Advanced fuzzy logic based control systems for an institutional building in subtropical climate

Building management systems (BMS) have the ability to monitor and control buildings mechanical and electrical systems, such as heating, ventilation and air conditioning (HVAC) and lighting systems, for providing indoor thermal comfort and reducing energy consumption. However, most HVAC systems are controlled using conventional controller the functions of which are based on ON/OFFs controller and Proportional-Integral-Derivative (PID) controllers. These controllers are not efficient at saving energy because of the operations of HVAC systems are nonlinear. Thus, the implementation of fuzzy-logic-based control systems within smart buildings are necessary as they are more efficient and will consequently reduce building energy consumption as well as negative impacts on environment. The main aim of this study was to design and develop an advanced fuzzy-logic-based controller for HVAC and indoor lighting systems for an institutional building in subtropical Central Queensland (Australia) to assess its energy and environmental performances, and compare these with the performances of conventional ON/OFF and PID controllers. The fuzzy-logic-based model and control strategies were designed and developed to control indoor temperature, humidity, air quality, air velocity, daylight integration, thermal comfort and energy balance. In addition, the model for indoor temperature and humidity transfer matrix, uncertainties of users’ comfort preference set-points and a fuzzy algorithm were developed. The performances of both ON/OFF and PID control system, and proposed fuzzy-logic-based control systems were simulated using MATLAB software. DAYSIM software was used to simulate the illuminance of lighting system. DesignBuilder and EnergyPlus software were used to develop case study building layout and thermal performance modelling. The simulation was done for indoor and outdoor temperature and humidity control, indoor air quality, and illuminance control. The simulated results were analysed on the basis of real-life events such as the usage of ambient air when its temperature and humidity matches indoor thermal comfort set-point, the usage of existing daylighting rather than the usage of electric lighting, and the consideration of the building’s occupancy level taking into account the controllers’ execution performance panel containing response speed, overshot and robustness adaptability. It was found that an energy savings of about 10% can be achieved if fuzzy-logic-based controllers are introduced compared to conventional PID controllers at full occupancy level for the case study building’s HVAC and lighting systems. The simulation was also done for 50% occupancy and 25% occupancy levels which indicated an energy savings of about 14% at 50% occupancy level, and 24% at 25% occupancy level compared to full occupancy at a given time. In addition, life cycle costs savings of about 20.5% can be achieved using the proposed fuzzy-logic controller. The systems payback period is expected to be nine years, and the system is able to reduce greenhouse gas emissions of 25.5 tonnes of CO2 per annum from the case study building. The thesis has contributed to the process development and design of advanced fuzzy logic controllers for smart buildings in subtropical climate of Australia which is a successful alternative to conventional control systems especially where indoor air quality and mould growth issue is a big concern, e.g. in hospitals, libraries and museums. The novelty of this work is the development of an energy efficient and environment friendly control of HVAC and lighting systems using real life and time events such as ambient air, day-light and actual occupancy levels which have not been addressed previously within an Australian institutional building, specifically under the subtropical climate conditions. Thus, the outcomes of the study will provide designers, developers and decision makers with the essential information and knowledge of applications of advanced fuzzy logic control system for smart buildings

Potential of saving energy using advanced fuzzy logic controllers in smart buildings in subtropical climates in Australia

Subtropical Regions in Australia are associated with high demand for air conditioning throughout the long Summer which leads to a high energy consumption and consequently high greenhouse gas (GHG) emissions which has a high negative impact on the environment. Using conventional controllers in Building Management Systems (BMS) whose functions are based on ON/OFF, temperature control and in some cases humidity control is not the ultimate solution to save energy. The reason behind the above fact is that, conventional controllers do not take into account real time events such as the number of occupants, indoor air quality (IAQ), natural light illuminations and etc dislike Fuzzy logic based controllers. In the last decade there is a high interest in researching Fuzzy logic based controllers as they have the ability to save energy while maintaining indoor comfort level. In this article a general review on Fuzzy logic based controllers is presented, focusing on the role of technology in saving energy, and its potential in subtropical Central Queensland, Australia. The issues of past and present techniques are highlighted and discussed accordingly

Design and development of advanced fuzzy logic controllers in smart buildings for institutional buildings in subtropical Queensland

© 2015 Elsevier Ltd.Building management system (BMS) has the ability to monitor and control buildings' mechanical and electrical equipment namely heating, ventilating and air conditioning (HVAC), lighting, power, fire and security systems. BMS can also provide indoor thermal comfort within commercial buildings including industrial and institutional buildings and able to reduce energy consumption. However most of HVAC systems are controlled by using conventional controller whose functions are based on ON/OFF controller and Proportional-Integral-Derivative (PID) controllers. These controllers are not the ultimate solution to save energy because the operations of HVAC systems are nonlinear. Thus, the implementation of fuzzy logic controllers within smart buildings will be more efficient which consequently will save more energy and money. This paper reviews, investigates and evaluates the use of fuzzy logic controller in HVAC systems and light controllers for smart buildings in subtropical Australia as well as highlights the role of technology in saving energy, and its potential. Additionally, it highlights the recent developments in BMS controllers including its conceptual basis, capabilities and limitations

The integration of day light with advance fuzzy based controllers for institutional buildings in the region of Central Queensland, Australia

