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The post-installation verification of wind turbine performance is an essential part of a wind energy project. Data collected from meteorological instruments and from the turbine is analysed to produce an estimate of the annual energy production (AEP) which is compared against expectations. However, turbine warranties can impose very strict data filtering criteria which can lead to high rates of data loss. As a consequence, measurement campaigns may last longer than expected and incur additional costs for the development. This project aims to investigate the extent of the problem and the potential of alternative data filtering strategies with respect to data loss, AEP estimates and the dispersion of points in the power curve scatter plot. In doing so, it targets a wide range of meteorological parameters with theoretical relationships to wind turbine power production with particularinterest in those not accounted for in the current standard. The identification of viable filtering strategies with lower data loss would provide significant benefits to wind energy development projects in terms of greater control over timescales and reduced costs. Data from a sample of power performance tests is analysed to explore the range and severity of the problem of data loss. It confirms the wide variation in warranty conditions, demonstrates the extent and likelihood of data losses and quantifies the financial implications within the limits of commercial sensitivity. When indirect costs are taken into consideration, the impact of extended measurement campaigns can theoretically reach tens of millions of pounds. A new, high-fidelity dataset is then compiled so that the effects of alternative filtering strategies can be examined. The dataset covers the whole of 2017 and consists of over 700 parameters of which 74 are selected for investigation here. The eFAST method of global sensitivity analysis is used in combination with correlation analysis to reduce this number to11 parameters which are then used to define alternative filtering criteria. Similar AEP estimates are obtained by application of conventional and experimental criteria to the research dataset. In the case of the experimental filters, however, the data loss was 11% compared to 63% data loss with conventional filters. Conventional filters were also shown to increase the dispersion in the power curve scatter plot by over 10%, while dispersion did not increase significantly with the experimental filters.

This study has been undertaken to research the impact of shading on a large scale solar PV site at 56° latitude north, this is the first site in the UK at this latitude, consisting of 2500 solar panels across a 5 acres. As solar altitude decreases obstacles and blockages become more of a hindrance and careful planning is required to ensure the amount of shading on the panel surface is kept to a minimum. The impacts of shading on the Edinburgh College Solar Meadow, from obstacles along the Southern and Eastern edges have been investigated. The accuracy and applicability of existing methods of solar resource modelling and solar photovoltaic (PV) module performance are investigated in the case of the ground array installation. The principal derived quantities consist of slope irradiation, cell temperature and cell efficiency. Experimental data was collected on site through both automated and manual measurements for comparison with the calculated quantities for both triangulation and quality assurance. The impact of shading has been analysed and the effect on energy delivery captured throughout the year. The research undertook detailed modelling in order to compare and evaluate the data obtained with further comparisons made between a number of modelling tools and other forms of output associated with the solar farm directly. The site was expected to generate 560,000 kWh across the year with no impact from shading, based on the installers assumptions. Results indicate that the models used to compare and contrast slope irradiation, cell temperature and cell efficiency are accurate and within the expected range as per manufacturer specifications. The results also show that shading impacts the energy generation with a significant reduction in the winter months with respect to the available energy at the site by as much as 50%. Being the first study of its kind, at high latitude in the UK, to show the importance of accurate shade modelling at higher latitudes the findings show greater consideration is required at concept stages when taking account of solar obstacles. Shading has reduced the overall output, of this particular array, by 136,859 kWh across the year studied.

Climate change is a significant issue in today's society as countries work towards decarbonising the economic sectors that contribute to significant greenhouse gas emissions. The electric vehicle (EV) is proposed as a solution to reduce the level of emissions in the transport sector. However, if an EV is powered by an electrical fossil fuelled source, their penetration into the UK market will have minimal mitigating effects, as emissions will simply shift from the transport sector to the energy production sector. Limited research has evaluated the loss of propulsion energy as a result of operating on-board climate control systems, and has focused more on traction energy. Unlike conventional fossil fuelled vehicles, EVs do not produce waste heat to warm the interior space of the vehicle. The present research found that up to 30% of a vehicle's total energy consumed per trip is allocated to heating requirements, thus the present research developed a temperature predicting numerical algorithm to compute indoor cabin temperatures. The vehicle was exposed to ambient climate conditions with an auxiliary heating or cooling system to evaluate this thermal model. The numerical algorithm could predict the temperature of a cabin space under solar space heating conditions with 62% more accuracy than previously developed models when comparing the Root Mean Square Error performance indicator. The presently developed temperature prediction algorithm may be applied to a route planning application, thus indicating the electrical energy required by the vehicle's battery for users to increase or decrease the desired temperature level. Additionally, this study investigated the ability of a renewable energy resource to decarbonise the vehicle's built-in climate control system. Integrating solar panels on the roof and bonnet of an EV to power an auxiliary climate control system reduced the electrical loading required to reach the occupant's thermal comfort. By installing an auxiliary heating system to increase cabin temperature by 2 or 5°C, the present research found that energy consumption of the built-in climate control system was reduced by 22% or 57%, respectively. This illuminates the potential an auxiliary climate control system has in improving the thermal performance of EVs.

