Research Summaries

Research within ESRU is concerned with the evolution of simulation tools to assist designers in their efforts to improve the energy/environmental performance of buildings and the related technologies to harness renewable energy sources.

Research goals include improving the accuracy of the mathematical models and numerical methods used to represent heat, mass and power flow; applying simulation to optimise energy component/system performance and promote energy efficiency measures; evolving software engineering techniques that increase researcher efficiency and program robustness; improving confidence in predictions through the development of program validation, calibration and accreditation procedures; and constructing knowledge-based design support environments to enable application interoperability and effective team working.

Dissemination goals include establishing simulation as a core teaching technology within under- and postgraduate courses; extending, through consultancy and open source licensing arrangements, the power of simulation to the design profession; and fostering the uptake of computer-based methods through training activities.

The following brief descriptions relate to completed and ongoing research projects areas with more complete descriptions cited where appropriate.

Select a topic:

Building Market Transformation | Noise Surveys | Daylight utilisation | Hybrid photovoltaics | Advanced glazing
Embedded generation | Mould growth | Energy monitoring & targeting
Computational fluid dynamics | Integrated simulation | Web-based learning
Intelligent interfaces | Performance appraisal | Program validation
Ducted wind turbines | Hydro, wave and tidal power | Clean combustion
Modelling uncertainty | Control systems | Power flow modelling
HVAC primitive parts | Indoor air quality | Product modelling
The Lighthouse building | Internet energy services | Smart Homes | Energy efficiency

PhD Projects (Past and Present)


Building Market Transformation

The Building Market Transformation (BMT) project was a subset of the UK Carbon Trust's Carbon Visions project (2005 – 2009), which aimed to provide research to support a 60% reduction in carbon emissions from the building sector by 2050. ESRU supported the following areas as part of this project: Scottish policy formulation , Domestic buildings carbon performance and upgrade strategy , Non domestic building performance and upgrade strategy , Impact of occupant behavior and the future use of air-conditioning.

Scottish policy formulation

ESRU represented the BMT project on a number of expert panels in Scotland. Outputs include: the Scottish Government's ‘A Low Carbon Building Standards Strategy for Scotland’ [1], the WWF ‘Carbon Countdown for homes: How to make Scotland’s existing homes low carbon’ [2], and a presentation to Scottish Building Standards on ‘Air-tightness and Ventilation’ [3]. A 2-day seminar was held for Government, industry and local authorities on strategies for low carbon buildings which focused on ‘Achieving A-rated Buildings’ [4].

Domestic buildings carbon performance and upgrade strategy

ESRU reviewed the standards for advanced housing and explained divergences through the use of dynamic simulation [5] . The appropriate specification of thermal mass, ventilation and shading [6, 7] through the use of simulation in design was demonstrated to be important for the maintenance of comfortable summer temperatures and the avoidance of air-conditioning.

ESRU developed the simulation-based EDEM tool [8, 9, 10, 11] for building upgrade policy and strategy formulation in parallel with the BMT UKDCM2 stock model. The EDEM model was used to provide an independent review of the UKDCM2 generated scenarios for 2050 and additional insights [12] such as EPC ratings and financial information. The analysis included the sensitivity of carbon and cost performance to grid carbon intensity, system performance, system costs and generated electricity feed-in tariffs. EDEM was also used to provide case studies of individual dwellings and housing stocks [13]. The EDEM analysis confirmed the technical feasibility of the BMT 2050 scenarios. The required upgrade measures were projected to be economic where applied to older unimproved dwellings but marginal or uneconomic where applied to average or better than average dwellings. An issue was highlighted with the fixed carbon emissions factor used in the EPC implementation. The EDEM tool output together with the UKDCM2 outputs can be used to inform future policy.

Non domestic building performance and upgrade strategy

ESRU investigated the BMT non-domestic model and scenarios using the UK Government's NCM methodologies, SBEM and dynamic simulation. Research was carried out to establish current typical, current best practice, and future potential performance levels, for a range of technology options [14], which could be applied to new non domestic buildings or to upgrades. The different technology options were evaluated using SBEM for a range of buildings and some optima established [4]. Limitations of the regulatory methods were explored and issues highlighted.

Impact of occupant behavior and the future use of air-conditioning

ESRU has been incorporating algorithms representing occupant comfort and behavior in dynamic simulation and using these to assess the impact on energy and carbon [15, 16, 17, 18]. These algorithms have been provided to the Tarbase team and used in its analysis under the Carbon Visions Project (Tarbase is a parallel sub-project to BMT).

ESRU analysed the current UK building regulations and EPC calculations relating to naturally ventilated, mechanically ventilated and air conditioned buildings [19] and concluded that there was a probability that air-conditioning would be adopted in future due to either poor performance in practice or over-specification in design. A methodology for robust design and use of buildings has been proposed that would reduce the need for mechanical cooling [20].

Related publications, reports and presentations

[1] 'A Low Carbon Building Standards Strategy for Scotland', Scottish Government Report, ISBN: 978-1-904320-06-7, 2007.

[2] 'Carbon Countdown for homes: How to make Scotland’s existing homes low carbon', WWF Report, 2008.

[3] Presentation to Scottish Building Standards, 'Air-tightness and Ventilation', March 2008.

[4] Seminar: 'How to achieve A-rated buildings', SESG, Glasgow, June 2008.

[5] 'Sustainable Housing: the impact of thermal mass, ventilation and insulation for a range of climates and occupancy scenarios', Proc. Building Simulation '05, Montreal 2005.

[6] 'Sustainable Housing Standards, Presentation', Presentation toNCEUB, Glasgow, 2005.

[7] 'Sustainable Housing: the use of simulation in design', Proc. Eurosun, Glasgow 2006.

[8] EDEM url

[9] 'Energy and Carbon Performance of Housing: Upgrade Analysis, Energy Labelling and National Policy Development', Proc. 28th AIVC Conference, Crete, 2007.

[10] 'The EDEM methodology for housing upgrade analysis, carbon and energy labelling and national policy development', Proc. eSIM2008, Quebec, Canada.

[11] 'Energy and Carbon Performance of Building Stocks: Upgrade Analysis, Energy Labelling and National Policy Development', J. ABER, Accepted for publication in 2009.

[12] '2050 Domestic Scenario Review', Proposed submission to E+B, BRI or E Policy by end 2008.

[13] 'Carbon and Energy Performance of Housing: A toolset for policy development applied to a local authority housing stock', Proc. Eurosun, Glasgow 2006.

[14] '2050 Non domestic Scenario Review, Sumbission to E+B, BRI or E Policy by end 2008.

[15] 'Using results from field surveys to predict the effect of open windows on thermal comfort and energy used in buildings', Energy and Buildings, 39 (7) 823-836, 2007

[16] 'Development of an adaptive window-opening algorithm to predict the thermal comfort, energy use and overheating in buildings', J. Building Performance Simulation, 2007.