Smart buildings lately have gained momentum due to its ability to drive, manage and control energy conservation measures. Fuzzy based controllers in Building Management Systems (BEMS) can use the latest and the most innovative control strategies in order to achieve a comfortable life style while savings energy and reducing greenhouse gas emissions. This system uses real life events as a point of control. Those real life events may include day-light usage (natural light), occupancy profile, passive cooling techniques and the usage of ambient atmosphere based on its ambient temperature and humidity. This paper develops a BMS using advanced fuzzy based controllers with integration of day light. This control strategy is based on quantifying the outside and the inside illuminance and allowing an add-on controller to perform a photometric calculation and comparison to decide rooms openings (windows). The paper also analyses energy savings and recommend suitable markets for this control strategy either during the design stage of a building, or after the building construction or retrofitting

Energy savings by fuzzy base control of occupancy concentration in institutional buildings

As a part of global efforts to minimize reliance of fossil fuel and in order to minimize greenhouse gas emissions, smart buildings become a part of the solution as it is able to utilize real life events such as daylight, the usage of ambient air and it also is able to perform a head count and then adjust accordingly the heating ventilation and air conditioning HVAC system and the lighting system as well. Consequently this paper study and analyze the effect of building occupancy concentration on total electric demand. The case study was performed at Building 19 of Rockhampton campus of Central Queensland University using EnergyPlus simulation engine

Recent developments of advanced fuzzy logic controllers used in smart buildings in subtropical climate

Building management system (BMS) has the ability to monitor and control buildings’ mechanical and electrical equipment including namely heating, ventilating and air conditioning (HVAC), lighting, power, fire and security systems. BMS can also provide indoor thermal comfort within commercial buildings including industrial and institutional buildings and able to reduce energy consumption. However most of HVAC systems are controlled by using conventional controller whose functions are based on ON/OFF controller and Proportional-Integral-Derivative (PID) controllers. These controllers are not the ultimate solution to save energy because the operations of HVACsystems are nonlinear. Thus, the implementation of fuzzy logic controllers within smart buildings will be more efficient which consequently will save more energy and money. This paper reviews, investigates and evaluates the use of fuzzy logic controller in HVAC systems and light controllers for smart buildings in subtropical Australia. Additionally, it highlights the recent developments in BMS controllers including its conceptual basis, capabilities and limitations

Optimization of advanced fuzzy based control system of institutional building management system (BMS) in Australian subtropical climate

A significant number of institutional buildings in Australia are quite old and not energy efficient. The main reason behind this is that, most of these buildings are controlled using conventional building management system (BMS) which relies on static temperature set points for heating, ventilation and air conditioning (HVAC) system and the ON/OFF control system for lightings. Use of advanced fuzzy logic controllers in BMS is essential to increase both, institutional buildings’ energy savings and buildings’ control system efficiency. Advanced fuzzy logic controllers allow utilization of real life events such as natural light availability, the status of ambient air to heat or cool the building, the determination of actual indoor thermal load by performing head count (occupants’ number), etc. In this paper an advanced fuzzy based controller is optimized and analysed in order to decide the proposed system (i.e. fuzzy based control system) adaption as well as the proposed system’s add-on possibility to the building’s existing control system. The building is located at subtropical Rockhampton campus of Central Queensland University, Queensland, Australia. The controller examined and used are: solar irradiation (natural light), head count, shading possibilities of windows and humidity status which will lead to mechanical and electrical load reduction. The early stage of system optimisation showed that, the proposed system has potential in saving energy, reducing greenhouse gas emission and improving indoor air quality (IAQ) which is presented and discussed in this paper

An overview of solar assisted air conditioning in Queensland's subtropical regions, Australia

Australia has a very sunny climate, with a very high demand for air conditioning. Relying on electricity to drive, buildings' HVAC systems will cause a significant negative impact on the environment. In this paper, recent developments in solar assisted air conditioning technologies are reviewed and presented. The conceptual basis of the technologies including open and closed cycles cooling technologies, capabilities and limitation are discussed. Energy demand, energy consumption by Australian buildings sector and economic and environmental problems associated with the usage of fossil fuel resources are reported. Second the issue of mould growth and indoor thermal comfort and indoor air quality is highlighted. Finally the technology fundamentalsand theories involved with solar energy and solar collector's technologies are summarised and discussed

An overview of solar cooling technologies markets development and its managerial aspects

Commercial buildings consume a considerable amount of fossil fuel that directly has negative impacts on the environment. In fact this leads to significant greenhouse gas emissions and the production of non-environmental friendly materials. Hence global warming is the most common dilemma facing world governments at the present time. Solar cooling technologies proved to be a successful alternative for conventional cooling systems especially in hot and sunny climates. The solar cooling technologies are able to reduce electricity demand since it relies on solar energy to produce cooling. There are many research articles that focus on the solar cooling technologies technical and engineering developments meanwhile there are limited research activities detailing its barriers, opportunity, architectural and managerial aspects. This research paper outlines the potential markets of solar cooling systems, as well as their architectural and managerial implications. The article also discusses, and suggests recommendations to overcome issues and barriers during solar cooling systems installation phase. In addition the article presents the solar cooling systems industry markets development and the potential of implementing the solar cooling technologies in livestock storage facilities, crops drying business, hospital