The total incident irradiation on a surface such as a photovoltaic (PV) module is the sum of beam, sky-diffuse and ground reflected radiation. Ground albedo or ground reflectance is defined as the ratio between the ground reflected radiation and the global incident radiation. A constant albedo value of 0.2 for bare ground and 0.5 for dry tropical localities is widely accepted and is used in the modelling of PV systems. The real albedo values of foreground surfaces are different and hence using a constant value may be unsuitable to accurately predict the output of PV systems. This research investigated the real albedo values of various foreground surfaces and how it is affected by the factors such as ageing, solar altitude, rain and cloud cover (sky conditions). To investigate the impact of such factors, an experiment was setup to measure the albedo of conventional foreground materials (grass, sand and cement) and non-conventional materials (white pebbles, white paint, white tiles and aluminium foil). These materials were selected based on the type of PV applications such as solar farms and Building Applied Photovoltaic. The measured average albedo values of grass, sand, cement, white pebbles, white paint, white tiles and aluminium foil were 0.20, 0.36, 0.56, 0.15, 0.70, 0.61 and 0.73 respectively. Research has shown that non-conventional materials, increased the slope irradiation and ultimately the energy generation of PV modules. These results were further validated using the long-term data from the Garston and Edinburgh database. Lastly, a new computational tool was developed, which considers various albedo values of foreground materials simultaneously for any tilt angle of a PV module to compute the ground-reflected component.

Can Battery Electric Vehicles replace conventional internal combustion engine vehicles for commuting purposes when exposed to a busy corporate activity within the city of Edinburgh? This thesis investigates the application of Battery Electric Vehicles (BEV) use in a commercial business environment in the city of Edinburgh, Scotland UK. The motivation behind this work is to determine if the Battery Electric Vehicle can replace conventional fossil fuel vehicles under real world drive cycles and the desire by many to combat the causes of climate change. Due to the nature of this work a significant part of the work will be underpinned by the quantitative methodology approach to the research. As the question indicates the research is supported by real live data coming from the vehicle both in proprietary data logging as well as reading and analysing the data coming from the vehicles own Electronic Control Unit (ECU).There will be mixed research methodology encompassing quantitative and qualitative research to obtain a complete response in respect to the management of the vehicle these methodologies will be the analysis of the measurable data as well as explorative, to gain the underlying reasons and motivations for choosing a battery electric vehicle as an option to the conventional vehicle for this type of application use.

Cement production requires intensive use of natural raw materials and energy. It also results in emissions to the atmosphere, the most significant being COZ. Studies estimate that the cement industry is responsible for 5% of global man-made COZ emissions. Managing and reducing these emissions is therefore a key priority. Cement emissions come from the following sources: chemical clinker-making process (50%-60 %), combustion of fossil fuels (40%), and indirect emissions from purchased electrical power (5%). This research has been carried out with the main objective of assessing the environmental impact of cement production and the potential for reducing its CO2 emissions. To achieve this objective, the performances of three cement companies were investigated and specific indicators set to measure the development of each company and benchmark the performances against each other. The research takes into account social, economic and environmental factors. The assessment used in this study is based on the WBCSD initiatives and its sustainability approach to cement production. This assessment has been conducted by indicating the best performance cement company and displaying the weak points of each of the benchmarked companies. This benchmark was used not only to estimate the environmental impact of cement operations and production among best performance companies, but also to determine new opportunities for efficient cement production, energy efficiency consumption, and low COZ emissions. This study used the benchmark to analyse the Lafarge, Holcim, and Taiheiyo cement companies. The research investigation is based on the review and analyses of data collected during authorised visits to the operating sites of each of these cement companies. Further required data was obtained from the companies' Sustainable Development Reports. A procedure for developing comparable environmental performance indicators, useful for benchmarking, has been described. This procedure has been used to develop key Environmental Performance Indicators, also taking into account economic and social .performance. Both strengths and weaknesses are pointed out in different sections of the case studies. First, the benchmark, the resources to be included and the return figures play a determinant role in the quality of the results. Second, the assessment of environmental performance was evaluated by using specific indicators, including the imperatives indicators to investigate options for reducing COZ emissions throughout the process of manufacturing. The chief original contribution of this research is to identify the opportunities and potential for reducing the CO2 released from cement production, and to develop a model to allow evaluations to be made at different times during the cement manufacturing process of different cement companies, with varying priority levels of selected environmental performance indicators. Recommendations are made to manufacturers and the cement market in order to achieve higher levels of environmental performance (that is, less COZ emissions). This work opens new horizons for further research in this field.