[17] 'Occupant behavior in naturally ventilated and hybrid buildings', Proc. ASHRAE Winter Session, January 2009.

[18] 'Dynamic simulation: potential role of adaptive comfort and occupant behavior in building design and regulations', Presentation to NCEUB, UCL, April 2007.

[19] 'Air-conditioning: The impact of UK regulations, the risks of un-necessary air-conditioning and a capability index for non-air conditioned naturally ventilated buildings', Proc. NCEUB, Windsor Conference, 2008.

[20] 'The future impact of air-conditioning: a methodology for robust buildings', Submitted to BRI for publication in 2009.

[21] 'A Review of Passive Housing in the UK', Submitted to Passive House Conference, Darmstadt, April 2009.

[22] 'Simulation in building design, commissioning and operation: a comparison with the microelectronics industry', Submitted to BS'09, Glasgow, July 2009.

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Daylight utilisation

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Noise Surveys

ESRU have undertaken a number of noise surveys, particularly with regard to monitoring noise levels close to proposed
bulding developments near the M8 motorway.

In one particular survey, in February 2000, noise measurements were undertaken and noise level estimates made for a site adjacent to a raised section of the M8 motorway near Kingston Bridge in Glasgow. As with other ESRU projetcs, the work included analysis of other aspects of the design (in this case a solar access study) Contact: T. Connelly, Elder and Cannon Architects, 40 Berkeley Street, Glasgow

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Hybrid photovoltaics

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Advanced glazing

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Energy efficiency

This project developed a tool to support the development of policy in relation to the options for energy efficiency in the domestic sector. The ESP-r program was employed to determine the performance impact of a range of possible energy efficiency measures and the results were encapsulated within a tool for use by policy makers. For further information on the project and to explore the tool, follow this link.

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Embedded generation

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Mould growth

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Energy monitoring & targeting

 

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Computational fluid dynamics

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Integrated simulation

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Web-based learning

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Intelligent interfaces

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Performance appraisal

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Program validation

ESRU has been involved for over 20 years in program validation, in both national and international projects. The work has included contributions to the development of validation methodologies, including the analytical, inter-model comparison and empirical techniques. The primary focus for the group has been concerned with validating the thermal performance of the ESP-r simulation program, developed within ESRU. Such work is becoming more important as simulation starts to be used more commonly and is being included in international standards. Previous major project involvement on this topic has included contributions within International Energy Agency Tasks 1, 4, 8, 10 and Annex 21, the EC project PASSYS, and studies funded by EPSRC and BRE. Many of the PhD theses that have contributed to ESP-r have also contained a significant validation component. ESRU's current work in this area focuses on developing a comprehensive series of program tests on behalf of CIBSE, and on participating in the recently approved IEA validation study SHC Task 34 / ECBCS Annex 43.

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Ducted wind turbines

ESRU is responsible for part of a large and fully instrumented wind turbine test site some 20 km from Glasgow and owns a number of turbines up to 15 kW rated output. Test work involves students at both undergraduate and postgraduate level, and recent projects have received support from the EC's Thermie programme and from the Department of Trade and Industry.

The following description relates to a prototype ducted wind turbine as designed and fabricated by ESRU for Glasgow City Council as part of a European demonstration project.

Design features

ducted wind turbine with PV spoiler

Principle of operation

The duct is designed to use the pressure differentials created by wind flow over a rectilinear building. The device is located at the edge of the roof, forming part of the parapet. High pressures are experienced on the upwind face of the building, reducing somewhat towards the edges as the air flow accelerates to pass around and over the structure. The duct entrance is shaped to intercept the predominantly upward flow in this region. The angled spoiler (with integrated PV panel) guides the air flow as it curves over the roof, and creates a stable low-pressure region at duct exit, to draw air through the duct and maximise mass flow to the turbine. The turbine rotor is set in the horizontal plane and drives the generator, located beneath the ducting, directly through a vertical shaft. In this way aerodynamic blockage from the generator is avoided and a module of regular shape is produced, which is easy to construct and integrates well with conventional roof parapet profiles. The device is directionally sensitive. At present it will tolerate a 30° misalignment with the wind with minimal loss of power; further improvements in this aspect of performance are anticipated. On a given building, a number of identical modules can be placed in a row. The module can be mounted independently from the roof parapet cladding, so it may be withdrawn for maintenance.

Trial deployment

Seven units have been deployed on the Lighthouse Building in Glasgow and their performance monitored over a one year period commencing October 1999.

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Hydro, wave and tidal power

ESRU has been researching new ways of extract energy from run-of-river and tidal stream sources.

In relation to tidal stream power extraction, a novel Venturi-based device is being researched. The aim of this project is to determine the practical constraints on operation of horizontal-axis marine current turbines. The effects of velocity shear, cavitation and surface waves are being investigated by a combination of tank tests on scale model rotors and computational analysis. The outcome will be an estimate of the operational envelope of such devices, in terms of depth of immersion, range of rotational speeds and physical scale. This will enable more accurate predictions of energy capture by a given machine, and of available energy resources for a particular site.

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Clean combustion

Research into the use of bio-fuels for use in CHP and automotive applications has characterised the fuelling and operation of compression ignition automotive engines under a wide variation of operating conditions. This work has established the calorific value and performance parameters of a range of vegetable and vegetable-ester based diesel fuel substitutes. The performance parameter considered included: the fuel combustion characteristics, the impact on the engine's torque/speed characteristics, the thermo-mechanical stressing, and the resulting exhaust emissions.

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Modelling uncertainty

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Control systems

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Power flow modelling

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HVAC primitive parts

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Indoor air quality

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Product modelling

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The lighthouse building

As the centrepiece of Glasgow's celebrations as UK City of Architecture and Design 1999, the Lighthouse Building designed by Charles Rennie Mackintosh has been refurbished. The project team comprised Glasgow City Council, Page and Park and Oscar Faber. The refurbishment presented the city with an opportunity in relation to an ongoing project being funded by the European Commission and concerned with the use of renewable energy resources in an urban context. A specially configured portion of the building, the observation gallery, served to demonstrate the introduction of renewable energy (RE) systems at the urban scale.

Within the project, the the ESP-r system was used to design a scheme which utilises passive solar features to achieve the lowest practical energy demand and embedded, micro-scale RE based generation systems to match a significant portion of this demand. The technologies chosen for the demonstration included four passive and two active components:

The energy and environmental performance was appraised for the development initially being constructed to current UK best practice (base case), see figure 1.

Figure 1: Gallery overall performance when constructed to UK best practice.

Further appraisals were undertaken to assess the impact the progressive addition that the four passive components would have on the observation gallery's performance when compared to the base case design, see figure 2.

Figure 2: Progressive demand reduction due to the introduction of passive technologies.

