Highly glazed facades of commercial buildings are desirable from the point of view of architects, building owners, and building occupants because they create visual connections with the outdoors, offer the possibility for a naturally-lit workplace, and satisfy certain aesthetic desires. The physical properties of glass, however—even when part of the best current window systems—means that this form of environmental separation is highly vulnerable to thermal flux from and to the outdoor environment. The transmission of solar radiation to the perimeter spaces represents an important source of thermal influx, and is typically controlled with shading devices. At best, shading devices create a secondary thermal barrier between indoor and outdoor environments, which can lower energy consumption, decrease peak load, allow for smaller HVAC systems, and provide better occupant comfort. The physical influence of indoor blinds, though, is not always so straightforward. They tend to create two primary effects that operate in opposing directions in regards to energy consumption: (1) they reflect a portion of shortwave solar radiation entering the building back to the outdoors, and (2) they significantly increase the window surface area available for convective heat transfer, which can increase the convective fraction of solar gain, and potentially increase the magnitude of the instantaneous cooling load. For these reasons, the overall impact of interior blinds on equipment load and energy consumption is difficult to foresee. This study describes the results of experiments that tested various configurations of blinds in an outdoor test chamber that simulates conditions in a highly-glazed commercial office building. A simulation model that gives good agreement with experimental results was simultaneously developed. This model will allow retroactive parametric testing of blind parameters for the same given weather and internal load conditions. / text

Prompted by the energy crisis in the 1970's, European level fiscal and financial measures encourage energy efficient building design. "Mixed mode" strategies can be employed in buildings with moderate thermal loads, this approach can reduce building energy usage, and by inference, reduce C02 emissions. A mixed mode approach might employ chilled surfaces with displacement ventilation. This thesis investigates the performance and integration of one form of chilled surface design, (a sub-dew point chilled beam), within mixed mode strategies. Sub-dew point chilled beams have a surface temperature that is at or below the zone saturation temperature, this increases the cooling capacity of the chilled beam and consequently produces a latent heat transfer addition due to condensation mass transfer. This thesis describes the sensible and latent modelling approach which models the zone, sub-dew point chilled beam and mixed mode strategy thermal plant response to external disturbances. The thesis describes the use of an Enclosure Comfort Performance Indicator that acts as the objective function for the optimization of the mixed mode strategies with and without the integration of the sub-dew point chilled beam. The implementation of the Complex method for finding the operational optimums of the mixed mode strategy is described, and its effectiveness at finding the optimum solution evaluated. Normalised energy, cost and comfort performance indicators are used to assess the overall performance and integration of the sub-dew point chilled beam for different mixed mode strategies, for the ambient test conditions and for different thermal weights of building construction.

Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references.

No description available.

Published Article / The paper presents a critique of passive and active thermal comfort strategies. Extensive review of literature on passive thermal comfort energy efficiency interventions and their benefits was under taken. The paper explains the correlation between climatic comfort and energy efficiency. The applicability of the energy management process in ensuring energy efficiency is presented. Passive thermal comfort energy efficiency interventions have been seen to provide thermal comfort as well as energy efficiency. Their major shortcoming is their disability to work in all kinds of weather, heating in the winter and cooling in the summer. There is need to optimize passive thermal comfort energy efficiency interventions so that they provide heating in the winter and cooling in the summer.

Thesis (PhD)-Open University. BLDSC no.DX180440.

The target for carbon dioxide (CO2) emissions reduction in the UK is set at 20% by 2020 and 80% by 2050. The UK housing stock is one of the least energy efficient in Europe. The energy used in homes accounts for more than a quarter of energy use and carbon dioxide emissions in Great Britain. Therefore, it is imperative to improve the energy performance of the existing housing stock and fully exploit energy efficiency and renewable energy interventions. Several tools have been developed particularly in the last decade for energy assessment of dwellings, largely to inform policy development. However, when it comes to policy implementation stages, stakeholders such as local councils, energy suppliers, social housing providers and planners lack an effective tool, which assists them in estimating the potential for energy performance improvement through implementation of energy efficiency and renewable energy interventions. The UK government has several policies and initiatives to improve the energy performance of the housing stock. This research discusses the development of framework and a prototype tool to assist in implementation of these policies. There are a number of databases that hold information about the condition of the housing stock. This is in the form of digital maps, aerial and terrestrial imagery and statistics from census and housing surveys. This research presents an innovative way of integrating this information to undertake energy performance assessment on various geographical levels. The framework and the prototype allow stakeholders to determine the baseline energy performance of the dwellings based on their existing characteristics. This information is then used to estimate the potential for reduction in energy consumption and CO2 emissions and associated costs. Also integrated within the framework and the prototype is analytical hierarchy process based multi-criteria decision analysis technique that supports stakeholders in selection of energy performance improvement interventions suited to their requirements. Energy Performance Improvement of Dwellings Abstract Amit Mhalas, 2013 iv The developed framework and prototype are calibrated and validated with empirical data to determine the accuracy, reliability and trustworthiness. To demonstrate the practical applicability of the framework and the prototype, two separate case studies are undertaken involving the stakeholders. The results from the case studies indicate a potential to reduce CO2 emissions from dwellings by 70% through installation of energy performance improvement interventions. The developed framework and the prototype are expected to assist stakeholders in making informed decisions with regard to the implementation of energy policies and initiatives and contribute to meeting CO2 emission reduction targets.

Thesis (Ph. D.)--Open University. BLDSC no. DX204584.

Thesis (M. Sc.)--University of Hong Kong, 1995. / Includes bibliographical references.

Thesis (M. Sc.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 71-74).