This thesis investigates the feasibility of the use of Low or Zero Carbon Energy Sources (LZCES) in the built environment and the development of an innovative Integrated Renewable Energy Planner (IREP) tool. It can be divided into four main research areas; an investigation into the on-site renewable energy resource, an analysis in the building energy usage profile, a development of a decision-making tool for the rapid identification of the most appropriate LZCES option and a post occupancy monitoring and modelling of a building. This research work details the following considerations of LZCES: passive solar space heating modelling (PSSH); performance of building integrated including solar water collector (SWH); solar photovoltaic (SPV); wind technology (WT); ground source heat pump (GSHP); tri-generation (TriG); biomass (BioH) and rainwater harvesting (RWH). Recorded Chartered Institute of Building Services Engineer (CIBSE) data from fourteen cities around the UK were used to assess the wind, solar electric, solar passive thermal, solar water thermal, ground source and rain resource. As part of this project, an unoccupied solar house was monitored for one summer and one winter month in East Whitburn, Scotland. A detailed investigation into the effect of external temperature, irradiance and thermal mass was conducted on building perFormance and indoor temperature. It was found that the estimated internal temperature simulation was between 2% to 10% different from the monitored temperature. It could be improved if the thermal mass and ventilation rate were estimated more accurately. A collection of manufacturers' data from 10 WTs, 10 SWHs, 3 SPVs, 2 GSHPs, 2 BioHs, 3 Tries and 2 RWHs was carried out in order to test the performance of the IREP tool. Energy, economy and CO2 saving simulations were done on a number of LZCES systems. A final assessment of the number of different options and their impact on the cost, energy and CO2 saving was performed in order to assess the best combination possible. Future development of the IREP tool may aim to assess more accurately the output of each technologies, develop a more user-friendly facade and integrate more technologies such as light pipes, earth duct, solar wall, concentrated solar power, energy storage, UTES, waste-to-energy plant, fuel cells and to extend potentially to recycled materials. Other weather data from rest of the world could make IREP usable for other project scales and countries.

This research is mainly focussed on solar radiation in the UK. It can be divided into four main areas; evaluation of models, analysis of the relations between temperature and solar radiation, critical analysis of the projected future data for the UK and the improvement to the UKCP09 Weather Generator (WG). From the evaluations of models carried out, the Liu-Jordan model performs well for estimating the average hourly global and diffuse radiation. At the individual hourly level however, a number of problems were observed. Regarding clear- sky radiation models, for semi-arid climatic conditions Page model was found to be suitable and for humid climates Yang model is recommended. As for all-sky radiation models, the MRM and Yang model were selected. For the UK, the MRM was found to perform better than the Yang model. Furthermore, a study was carried out to analyse the relationship between temperature and solar radiation. The development of temperature-based mathematical models to obtain mean-daily irradiation was established. A procedure to decompose daily to hourly temperatures was evaluated with respect to world-wide locations and its performance found to be satisfactory. As part of the UKCP09/COPSE project, detailed analysis on the future projected data was carried out to critically evaluate sol-air temperature and the likely change that may occur in the key climatic variables, i.e. temperature, sunshine duration and solar irradiation. Drastic increase of sol-air temperatures and shifting trend of daylight illuminance were found. Furthermore, a sensitivity test was also carried out to analyse the effects of each input variables on sol-air temperature. As a result of the present investigations and communications with the UKCP personnel a new version of WG was released with appropriate modifications. A comparison of the now old- and new WG data sets has been made. Improvements in ratio of diffuse to global radiation and sunshine datasets were found.