The application of advanced glazing resulted in a 59% reduction in heating energy requirements with no discernible impact on daylighting when compared to the proposed building. The passive solar TI facade contributes 46% of the heating energy requirements for the revised configuration. Advanced glazing with integrated luminaire daylight control reduces the lighting energy demands by 80%. Overall it can be seen that the deployment of these passive technologies will bring about a 64% reduction in the annual energy demand. Further simulations were undertaken to determine the optimum location and combination of PV components and ducted wind turbines to match the residual heat and power demands. Figure 3 shows the final performance picture in relation to demand-supply matching and other principal performance parameters such as thermal and visual comfort, gaseous emissions and maximum demands.

Figure 3: Performance after the deployment of passive and active renewable energy technologies.

A combination of 7 DWTs with an installed capacity of 770 W and 11m² of PV components providing 1360 Wpeak proved successful in matching the seasonal energy demands. The DWTs produce electricity predominately during the winter period when the PV components can contribute little. Conversely, the PV components supply power predominately during the summer period when the winds are light. The combination of the two systems gives rise to an embedded RE approach which is well suited to the climate of Glasgow. Compared to the initial design proposed for the observation gallery, the revised construction using complementary passive and active renewable energy technologies results in the energy demands being 31% that of a development constructed to current UK Best Practice .

The electrical supply system within the observation gallery consists of multi-variant, heterogeneous generation systems, DC from the photovoltaics, variable frequency low voltage AC from the ducted wind turbines and a regulated AC supply from the public electricity supply. This results in a combination of supply options being available. These options can be either solely or a combination of the following:

  1. dedicated dc power supply circuits;
  2. isolated ac supply from the renewable energy systems via a battery storage & inverter system;
  3. co-operative ac supply from the electricity supply company and the renewable energy systems.

Option 1 was not favoured because of the increased costs associated with higher current capacity wiring and specialised low voltage appliances. Option 2, although being the most efficient for direct energy utilisation, requires extensive and potentially expensive compliance compatibility to meet the standards set for public electricity supply network connection. Option 3 was chosen as the preferred installation. This enabled the electrical power from the renewable systems to be used for primary power supply to the gallery area, with the battery system allowing the temporal mismatch between supply and demand to be met. The ability to have a back-up charging circuit from the public electricity supply meant that a guarantee of supply was available during an unlikely instance when the renewable energy systems failed to generate sufficient quantities of electricity. The chosen configuration meant that an integrated heterogeneous generation system was configurable with the public electricity supply network without having a direct AC connection. This meant that the electrical supply did not contravene any network connection regulations or have any impact on power quality issues within the public electricity supply network and eliminated costs associated with the various electrical components required for network compliance when making an parallel connection. Figure 4 demonstrates the electrical installation adopted for the gallery development.

Figure 4: Electrical power supply configuration.

The final scheme, as realised and subsequently monitored, is as shown in Figures 5 and 6. See our publications list for further information on the outcomes from this project.

photovoltaic facade

Figure 5: Installation of the PV facade.

ducted wind turbines

Figure 6: Installation of the DWTs.

For more information on the building-integrated renewable energy concept in action follow this link.

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Internet energy services

ESRU has worked within an EC-funced project to develop the SmartHomes, Internet-enabled monitoring and control system suitable for application at the large scale. The system comprises hardware and software components, the latter being fully integrated with the Unit's EnTrak program, which delivers advanced energy management functionality. Together, the SmartHomes and EnTrak systems support a new generation of on-line energy services:


The Linix-based e-box.

The SmartHomes/EnTrak system architecture.

The system comprises an electronic gateway (a Linux-based 'e-box' from Ericsson), sensing/actuating devices, and an e-service centre to store the monitored data (e.g. temperature, humidity, movement, CO, power etc) and process actuation requests (e.g. switching operations). The e-boxes are associated with demand- and supply-side entities (such as buildings and renewable energy components). The sensors are physically connected to the e-box, which returns their outputs to the e-service centre where they may be despatched to service providers who add value. The e-box can also control the actuators on the basis of requests received from these service providers via the e-service centre. This feature allows smart control on the basis of external information. For example, heating systems can be turned as a function of predicted weather conditions, local demand management can be enacted to facilitate a better match with local renewable energy resources, and alarms can be raised in response to local problems (e.g. high CO levels).

Because the communication between the e-box and e-service server must be secure, application protocols such as telnet, HTTP, FTP and SMTP are disallowed; instead, an OSGi encrypted messenger service is employed. The e-service centre utilises a core SQL database from where service-specific data aspect models are extracted and made available to the service providers.

It is envisaged that myriad service providers will exist in future, each offering a distinct service to different end-users such as utilities (automatic meter reading, demand/supply control), home owners (home appliance control, health & safety), local authorities (large scale fuel use management, strategic/tactical analysis), or companies (emissions trading). The downstream service Wed sites are expected to:

To implement such service, the providers may request data aspect models from e-service database server and, in due course, return acturation requests for onward transmission to relevant e-boxes.

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Smart Homes

ESRU co-ordinated an EC funded project called SmartHomes, which commenced in 2001 as part of the EU EESD-Energy Programme (1998-2002), with the primary objective of defining such new energy services and testing them within field trials. Project partners are located in Sweden, Greece, the Czech Republic and the UK. The aim was to prototype and test energy services for citizens and professionals and test cable and wireless approaches to internet connection. The implementations have been based on Ericsson's residential gateway, or `e-box', technology as described above. E-boxes, which are essentially small computers with a Linux operating system, were placed in homes and connected to the Internet and to local sensors/actuators. Sensor data was transferred via the e-box to a service centre from where they are accessed for further processing by designated energy service providers before onward transmission to users. These users, for example utilities, citizens, local authority energy managers and health care providers, then access the information through standard Web browsers, and depending on the particular energy service, may transmit information or control instructions back to the originating homes. The project partners implemented a number of pilot services in their respective countries, focusing on the areas of health and safety, improved energy efficiency, utility load management and consumption metering, large scale energy management and citizen participation. Industrial partners have undertaken market studies and economic evaluations of technology deployment.

Example e-services include:

• real-time monitoring of homes to enable better care for the elderly and other vulnerable groups;
• management of electrical loads as a mechanism to improved the efficiency of supply;
• attainment of a better match between local demands and renewable energy supplies as a means to reinforce power quality of supply in areas where the electricity supply network is fragile;
• development of partnerships between local authority, utilities and telecommunications companies as an apt response to the challenges of an integrated energy market;
• construction of city-scale databases for use in local authority and utility service planning; and
• development of procedures for prioritising home improvements based on detailed consumption data.

