Please read the abstract in the 00front part of this document / Thesis (PhD (Chemistry))--University of Pretoria, 2007. / Chemistry / unrestricted

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The Earth's health is deteriorating and will deteriorate even more rapidly unless people adopt eco-friendly policies. Green building has long been a concept but it has not yet been universally applied in practice. The concept of sustainability emerged in the 1970s and can be associated with the energy crisis and environmental pollution concerns. This research is aimed at investigating whether building “green” is more demanding than non-green buildings in terms of cost and the use of green materials against traditional materials; whether professionals in the construction industry are knowledgeable in terms of green buildings; and lastly, to determine whether green buildings are contributing significantly to the environment. The literature reviewed and results of quantitative research amongst professionals from the Island of Mauritius formed the basis of the study. The study revealed that green building is expensive relative to traditional buildings considering. However, the concepts employed (for example: lower energy use, less waste disposal, lower water usage, and sustainable design) provide green buildings with long term savings. Furthermore, the scarcity of natural materials makes it expensive. The study also showed that contractors and professionals have a preference for traditional materials over green materials thus making them more familiar with traditional materials. Contractors and professionals are believed to understand green materials only on a limited basis. This may be attributed to the specific environmental issues involved; however, the research revealed that the professionals are familiar with the basic concepts of green buildings. Lastly, the research showed that green building is still at its infancy but the benefits of green buildings are understood; resulting in green buildings having a good growth potential. The study should be valuable to construction industry professional and clients.

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This thesis examines the costs and benefits of energy management in office buildings and investigates the relationships between operating costs, space lease contracts, and building value. Energy Management by building owners and managers begins with monitoring and analysing building energy use and continues by reducing energy consumption through operating procedure changes, equipment replacement and control, personnel training, and continued monitoring. The cost to complete energy management projects in 12 office buildings is analysed. The average, before tax, internal rate of return for the 12 energy management programs was 22.1%, on total expenditures of roughly $1,200,000. Nine of the office buildings are publicly owned and occupied by the provincial government of B.C. The return on the investments in these buildings directly benefits the citizens of B.C. However, in the three privately owned and tenant occupied buildings, the owners have a less direct method of receiving the benefits due to net lease contracts with tenants, under which the tenants pay the energy costs and would normally receive the energy cost savings. If only the energy cost savings in vacant areas acrue to the owner, the after tax returns to the owner from the investments in energy management for the three privately owned buildings are all negative. However, because building value is determined by the net income of a property, and net income is dependent on revenues and operating costs, a statistical analysis of revenues and costs was completed on a 140 building sample of office buildings in the Vancouver, B.C. metropolitan area. The results of that analysis provided support for the hypothesis that energy cost reductions could result in increased lease revenues at the time of lease expiries because tenants are concerned primarily about the total space cost, not the lease payment to the owner. In that case, the returns to the building owners were significantly improved, were all positive, and were as great as 80%. / Business, Sauder School of / Real Estate Division / Graduate

M.Eng. (Engineering Management) / The residential and commercial urban sprawl towards green future is governed by the ability to overcome the challenges facing the high rise buildings sustainability. This research is dedicated to assess the high rise buildings’ energy towards near net-zero energy consumption from the point of view of production (the on-site energy generation via renewable technologies) and consumption (the usage of low consumption products). The features of the high rise buildings limit the on-site renewable energy production to solar energy, therefore the integration of solar application in the building’s facade plays a major role in the on-site energy production. Since, the relative roof area compared to the height of the high rise buildings is much less than the single family houses. Therefore, the use of the facade in high rise buildings for clean energy production becomes a major element towards its sustainability. There are several solar energy production techniques of which the most feasible and effective one is the combined electricity generation and heat collection via integrating PV and thermal collector system this system is denoted as solar Photovoltaic and Thermal (PVT) system. PVT system produces both electricity and heat at a higher efficiency from one integrated system on the same surface area exposed to the sun. For instance, PVT system produces approximately 43% more primary energy than a conventional solar thermal collector per unit surface area, and even around 96% more than a conventional Photovoltaic PV system (PVTwins, n.d). The concept of the PVT system was generated based on the fact that Photovoltaic (PV) system has typically 14-17% efficiency, so the rest of more than 80% is a lost energy; this lost energy goes in a form of heat. This heat could reach as high as 50oC above the ambient temperature resulting in structural damage as well as reducing the system efficiency by 25%. Recovering this harmful heat could reach up to five times thermal energy more than electricity from PV array (Hollick, 2011). From the energy consumption perspective, the air conditioning and ventilation system (HVAC) is considered as one of the highest energy consumer in the overall high rise buildings energy consumption (around 40%). This makes it an essential part of any high rise buildings energy solution therefore several low energy consumption HVAC systems has been developed recently. As such, absorption chiller presents one of the greenest HVAC system whereby it has no moving part, no electricity required, thermal driven system (use heat to produce cold) and could be operated by solar thermal energy. In this sense, the enterprise should respond to the increasing demand of the high efficiency buildings mainly by developing new solutions that enhance the latest green technologies and overcome the recent energy challenges.

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A Toy Model of an artificial chemistry that treats molecules as graphs was implemented based on a simple Extended Hückel Theory method. Here we describe an extension of the model that models chemical reactions as the result of “collisions”. In order to avoid a possible bias arising from prescribed generic reaction mechanisms, the reactions are simulated in a way that treats the formation and breakage of individual chemical bonds as elementary operations.

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