This thesis investigates the potential of using wind turbine to offset electricity demand for dwellings or public building. This work involves onshore small and large wind turbine implementation considering the suitability of the location to machine size, starting with wind resource assessment of a candidate site depending on reliable wind data. The present research can be divided into three main parts: modelling and monitoring of small wind turbine performance in built environment using detailed data which was measured on site, measuring longterm hourly data for the design of wind energy systems, and then comparing that annual energy output against four-second and minute by minute data. The third 'part presents a novel statistical tool developed to evaluate relative performance and overall accuracy of wind speed frequency distribution functions. An exploration of the potential for using hourly- as opposed to minute-by-minute data for the utilization of large wind turbines was undertaken as the former set is much more widely available for a larger number of locations within the developing world. It was found that the difference between the annual energy outputs from the latter two data sets was in close agreement with only small differences. The results thus obtained can have significant effect. on the capital cost related to purchase of data, since minute by minute data may be up to 60 times more expensive than hourly data. Actual power curve was experimentally obtained for Zephyr Dolphin micro wind turbine, which was then compared to manufacturer's reported performance; this was done by using four-second data for two complete years. Significant differences were found between the two curves. On-site measured performance of mentioned wind turbine was found to be similar for other reported urban locations. In each case the measured output was only a sixth of the acclaimed output of 2 MWh/annum.Urban wind energy potential for Merchiston site in Edinburgh was investigated. The results are presented in the form of average wind speed, wind roses, and density distribution functions. The effect of sampling interval on wind energy production was also analysed. Finally local spatial variations of wind speed were also studied for the City of Edinburgh.

Energy is undoubtedly the driving force at the core of the development of any nation. There is a direct relation between per capita income and energy consumption. The way this energy is produced, supplied and consumed, affects the local and global environment and is therefore a key issue in sustainable development. The Kingdom of Morocco which is not an oil-producing country is heavily dependent on imported energy to meet its energy demand. Morocco relies on imports for nearly 90 % of its hydrocarbon needs, with the total cost of its imports fluctuating between US$1 billion and US$1.5 billion per year. Electricity supplies are based largely on the combustion of imported coal, which is mainly obtained from South Africa, and imported crude oil from Saudi Arabia, Iran, Iraq and Nigeria, together with electricity imports from Spain and Algeria. This dependence has had an unusually large impact on its economy and environment, affecting foreign exchange, the national debt and government revenues and investment budgets according to the Moroccan Government. In Morocco, the renewable energy sources such as solar energy, wind energy, and biomass are plentiful, widely distributed and environmentally attractive. These resources add no net contributions to the atmospheric carbon dioxide and add no heat to the global environment. Levels of solar insolation exceed 5.00 kWhJm2/day on a horizontal plane in much of the country throughout much of the year, wind resources are favourable for both small scale and wind farm developments in some locations, hydro resources for micro applications are for the most part unexplored but likely to be available in the mountainous regions with good precipitation. Whilst bio-energy reserves are scarce throughout much of the arid and semi arid regions of the country, urban waste is abundant and offers good opportunity for processmg. The objective of this thesis is to investigate the feasibility of renewable energy sources in meeting Morocco's primary energy demand. In this thesis, the energy, electricity, environmental and renewable energy budget for Morocco against the global backdrop is discussed and the related institutional, implementation and policy frameworks including assessment of barriers are analysed. The thesis also addresses renewable energy resource assessment which is a prerequisite to undertake any meaningful exercise to integrate renewable energy technologies into rural energy plan within the overall national energy scenario in Morocco. Furthermore, a comprehensive and scientific model for all important renewable resources such as solar, wind, biomass and micro-hydro throughout the country has been developed, which is a starting point for all future initiatives including private sector participation and market development in this sector. The proposed renewable energy plan could set Morocco on the path to a sustainable energy system with associated economic benefits setting a model for other African and developing countries to follow. The plan clearly contributes to the envisaged purpose of increasing renewable energy contribution in the primary energy balance bringing significant social and environmental benefits into the process. Plentiful wind and solar radiation resources and the proximity to Europe put Morocco in a strong position. Import of technology from and export of electricity to Europe could become a promlSlng strategy to limit the global greenhouse effect and to boost the Moroccan economy.