To demonstrate the above, the project carried out state-of-the-art and market surveys, developed a prototype system and ran full scale field trials in 4 locations: Sweden (an urban context with extensive existing IT infrastructure), Scotland (a rural context with geographically dispersed homes), Czech Republic (a legacy context comprising eastern block social housing) and Greece (an urban context with weak existing IT infrastructure). In each location, a consortium of technology, utility, local authority and academic partners was established. In addition to running the field trials, these partners provided an economic assessment of the trialed services and provide a marketing focus for further exploitation. Several outputs have arisen that may be disseminated and exploited: information in the form of sate-of-the-art reviews and market studies; know-how, including the experience gained in instrumenting buildings, collecting and analysing data, constructing and operating e-services etc; software, including generic e-box bundles, the analysis pipeline and service delivery components; demonstration services based on the example services developed during the project and hosted on national Web sites; and reference sites.

The e-services that have been demonstrated are:

• monitoring of the indoor temperature in individual apartments;
• information for occupants on the daily cooling demand;
• information to local authorities on energy consumption at the large scale;
• linking of comfort to energy use;
• prediction of regional cooling energy demand;
• remote actuation and control of appliances;
• monitoring of energy consumption in multi-family houses as an aid to equitable billing;
• monitoring of energy use in support of energy management and action planning;
• care for the vulnerable under cold/hot weather conditions;
• monitoring of internal temperatures in cases of fuel poverty; and
• provision of energy consumption data to utilities for local load management.

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PhD & MPhil projects (past and present)

Researcher/ Thesis Title
Project Description
Status

Essam Aasem

Practical Simulation of Buildings and Air Conditioning Systems in the Transient Domain

The thesis is concerned with extending the capabilities of the ESP-r system with respect to HVAC systems simulation.. This involved the development of mathematical models based on the control volume principle to represent components used within HVAC applications. In addition, enhancements and modifications were carried out to ESP-r including improving the plant equation-set solver and allowing for time step control.

The thesis also addressed the issue of incorporating existing and verified modular type mathematical models within ESP-r, such as those developed for use with TRNSYS. The drivers behind this were twofold: to cut down on the time spent redeveloping and validating HVAC component models that already exist and to improve simulation accuracy by using ESP-r's integrated modelling approach to model plant modelling from a sequential to a simultaneous approach.

A comprehensive validation approach was used within the work and case studies presented to illustrate the combined modelling of building plant systems in the transient domain. Finally, the thesis presented some possible future work in plant simulation.

Completed

Alaa Liaq Hashem Al-Mosawi

Thermal Energy Storage for Building Integrated Photovoltaic Components

In the present work, phase change material (PCM) is employed to lower the temperature of a photovoltaic (PV) panel to ensure maximum cell efficiency and protect cells from excessive heat. This hybrid system, termed PV/PCM, allows the stored heat to be recovered using air or water flow. The behaviour of the PCM will be altered by the fact that the thermal properties of specific heat, density and conductivity are continually changing, with new values depending on the context temperature and the phase change temperature range.

The PCM behaviour is represented by a new algorithm, which was constructed, validated, and incorporated within the ESP-r system, with interactions taking place between PV and PCM physical models. Building control strategies were then developed to take advantage of the PCM's latent heat capacity, especially under peak load operation or when high PV temperature is observed. The integration of building control systems with the charging-discharging of the PCM layer enables the program user to control the quality and efficiency of these processes, and allows for the optimal use of the thermal energy stored.

The thesis describes the form of the developed PV/PCM model and presents the results from its empirical validation. Finally, the thesis applies the new model to investigate the impact on building energy efficiency of deploying PV/PCM in practice.

Completed

Ahmad Qatnan Alanezi

Dynamic Coupling of Air Culvert Air Conditioning Hybrid Cooling System in Buildings

This work utilised the ESP-r syste to develop a control strategy for a hybrid cooling system comprising an air culvert and active cooling system The topics studied included:

  • The quantification of the air culvert thermal efficacy.
  • The elaboration of an integrated system design method that accounts for the transient interaction between the air culvert and the air conditioning systems.
  • The requirement for hybrid system control when deployed within different climates.

A ground temperature model was established for a hot/dry climate locationand validated against measured soil temperature profiles. A culvert model was derived and verified empirically and by inter-model comparison. Results showed that the ESP-r model can robustly quantify the thermal performance of an air culvert. The culvert was then coupled to a residential villa situated in a hot/arid climate and its contribution explored. A constant air volume air-conditioning system was then linked to the culvert-building model and used to research approaches to the control of such a hybrid cooling system. A general control strategy was devised corresponding to specific objectives and constraints. Results confirmed that the final control set-up can be implemented for a culvert/HVAC hybrid cooling system regardless of climate type, with cooling load matching in excess of 85% and maintaining indoor temperatures within comfort threshold limits.  

The project concluded is that a culvert may be deployed in a manner that allows significant down-sizing of conventional cooling plant, thereby achieving both capital and running costs savings without appreciable loss of amenity.

Completed

Patrick Ken Amissah

Indoor air quality: linking indoor air humidity with construction moisture transfer.

The objectives of this project are to combine heat and mass transfer (HAM) and computational fluid dynamics (CFD) models in order to support the detailed study of moisture flow as it impacts on indoor air quality and occupant health (through the development of moulds). Specifically, the project aims to improve the modelling of the moisture transfers at the internal surface interface by co-locating the HAM and CFD grids governing the placement of the finite volumes representing the two domains. By conflating the room air and construction domains, it should be possible to predict the time varying temperature/humidity conditions at specific locations and relate these condition to the likely occurrence of mould. Completed
Simon Borg

This thesis addresses microtrigeneration to provide combined heating, cooling and electrical power. By
recycling the waste heat produced from a small energy conversion system and utilising this to run a thermally activated cooling device, such a system has the potential to improve the energy-efficiency of dwellings. An important aspect in evaluating micro-trigeneration is the formulation of a detailed
assessment of its energetic, environmental and economic performance. The research outcomes presented in this thesis makes use of a combined deterministic and sensitivity analysis methodology in conjunction
with data obtained from simulations performed using a whole building simulation tool run at high temporal resolution to model, simulate and assess microtrigeneration performance under varying conditions.

The outcomes include a new method and tool to generate high resolution electrical demand data incorporating the effect of future energy efficiency savings; a dynamic model of an absorption chiller designed to be easy-to-calibrate and detailed, integrated models of a trigeneration system along
with the Maltese apartment building which it serves. Performance simulation of the trigeneration system for the island of Malta indicated that considering the current local electricity grid network, a residentially installed micro-trigeneration system fed by an internal combustion engine and using an absorption chiller as the thermally activated cooling device, would produce primary energy savings of up to 44% along with CO2 savings of approximately 10,000 kg/yr.

Completed

Francesca Born

Aiding Renewable Energy Integration Through Complementary Demand-Supply Matching

Sustainable development is dependent on actions leading to the implementation of energy efficiency measures and the deployment of renewable energy technologies. The purpose of this project was to determine the body f information and analysis techniques required to support the above actions. Matching energy supplies to demand, at whatever scale, required knowledge of the relative magnitudes and temporal characteristics of both profiles. Given sets of demand and supply profiles, optimal combinations can be identified by the similarities in trends and the coincidence of peaks. The match can then be improved by deploying demand management measures, either to reduce the demand or alter the profile. This project examined the above issues and encapsulated the findings within the Merit software tool which is aimed at supporting strategic decisions regarding renewable energy deployment at all scales from grid-integrated to building-integrated. Within the current work models were developed for wind, solar,. electricity storage and diesel generators technologies. The Merit system has been further developed within a related PhD project - see entry under Nicola Smith.

