• Energy Research

Abstract In the quest towards energy conservative building design thermal comfort must not be sacrificed. This paper explores energy conservation strategies and their impact on the thermal environment. Parametric variations in envelope design and HVAC operation on energy performance and thermal comfort of a typical commercial office building in Singapore are investigated. With proper plant operation, the resulting internal environment suffers no loss in comfort level, and the savings in energy arising from the various conservation measures are realistic. These measures are ranked according to their effectiveness, and provides valuable knowledge for achieving energy conservation without introducing occupant discomfort.

This paper presents the current state of the art regarding work performed related to the electric energy consumption for Information and Communication Technologies (ICTs) and Miscellaneous Electric Loads (MELs), in office and commercial buildings. Techniques used for measuring the energy consumption of office plug loads, and efforts for saving energy by using this equipment more rationally and efficiently are identified and categorized. Popular methods and techniques for energy metering are discussed, together with efforts to classify and benchmark office equipment. Our study reveals that many issues are still open in this domain, including more accurate, diverse and meaningful energy audits for longer time periods, taking into account device profiles, occupant behavior and environmental context. Finally, there is a need for a global consensus on benchmarking and performance metrics, as well as a need for a coordinated worldwide activity for gathering, sharing, analyzing, visualizing and exposing all the silos of information relating to plug loads in offices and commercial buildings.

High temperature cooling is gaining more attention in commercial buildings of the tropical climates where temperature and humidity is high all year round. In this air-water system, radiant-convective cooling is provided into conditioned space through using higher chilled water temperature compared to conventional all air system. Radiant cooling panel, radiant slab cooling, passive/active chilled beams are the main design strategies for implementing this concept into buildings. This paper reviewed and summarized the recent published papers on applications of high temperature cooling systems in tropical buildings. The reported outcomes and conclusions from these studies were extracted and discussed to get a better understanding on overall performance of the systems which are designed based on this concept. The potential energy saving of this strategy was estimated to be in the range of 6–41% depending on design strategies and operational scenarios of system. Comfortable and healthy indoor environment is achievable for this design when a parallel air system satisfies latent load and ventilation requirement of space. Low air movement was the only reported comfort concern for this design since locally acclimatized occupants in the tropics prefer higher air movement compared to dry and temperate climates. Regarding the parallel air system strategy, DOAS with ceiling supply-ceiling exhaust is suggested to be the best choice to be coupled with high temperature cooling system. In addition, incorporation of energy recovery systems like membrane based air to air heat exchanger into DOAS can improve the overall efficiency of this design.

The idea of far transfer effects in the cognitive sciences has received much attention in recent years. One domain where far transfer effects have frequently been reported is music education, with ...

Abstract Clustering algorithms have been successfully applied in analyzing building energy consumption data. It has proven to be an effective technique to identify representative energy consumption patterns as well as being a pre-processing step for other techniques. In this paper, we propose a clustering method based on k-shape algorithm, which is a relatively novel method to identify shape patterns in time-series data. In the experiment, clustering is performed for each individual building according to its hourly consumption. The novelty of this paper is that a new k-shape algorithm is applied to detect building-energy usage patterns at different levels, and the clustering result is further utilized to improve the accuracy of forecasting models. Ten institutional buildings covering three different typologies are used as case studies and a set of hourly and weekly energy consumption data is further analyzed in this paper. The experimental results reveal that this proposed method can detect building energy usage patterns in different time granularity effectively and also proves that the forecasting accuracy of SVR model is significantly improved by utilizing the results of the proposed clustering method.

The deployment of low exergy concepts in buildings, which promotes high temperature cooling HVAC systems introduces alternative solutions in the tropical climate. This study evaluates the performance of a decentralized dedicated outdoor air system combined with a radiant cooling system (decentralized DOAS-RCS) in terms of occupant thermal comfort and indoor air quality for the tropical context. Different sets of operational scenarios (experiments) have been conducted in the BubbleZERO laboratory to realize the impact of system related parameters like ventilation rate and supply chilled water temperature on thermal comfort and indoor air quality. The results show that supply chilled water temperature and space cooling load have strong impacts respectively on the capacity of decentralized units and cooling panel, which consequently influence indoor air condition. Indoor air was predicted to be in comfort range (−0.2 < PMV < 0.2) only at specific periods of the day and an automatic control was required to modulate the system under various indoor and outdoor conditions. Main challenges of implementing DDOAS coupled with radiant cooling in the tropics include the condensation risk on the radiant panels, non-uniformity of panel surface temperature and low air movement inside the space.

We present the design, construction and operation of a novel building systems laboratory, the BubbleZERO—Zero Emission Research Operation. Our objective was to design a space to evaluate the performance of Swiss-developed low exergy building systems in the tropical climate of Singapore using an integrated design approach. The method we employed for evaluation in the tropics was to design and build a test bed out of the shipping containers that transported the prototype low exergy systems from Switzerland to Singapore. This approach resulted in a novel laboratory environment containing radiant cooling panels and decentralized air supply, along with a self-shading, inflated “bubble” skin, experimental low emissivity (LowE) glazing, LED lighting, wireless sensors and distributed control. The laboratory evaluates and demonstrates for the first time in Singapore an integrated high-temperature cooling system with separate demand-controlled ventilation adapted for the tropics. It is a functional lab testing system in real tropical conditions. As such, the results showing the ability to mitigate the risk of condensation by maintaining a dew point below 18 °C by the separate decentralized ventilation are significant and necessary for potential future implementation in buildings. In addition, the control system provides new proof of concept for distributed wireless sensors and control for reliable automation of the systems. These key results are presented along with the integrated design process and real-life tropical operation of the laboratory.