This thesis deals with- various aspects of broadband horizontal solar irradiance. Quality control of measured datasets are identified and analysed. It was found that solar irradiance datasets may contain significant errors. These sources of errors were divided in two categories, the inherent instrument errors and operation related errors. Methods of assessing the quality of the datasets were evaluated and found to be unsatisfactory. A new method was hence developed to quality control the solar irradiance data. The quality control procedure consists of two tiers of tests. The first tests are physical tests that identify and remove data points that are physical impossibilities. The second tier tests consist of the creation of a mathematical envelope of acceptance in a sky clarity index domain. This envelope of acceptance is based on multiples of standard deviations of the weighted mean of clearness index to diffuse ratio. The available datasets in this study were thus quality controlled to remove any obvious outliers. Modelling the solar resource is an important tool for engineers and scientists. Such models have been developed since the second half of the 20th century. Some models rely on one or two meteorological parameters to estimate the solar irradiance, while other models are more complex and require a far greater number of points. Two of these models have been analysed and evaluated. The two models are all-sky, broadband solar irradiance models. The first model analysed is the Meteorological Radiation Model, or MRM. This model is in fact a sunshine based model, with atmospheric turbidity taken into account as well. The beam irradiance component was found to be acceptable given the number of inputs required by the model. Any extra parameters would increase the complexity of the model, without noticeable improvements. The regressions were modified to take into account sunshine fraction banding. However the diffuse irradiance was identified as one which had the potential III for improvement. Thus, in the present work an attempt has been made to develop improved models. The new model was found to be far superior to the older, original model, thus the name Improved Meteorological Radiation Model, IMRM. The second type of model investigated is the cloud based radiation model. This type of model is simple to use and rely on regressions between irradiation, solar altitude angle and the cloud cover. Careful analysis of the cloud distribution reveals certain flaws in the current regressions. New regressions were formulated and the result was a model superior to all its predecessors. Clear-sky modelling is important for maximum load calculations; however, there is no method of extracting with accuracy clear-sky broadband data. Clear-sky identification techniques were evaluated and a new method was devised. These new datasets were used on four clear-sky models, MRM, Page's Radiation Model, PRM, Yang's radiation model and Gueymard's REST2 model. It was found that using this new method of extracting extremeclear- sky data, the models performed better than when using quasi-clear-sky data. Solar radiation modelling is not an end by-itself, it must serve a purpose for engineers in their applications. Napier University has installed a 160m2 photovoltaic facility in 2003. A 27 -year solar radiation dataset was available for Edinburgh, to do feasibility calculations for the project; however this dataset contained gaps in the data. The cloud radiation model developed in this study was utilised to this end. In addition a complete life cycle analysis was performed on the project, and it was found that with an average efficiency at around 12%, the facility will payback its embodied energy in eight years, and based on a relatively conservative forecast of energy prices, the financial payback is set at under 100 years.

The innovation of natural daylighting light pipe took place more than twenty years ago. Since then its daylighting performance has been reported in a number of studies. To date, however, no mathematical method that includes the effect of straight-run and bends within light pipes has been made available. Therefore, a generalm athematicalm odel for light pipes is desirablet o assessa nd predict its daylighting performance.F urthermore,s uch a generalm odel can enablet he assessmenot f light pipe system's efficiency and potential in energy saving. A modified form of daylight factor, Daylight Penetration Factor (DPF), has been introduced to build a sophisticated model that takes account of the effect of both internal and external environmental factors, and light pipe configuration. Measurementsa nd mathematicalm odelling activities aimed at predicting the daylighting performance of light pipes with various configurations under all weather conditions in the UK were undertaken. A general daylighting performance model, namely DPF model, for light pipes was developed and validated. The model enables estimation of daylight provision of the light pipes with a high degree of accuracy, i. e. R2 values of 0.95 and 0.97 for regression between predicted and measured illuminance were respectively obtained for the above model. The DPF model uses the most routinely measured radiation data, i. e. the global illuminance as input. Considering that in real applications, light pipes installed in a particular building may not receive the full amount of global illuminance as measured by local meteorological office. This may be due to partial shading of the light pipe top collector dome. Therefore, to enable the application of the DPF model in practical exercisesf undamentalw ork on sky diffuse illuminance measurementsh ave been undertaken. An exhaustive validation has been carried out to examine the DPF model in terms of the structure of the model and its performance. The DPF model was compared against studies by other independent researchersin the field. Independentd ata setsg atheredf rom a separates ite were used to validate the performance of the DPF model. Comprehensive statistical methods have been applied during the course of validation. Relevant, brief economic and environmental impact of the technology under discussion has also been undertaken. One of the main achievementso f this work is the mathematicalm ethod developedt o evaluatet he daylighting performance of light pipes. T'he other main achievement of this work is the development and validation of the DPF models for predicting light pipes' daylighting performance.