Completed

Ian Beausoleil-Morrison

The Adaptive Coupling of Heat and Air Flow Modelling Within Dynamic Whole-Building Simulation

This project advanced the modelling of indoor air flow and internal surface convection within dynamic whole-building simulation. Computational fluid dynamics (CFD) techniques were conflated with dynamic whole-building simulation, with an accurate treatment of the co-dependencies between these modelling domains. Two flow responsive modelling techniques were devised and implemented within ESP-r. An 'adaptive convection algorithm' enhances ESP-r's thermal simulation domain by dynamically controlling the simulation of internal surface convection. Empirical methods were extracted from the literature and a new method for characterizing mixed flow convective regimes was created to provide the algorithm with a basis of 28 convection coefficient correlations. Collectively these methods can calculate convection coefficients for most flows of practical interest. Working with this suite of correlations, the algorithm assigns appropriate equations to each internal surface and adapts the selection in response to the room's evolving flow regime. An 'adaptive conflation controller' (ACC) manages all interactions between the thermal and CFD modelling domains. The controller incorporates the latest turbulence modelling advancements applicable for room air flow simulation and possesses a suite of handshaking and thermal boundary condition treatments. The job of the controller is to monitor the evolving thermal and air flow conditions in the room and dynamically select an appropriate combination of modelling approaches for the prevailing conditions. The two control schemes implemented to demonstrate the controller make use of a double-pass modelling approach. Each time-step that the thermal domain handshakes with CFD, the ACC performs an investigative simulation to approximate the room's flow and temperature field. Using these estimates, the controller calculates dimensionless groupings to determine the nature of the flow (forced, buoyant, mixed, fully turbulent, weakly turbulent) adjacent to each internal surface. This information is used to select suitable boundary condition treatments for each surface. A second CFD simulation is then performed using the refined modelling approach to more accurately resolve the room's air flow and temperature distribution, and to predict surface convection. In order to protect the thermal domain, a two-stage screening process is used to assess (and where necessary reject) the CFD-predicted surface convection estimates.

Completed

Joe Clarke

Environmental Systems Performance

This project researched the topic of integrated building performance simulation whereby the comfort and health requirements of occupants may be balanced against considerations of energy use and environmental impact. Following on from a review of the possible mathematical modelling approaches, it was concluded that a numerical modelling scheme would be best able to support domain integration and be generally applicable and accurate. A finite volume discretisation scheme was applied to the building system and conservation equations derived to represent the inter-volume energy transfers. A numerical solution method was then developed to solve these equations in terms of dynamically evolving boundary conditions and constraints imposed by imposed control actions. The resulting program, ESP (Environmental Systems Performance), was endowed with a graphical user interface and subjected to applicability and validity trials. These trials confirmed the robustness of the numerical approach. (ESP has subsequently been refined within several EC, EPSRC and PhD projects and is now available under an open source licence). Completed
(paper copy only)

Negrao Cezar

Conflation of computational fluid dynamics and building thermal simulation

The work is a contribution towards the integration of building simulation tools in order
to better represent the complexity of the real world. Advanced fluid flow models (as employed within Building Thermal Simulation (BTS) and Computational Fluid Dynamics (CFD) with different degrees of detail were investigated and their respective modelling deficiencies identified. The CFD technique, which defines the fluid flow on a micro scale,
was integrated into BTS in which fluid flow is described at a larger scale. The resulting combined approach strengthens the modelling potential of each method by overcoming their specific deficiencies. BTS’s inability to predict air flow property gradients within a space was surmounted while the difficulty of estimating CFD's boundary conditions are supplied by BTS. The conflated approach is expected to be employed where gradients of indoor air flow properties can be considered crucial to the evaluation of thermal comfort and energy consumption. A new CFD program, dfs, for the analysis of three-dimensional, turbulent, transient air flow was added to BTS when represented by the ESP-r system. The integration focused on the CFD boundary conditions where the interactions of BTS and CFD take place; these occur at the inside zone surfaces and at zone openings. Three conflation approaches were devised addressing different degrees of complexity and sophistication. The first corresponds to a simple approach where the
BTS and CFD systems exchange information without direct interaction. The second approach consists of three schemes to handle the thermal coupling at internal zone surfaces. The third approach comprises coupling between ESP-r's nodal network approach and the dfs continuity and momentum equations.

The work was validated by analytical , inter-model comparison and empirical means. Three situations, covering the different types of air flows encountered within buildings are discussed to demonstrate the combined method’s applicability when compared with the nodal network approach alone. Finally, conclusions are presented and some possible future work is identified.

Completed

Stephane Citherlet

Towards the holistic simulation of building performance based on an integrated simulation approach.

Preservation of energy resources, occupant comfort and environmental impact limitation are the key issues of modern and sustainable architecture. A multiple-view assessment of building performance at the design stage is therefore essential in order to prevent the delivery of buildings that do not comply with contemporary constraints. This project developed a simulation-based procedure for the life cycle assessment of buildings. The work focused on (1) the design of a holistic building data model, (2) the implementation of this model into the ESP-r system and (3) the application of ESP-r to a case study to assess the thermal, lighting and acoustic performance, the energy consumption and the environmental impact over the building's life span. The work demonstrated the feasibility of a multiple view assessment of building performance based on a single, integrated simulation application. This project was undertaken jointly with the Swiss Federal Institute of Technology, Lausanne.

Completed

Tin-tai Chow

Atomic Modelling in Air-Conditioning Simulation

This project developed a plant component taxonomy for system simulation. From an engineering point of view, many heat and mass transfer processes in air conditioning systems can be unimportant to the overall system performance. Such flow paths were often ignored for the reasons of code simplification and simulation time saving. However, this results in rigid plant models that are difficult to apply to non-standard cases. System simulation software was seen as being inflexibility against the extensive range of problems that might be encountered in practice. Within this project, an analysis of the energy and mass flow paths ocurring within the components of air conditioning systems was performed. A generalised plant database including 27 'primitive parts' was established. This allows a software developer to 'mix and match' models at the flow path level and enabled them to produce component models tailored to the needs of specific problems. The ESP-r system was adapted to include the new plant modelling approach in order to facilitate testing and demonstration of the technique. Completed

Steven Connor

Distributed Dispatching for Embedded Generation

The structure of the electricity industry is currently changing. Interest is shifting away from the traditional large power stations, in favour of distributed generation using large numbers of smaller generators. There are many reasons for this, such as reduced capital cost, easier use of waste heat, and integration of renewable energy. However, it is possible that the means presently used to control and stabilise the electrical grid might not be suitable for distributed generation. This work looks at possible new ways of controlling distributed generators. A novel computer algorithm was developed for automated economic dispatching of small generators. The algorithm is modular in nature and is intended to be used in multiple instances. Simplicity was a major concern to allow for use in low-cost embedded controllers. The algorithm was tested in simulation, and also on an experimental test-bed comprising some small generators (i.e. PV modules, ducted wind turbines), energy storage, and power conversion equipment. Completed

Dru Crawley

Building Performance Simulation: A Tool for Policymaking

Building energy simulation programs have the capability to evaluate a wide range of responses to external stimulus. Typically, software tools are used by practitioners to evaluate individual building designs or retrofits. Other uses for building simulation include overheating prediction, heating and cooling equipment design, evaluation of energy efficiency and renewable energy technologies, and regulatory compliance.

