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Smart controls and thermal comfort

Deliverables

During the course of the SCATs project, thermal comfort data was collected from a number of buildings throughout Europe. 25 buildings were surveyed across the UK, France, Sweden, Greece and Portugal by members of the SCATs consortium. This data formed 3 distinct databases of thermal comfort (transverse, longitudinal and background data) which has potential for further R&D. The data collected included indoor and outdoor temperatures, thermal comfort responses, occupant use of controls, demographic data of building occupants, clothing insulation and metabolic rate. Over 30,000 responses are available for analysis on the databases. The databases will be of use to researchers in the built environment as they contain information on occupant responses to a variety of environmental stimuli, as well as general reactions to their workplaces.
COLT International Ltd. (in conjunction with Oxford Brookes University) have developed a control system for naturally ventilated buildings which incorporates night cooling, solar shading and ventilation, and which is operated using the Adaptive Control Algorithm (see TIP 4). The system has been developed but needs further testing and refinement before it can be marketed. If used correctly, the new system should lead to increased occupant comfort and reduced energy costs.
A new control algorithm, the Adaptive Control Algorithm (ACA), has been developed from databases of thermal comfort responses collected as part of the SCATs project. This algorithm can be used in both naturally ventilated and air-conditioned buildings and if used correctly, should lead to increased occupant comfort and reduced energy costs.
The software produced forms part of the instrumentation developed as part of the SCATs project. The instrumentation itself is described in the result entitled: " Instrumentation for conducting thermal comfort surveys" The role of the software is threefold: - To receive the outputs from the sensors and to convert them to readings on 'virtual instruments' which can form a display on the computer screen. - To perform analyses from the input to calculate measures such as the mean air velocity, or the A-weighted Equivalent Continuous Sound Level (LAeq). - To prompt the user for the completion of a pre-loaded subjective questionnaire4) to upload all the acquired information into a file with a spread-sheet compatible format.
The instrumentation consists of a laptop computer and associated sensors which are physically linked by cables and use the computer program which comprises output 2 for the interpretation and analysis of the incoming measurements. The sensors used in the version of the instrument used in the project measure: the following variables which are converted by the software into readings in the appropriate units: Globe temperature degrees Celsius, Air temperature degrees Celsius, Carbon Dioxide Concentration ppm (mean and standard deviation), Relative Humidity %, Air velocity m/s (mean and standard deviation), Illumination level lux (mean and standard deviation), Noise level (both linear and A-weighted - L10, L90, Leq (mean and standard deviation) dB The instrument allows the physical environment in a particular space to be quickly and accurately monitored in a wide rang of variables. In its present form it is designed to be used by a researcher in conjunction with a subjective survey that can be administered from the same laptop computer. The instrument could also be used as a multi-dimensional data logger. Measurements of no relevance to a particular survey could be omitted or new sensors added to the array as required.