In 1987 the World Commission on Environment and Development proposed a reduction in per capita energy consumption of 50%. Increasing demands, and initiatives of this nature, produce a need for more reliable assessment methods, measurement tools and improvement regimes. Since the late 1960's Life Cycle Assessment (LCA) has become an increasingly important tool for engineers, technologists, scientists, designers, managers and environmentalists alike. LCA enables the effects which products, processes and activities have on local, regional or global environments to be assessed, adopting a holistic, or whole life approach to design methodologies. The design of window systems has a large impact upon LCA results generated. Thermal performance properties influence energy consumption patterns throughout a lifetime of use, while appropriate use of materials, window positioning and size have a knock-on effect on lighting control functions and air conditioning demands. In developing countries, residential sectors account for between 20% and 30% of the total energy used (30% in the UK). Windows in dwellings alone account for 6% of the total UK energy consumption. This thesis addresses an ongoing need to focus on sustainable development, using LCA as an assessment tool to develop a greater understanding of the window life cycle, and to highlight improvements which are necessary to lessen its environmental impact and make the processes involved more benign. To do this successfully requires that the demands of modern day living, and the comfort conditions expected, be incorporated into design criteria, whilst ensuring that the needs of future generations are not compromised by today's activities. Along with rising demands to improve efficiency and decrease energy consumption in buildings, comes an expectation for continual improvement in building interiors. To this end, both the aural and visual haracteristics of window installations become paramount, in addition to the well researched thermal performance criteria. Much research has focused on investigating the social and physiological benefits associated with improved interior environments. The correlation between worker satisfaction and performance has been well proven. If complete physical well-being is satisfied then an individual's mental well-being is less likely to be affected by the additional stressors of environmental dissatisfaction. An optimisation model has been developed, linking the thermal, aural and visual performance of varying window designs, such that an "advanced" window system is created. Two outputs are generated from the model, which may be used to evaluate the "optimum" window design in terms of energy consumption and global environmental impact. Optimisation of energy consumption incorporates embodied energy, thermal performance and electric lighting demand, over the life cycle of a window. Global environmental impact optimisation is similar, but evaluation is based on energy generation, and greenhouse gas production. Finally, a flowchart for optimisation guides the user towards a glazing solution which offers sufficient noise attenuation, whilst minimising thermal losses and electric lighting demand. Each output provides a guide for design, leaving room for judgement, and is not intended to be followed definitively. Recommendations for improvements to manufacture systems and production of multiglazed windows are offered, based on sustainable development criteria. Future research needs, which are necessary to minimise the total environmental impact resulting from multi-glazed window production, are also discussed.

This thesis highlights the benefits to occupants and owners of buildings who utilise daylight effectively. Many cases of absence are related to depression or Seasonal Adjustment Disorder(SAD) which results from inadequate exposure to daylight in the work place. The use of artificial lights has been linked to minor as well as more serious ailments such as cancer and increases in cases of miscarriage. The use of daylight in buildings from economic and environmental perspectives is the main concern of the thesis. The work and analysis of this thesis have produced two new illuminance models. In addition detailed illuminance and irradiance data for Central Scotland were recorded which has previously not been available. A comprehensive study of luminous efficacy research was undertaken in Chapter 3 which evaluated a complete range of models. Furthermore the luminous efficacy of various UK and international sites were compared to examine climatic differences. The development of a new slope illuminance model which more accurately predicts external illuminance for all sky conditions was shown to perform consistently better than previous models. This was due to the new model's treatment of the sky background diffuse component utilising an anisotropic form as opposed to the traditional assumption of an isotropic sky background diffuse component. The availability of sky luminance distribution data from introduction of sky scanners enabled innovative daylight illuminance factors to be developed. These factors model the distribution of the sky's hemisphere under all levels of cloud cover and calculate the internal illuminance taking into account window size, glazing type, orientation and time of the day. The development of the daylight illuminance factors has been shown to significantly improve the energy efficient design of buildings in comparison to the current practice of employing the sky factor method. The daylight illuminance factors were used in a modelled building design scenario to assess their performance and to examine energy efficient design. Lighting controls and various glazing types were analysed to study their impact on a buildings energy consumption. This study also incorporated an embodied energy analysis which considered the energy consumption of windows in manufacture and operation.