The most powerful use of simulation, however, lies in its ability to look beyond individual buildings to support policy decision-making, including mandatory rule makings such as standards and codes, voluntary financial incentive programs such as those used by utilities to incentivize reduced power demand, evaluating and identifying opportunities for voluntary building energy efficiency programs, or to look at potential impacts related to broader issues such as heat island effects and climate change. Simulation, when coupled with building models that represent a range of building types and locations, can represent a portion of entire building stocks.

This thesis explores how building energy simulation can be used to guide, define, determine, and support decisions by policy makers. Four research studies demonstrate how building performance simulation informs and defines building-related policy for standards, utility incentive programs, energy efficiency programs, and the determination of climatic influence and sensitivity on building perfromance. The studies show how decision-makers can used building performance simulation to craft voluntary and mandatory programs for building energy efficiency. From these studies, a generalized framework of building-related policy research is derived under three categories: research and policy focus, building model, and analysis structure and output data.

Completed
Robert Dannecker So far wind energy does not play a major role in the group of technologies for embedded generation in the built environment. However, the wind flow around conventional tall buildings generates differential pressures, which may cause an enhanced massflow through a building integrated turbine. As a first step, a prototype of a small scale Ducted Wind Turbine has been developed and tested, which seems to be feasible for integration into the leading roof edge of such a building. Here, an experimental and numerical investigation of the flow through building integrated ducting is presented. Pressure and wind speed measurements have been carried out on a wind tunnel model at different angles of incident wind and different duct configurations have been tested. It was confirmed that wind speeds up to 30 % higher than in the approaching free stream may be induced in the duct, and good performance was obtained for angles of incident wind up to 60. The experimental work proceeded in parallel with Computational Fluid Dynamics modelling. The geometry of the system was difficult to represent to the required level of accuracy, and modelling was restricted to a few simple cases, for which the flow field in the building integrated duct was compared with experimental results. Generally good agreement was obtained, indicating that CFD techniques could play a major role in the design process. Predicted power of the proposed device suggests that it will compare favourably with conventional small wind turbines and photovoltaics in an urban environment. Completed
(paper copy only)

Mark Evans

Energy Management in Diverse Estates

 

Completed
(paper copy only)

Arnaud Ete

Hydrogen Systems Modelling, Analysis and Optimisation (MPhil)

This work, undertaken in collaboration with SgurrEnergy, explored computer models to assist engineers in the design and implementation of hydrogen-based energy systems. Four detailed hydrogen system models were estasblished wifor TRNSYS - a stand-alone power system, a low power application, energy buffering for large wind farms and a car filling station - and each was used to explore approaches to design based on technical and economic performance considerations.

To support use in practice, a user- friendly interface was developed for each system model whereby only principal parameters are available for manipulation and simulation results are presented in an integrated manner.

The simulation outputs were validated by theoretical and experimental means and the models were subsequently used to analyse a wind/hydrogen system on the island of Utsira in Norway.

Completed

Jon Hand

Removing Barriers to the Use of Simulation in the Building Design Professions

This work focused on identifying and removing barriers to the use of simulation within the building design process. It employed a case study approach to identify facets of current simulation tools, simulation practice and skills acquisition which were problematic. These observations, made within within research, consulting and teaching contexts, were used as the foundation for several cycles of conjecture and testing. The work produced a Project Manager application, which controls all aspects of modelling building within a simulation-based project. The Project Manager is linked to the data model of the ESP-r simulation engine. It is designed with a tight binding between the user interface and the underlying data model. The data model is expressed asobjects in the user's domain with translations of user actions to data alterations and/or application invocation to perform specific tasks.

The work identified limitations in the procedures used by practitioners to apply simulation within a design project. Successful alternative approaches were developed to better support the value-added aspects of simulation work. The work also identified the considerable power of mentor-based instruction in comparison with traditional or even Web-based learning. Lastly, the work identified the critical place of QA in proving models and ensuring a robust simulation process.

Development of the Project Manager has continued, most notably to support integrated performance modelling of building design problems involving life cycle assessments of energy use, emissions, comfort, indoor air quality, embedded renewables and so on.

Completed

Jan Hensen

On the Thermal Interaction of Building Structure and Heating and Ventilating Systems

This dissertation concerns computer simulation of the thermal interaction between building structure and heating and ventilating system, with the practical objective to ensure thermal comfort while using an optimum amount of fossil fuel. The work focussed on extending ESP-r in the areas of mass flow network based fluid flow modeling features and explicit system simulation. Thermodynamic coupling of fluid flow, plant side energy and mass, and building side energy simulation is achieved with ESP-r's "modular-simultaneous" simulation approach. The dissertation elaborates a multi stage verification and validation methodology, and application of the present work is demonstrated by a number imaginary and real world case studies. Finally, recommendations are made regarding future work in the areas of: theory, user interface, software structure, application, and technology transfer.

Completed

Jun Hong

The Development, Implementation, and Application of a Demand Side Management and Control Algorithm for Integrated Micro-generation within the Built Environment

A demand side management and control (DSM+c) algorithm was developed for use in schemes aiming to embed renewable energy technologies alongside loads within the built environment.
The algorithm convers the two principal demand side measures - load shifting and demand side control. For load shifting, issues such as load flexibility, shifting increment, and shifting boundary and direction were considered. For demand side control, issues such as load priority (i.e. tolerance level), control method and control duration were considered. The impact of possible approaches on the micro environment was considered and ther logic underpinning the adopted algorithms illustrated and demonstrated. To enable an assessment of the impact of the DSM+c algorithm, supply models were developed (e.g. for combined heat and power and heat pumps) and deployed alongside models for time varying electricity-based heating and cooling demand. To support future studies, the DSM+c and supply system models were encapsulated within the Merit demand-supply matching tool.

