACT FROM AUTHOR]

An automated blind can provide energy saving and better comfort. To obtain these benefits a computer program that is able to calculate interior illuminance, heat gain, glare discomfort and thermal comfort has been developed. The thermal performance of the window system was investigated. From the study it is found that installing a venetian blind in between the double-pane glass window causes a significant reduction in heat gain compared to the plain glass window. The heat gain through the window system in the shortwave part of the radiation is analyzed. The slat reflectance, slat angle and solar profile angle are the major affect on the shortwave part of solar heat gain coefficient. The blind using a lower value of slat reflectance has a lower shortwave part of solar heat gain coefficient. The effective solar heat gain coefficient (SHGC) and the effective overall heat transfer coefficient (U) for the double-pane glassed window with enclosed horizontal slats was developed. These SHGC and U value can be used with the equation to calculate the Overall Thermal Transfer Value (OTTV) of Thailand's building energy code to evaluate a building that use the double-pane glassed window with enclosed venetian blind. [ABSTRACT FROM AUTHOR]

The tropical sky is highly luminous. This gives rise to expectation of its high potential for daylighting. The availability of an accurate luminance distribution for daylight from the sky would help advance the movement for daylighting. On the other hand, accurate radiance distribution model is also needed to help manage the undesirable heat gain due to solar radiation penetration in airconditioned buildings. Towards these ends, eight luminance and radiance distribution models were evaluated against luminance and radiance measurements recorded in a station located north of Bangkok. Due to prevalence of intermediate and cloudy sky conditions in the tropical region, attention was paid to seeking models that could perform well under these conditions. It turns out that a number of models are acceptable, but no single model performs distinctively well for the prevalent conditions. [ABSTRACT FROM AUTHOR]