Completed
Cameron Johnstone

The drive towards reduced energy demand and the deployment of renewable energy technologies has introduced a need for energy systems that effectively integrate energy efficiency measures with passive and active renewable energy devices. In the context of building desing, this project is researching the concept of 'smart facades' whereby the building is able to generate a portion of its required heat and power while reducing the profile of demand for both. The project aims to develop appraisal methods that will enable designers to quantify facade performance and effect comparisons between alternative approaches (such as hybrid PV for heat and power generation, adaptive glazing for daylight utilisation and solar control, and breathable insulation for heat loss reduction and recovery).

Ongoing

Apostolos Karatolios

The Use of Electronic Data Interchange in Energy Management (MPhil)

This thesis deals with the lack of reliable and robust information to support energy management. Specifically, it investigates the use of electronic data interchange to address the problem of data collection and integration. Energy managers are confronted by an astounding array of issues and quantities of data relating to energy and environment issues. The present work addresses approaches to the attainment of a robust and reliable information flow, within and between organisations, to support effective decision-making.
Electronic data interchange techniques for enhancing the integrity and reliability of information flow are developed and tested within two case studies. Finally, the future work required to increase the applicability and accuracy of electronic data interchange is elaborated in terms of the required integration with other aspects of information technology.
Completed

Nick Kelly

Towards a Design Environment for Building-Integrated Energy Systems: the Integration of Electrical Power Flow Modelling with Building Simulation

Building-integrated energy systems providing heat and power (such as photovoltaic facades and small-scale combined heat and power) are becoming a common feature in building design. However, because of the interdependency of thermal and electrical flows within such systems, building simulation tools could not adequately model such systems due to their lack of a power flow modelling capacity. This thesis extended the modelling capabilities of the ESP-r system by integrating an electrical power flow model. An electrical network solver was developed and coupled to ESP-r's existing simulation engine so that the program is now capable of modelling all energy and mass transfers associated with building integrated power systems: heat, power flow, air flow etc. Additionally, thermal/electrical models were developed for fans, pumps, lights, small power loads, a combined heat and power unit and a facade-integrated photovoltaic components. The applicability of the developments were demonstrated through the creation of two example models: a sports centre supplied by a CHP unit and a factory with an integrated photovoltaic facade. Completed

Jae-min Kim

The EnTrak System: Supporting Energy Action Planning Via the Internet.

Recent energy policy is designed to foster better energy efficiency and assist with the deployment of clean energy systems, especially those derived from renewable energy sources. To attain the envisaged targets will require action at all levels and effective collaboration between disparate groups. To support such actions and collaborations, this project is establishing the Internet-enabled EnTrak system for energy and environment information management. The aim is to provide decision-makers with information on energy demands by sector, time, fuel type, and so on, in support of action plan formulation. The requirements of EnTrak are that it can integrate data from a variety of sources (meter readings, field monitoring and modelling for example) and distribute information via the world-wide web. The project is utilising Java technologies to implement the user interface and communication streams. Essentially EnTrak comprises an SQL database and a number of software agents capable of extracting and delivering data aspect model tailored to different user needs.

Completed

Georgios Kokogiannakis

Support for the Integration of Simulation in the European Energy Performance of Buildings Directive

Concerns about the security of energy supply in Europe and the reduction of
greenhouse gas emissions led to the introduction of the European Energy
Performance of Buildings Directive (EBPD). A key requirement within the EPBD is
that Member States will need to adopt a methodology for calculating the integrated
energy performance of buildings. This thesis addresses the use of detailed
energy simulation programs to address the requirements of the EPBD. The research identified the required functionality of these programs to enable them to satisfy both present and likely future requirements of the EPBD.
Completed

Iain Macdonald

Quantifying the Affect of Uncertainty on Building Energy Simulation.

Uncertainty affects all aspects of building simulation: from the development of algorithms, through the implementation of software, to the use of the resulting systems. This work has focused on the problem of quantifying the effect of uncertainty on the predictions made by simulation tools. Two approaches to quantifying this effect were considered: external and inclusive methods. The external method treats the simulation engine as a black box and alters only the input model. Methods within this approach require multiple simulations of systematically altered models and the subsequent analysis of the differences in the predictions in order to draw conclusions on the effect of uncertainty. The inclusive method represents parameters as a function of uncertainty and alters the underlying algorithms of the simulation tool so that uncertainty is included within the computations. Methods within this approach require only a single simulation to quantify the individual and overall effects. To test the applicability of the two methods, they were implemented within the ESP-r system, with the inclusive method applied to ESP-R's core thermal model. It is shown that the results of a single inclusive simulation compare well with the outcomes from the external method. To support the definition of uncertainty at the time of model creation, the uncertainty in key parameters has been quantified. These parameters comprise thermophysical properties, casual heat gains and infiltration rates. Finally, the impact of uncertainty assessment on the design process is explored via three case studies. These examine the use of simulation at the early and detailed design stages and when used to compare design variants.

Completed

John MacQueen

The Modelling and Simulation of Energy Management Control Systems

This work attempts to overcome the inadequacies of contemporary building simulation with respect to environmental control systems modelling. Novel building control systems modelling schemes are devised and integrated within a state-of-the-art simulation environment so that they can be validated and tested in practice. After reviewing existing approaches to control systems design and appraisal, a taxonomy of building control system entities is elaborated comprising logical, temporal and spatial control elements. This taxonomy is subsequently used to identify the models, algorithms, and features of a comprehensive modelling environment. Schemes for improving control model integrity and applicability are presented based upon a simulation approach which treats the building fabric and associated plant systems as an integrated dynamic system. These schemes facilitate the modelling of advanced BEMS control structure and strategies, including:
- hierarchical control from systems level to zone-level;
- single input, single output (SISO) and multiple input, multiple output (MIMO) systems;
- advanced BEMS controller algorithms;
- simulated-assisted control strategies based on advanced simulation time-step control
techniques.

The installation of the developed schemes within the ESP-r system is described and issues related to verification are discussed. Users of control system simulation programs are then categorised and typical applications of the new control modelling features are presented in terms of user types. Finally, the future work required to increase the applicability and accuracy of building control simulation tools is elaborated in terms of the required integration with other technical subsystems and related computer-aided design tools.

Completed + supplement

Amos Madhlopa

Development of an advanced passive solar still
with separate condenser

Clean water is essential for socio-economic development. Nevertheless, in many regiona throughout the world there is limited access to water that meets acceptable levels of quality. This shortage can be addressed through desalination and conventional techniques are available although these require a large input of energy. Consequently, there is need to use sustainable energy sources, with solar energy being the most promising alternatives.

This project developed a solar still modelling method and applied it to design an advanced solar still which was tested subsequently tested outdoors at the
University of Strathclyde and at the Malawi Polytechnic. When compared to a conventional still, the the test results demonstrated that the new still was able to provide more distilled water at lower energy consumption.

Completed
Tom McCombes This thesis is concerned with the ability to model individual and groups of tidal devices
including their mutual interactions. The ability to capture unsteady inflow conditions at
realistic array spacing requires preservation of turbine wakes over a sufficiently large range, at spatial resolutions and over time durations which are not feasible using standard computationalfluid dynamics software. The particular formulation of the NavierStokes equations employed allows the determination of the unsteady pressure and force distributions on a turbine rotor due to the effects of a neighbouring device, even if it is operating some significant distance upstream.

The outcome of this work is a decision support tool which can be used to improve success and reduce risk in tidal power array planning, optimise device configurations and is translatable back into rotorcraft or naval architecture usage.
Completed

Lori McElroy

Embedding Integrated Building Performance Assessment in Design Practice

The work relates to a number of connected initiatives, which over a 20 plus year period assisted design professionals to transfer building energy and environmental simulation technologies from the domain of specialists to routine use in practice. It is written in the context of worldwide concerns relating to climate change, energy profligacy and depleting reserves of finite resources, from fossil fuels to materials, and associated legislative measures relating to the environmental impact of the construction industry.

The research conjectured and tested mechanisms, including performance assessment methods, quality assurance procedures and knowledge transfer, in order to encourage and support the uptake of simulation in design practice and to progress the embedding of the technology as a routine design process activity in Scottish energy sector and construction businesses.

By assisting the uptake of simulation within the professions, the reported work has allowed construction sector businesses to transform existing work practices and in the process to make a significant, measurable contribution to Carbon reduction targets over the last 20 years. Moreover, the work illustrates how the creation of support networks and an integrated, partnership approach between academia and practice can break down barriers to use in practices and increase the effectiveness of the transfer of new technologies resulting in cumulative positive environmental impacts that go significantly beyond the benefits of individual interventions. This conclusion is borne out by independent monitoring of the reported activities.

Completed

Don McLean

The Simulation of Solar Energy Systems

  Completed
(paper copy only)

Christoph Morbitzer

Embedding Building Simulation Programs in Design Practice.

Although detailed modelling tools are available to assist in quantifying energy use and environmental conditions in buildings, in practice they are not used routinely and are most often applied to confirm the performance of a building at the later stages of the design process. By working within an architectural practice, this project aims to: a) identify the barriers to the uptake of the technology; b) define the role of modelling throughout the design process, particularly at the early design stages where the impact on energy and environmental performance is greatest; and c) implement and test modelling procedures within a business setting. Specifically, the project is linking building simulation and CAD and elaborating application procedures for a variety of common design assessment tasks. Completed

Abdullatif Ben-Nakhi

Adaptive Construction Modeling Within Whole Building Dynamic Simulation

The objective of this work was to develop and enhance building environmental performance evaluation tools in terms of adaptive fabric modelling within whole building dynamic simulation. This was achieved by means of adaptive building fabric gridding, facilitating variable thermophysical properties and combined heat and moisture transport simulation. These developments support higher simulation accuracy and, thereby, a better prediction of thermal load and indoor air quality.

The adaptive building fabric gridding technique allows the heat transport through the building fabric to be modelled with variable resolution: for example, some constructions may be modelled using a 1D grid while others are modelled using 2D or 3D meshes. A 1D moisture transport model was then fully integrated with this heat transfer model. Accordingly, thermal bridging through building elements can be represented with high accuracy.

The variable thermophysical properties scheme is able to model the linear,
nonlinear, continuous and discontinuous temperature dependence of thermophysical properties.

Completed
(paper copy only)

Luis Prazeres

Building Performance Data Visualisation

Immense amounts of data are generated by integrated building simulation programs and the translation of data to information that may be acted upon is problematic. Although graphs are an effective way of displaying quantitative information, they are unable to support experiential appraisals whereby the likely performance can be better comprehended. To achieve this requires the use of multimedia techniques, including animation, colour and sound. This project is developing a Web-enabled program, written in Java, to assist in the interpretation of the performance trends inherent in large data sets produced by simulation. The aim is to identify and link key performance concepts and support an inter-comparison of alternative design approaches.

Completed
Gan Kee Seng Economic development within Asia has resulted in a substantial increase in the thermal and electrical power demands of industry, resulting in the construction of new coal-fired power stations. This project, which is sponsored by the Malaysian government, set out to utilise renewable energy technology to satisfy the energy demands associated with the drying of timber for use in high quality furniture manufacture. The work involved the establishment of optimal drying conditions for a range of timber species and moisture contents, and the development of an industrial solar drying unit, which can deliver thermal energy at the grade and quantity required. Finally, the project findings were extrapolated to the climates of other tropical regions of the world. Completed
(paper copy ony)

Nicola Smith

Merit: A Tool for the Matching of New and Renewable Energy Supplies to Demand at Any Scale.

This project aims to develop a simulation tool to allows energy demands for electricity, heat, hot water and transport to be matched with sustainable energy sources. The work builds on the outcomes from a previous PhD project (see entry for Francesca Born) that established the Merit system for demand/supply matching at any scale. Within the present work models of transport fuel demand have been developed, and the range of Merit supply technologies has been extended to include fuel cells, gas & steam turbines, and compression & Stirling engines. The range of fuel types has also been extended to cover bio-gas, hydrogen, bio-diesel, ethanol, methanol, biomass and waste derived fuels, and consideration given to the means of production, including transesterification, anaerobic digestion, fermentation, pyrolysis, gasification, the collection of landfill gas, and the electrolysis of water. The project's outcome, an enhanced version of Merit, will allow the study of the complex relationships that occur when considering the temporal supply and demand of different types of energy, especially where intermittent supplies and combined heat and power are being considered.

Completed

Dechao Tang

Modelling of Heating and Air-Conditioning Systems

  Completed
(paper copy only)

Paul Tuohy

Control Strategies for Low Energy, Climate Adaptive Buildings

The focus of this project is on the control strategies to allow optimum performance of low energy, climate adaptive buildings. Many examples of buildings exist and it although it has been observed that optimum energy consumption and comfort conditions are difficult to attain across variations in climate, building use and site conditions. This project is utilising integrated building performance simulation to investigate alternative control strategies and thereby eatablish a method for achieving optimum control. The simulation outputs will be validated by application to a real building. The project is sponsored by the BRE Trust and EPSRC.

Ongoing

Gustavo Verela

Electrical Integration of Wind
Turbines Into Industrial Power
Systems.

The exploitation of on-site wind generation in industrial sites is an attractive option since it can reduce the costs associated with conventional generation units. Within an industrial context it is essential that the electrical supply is secure and reliable. This project is researching the impact on power quality of connecting wind turbines to the local electrical supply system. Dynamic modelling tools are being used to assess the impact of alternative load profiles, turbine configurations and wind regimes. This requires the development and verification of detailed mathematical models for the range of wind turbine types. The outcomes from the project are intended to enable developers to assess the feasibility of proposed wind turbines schemes at the design stage and, thereby, determine the optimum operation mode to maintain the quality and security of supply. This project is being undertaken jointly with the Centre for Economical Renewable Power Delivery (CERPD) of the Department of Electronic and Electrical Engineering at the University of Strathclyde.

Ongoing

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