D. Kolokotsa

Advanced fuzzy logic controllers design and evaluation for buildings’ occupants thermal–visual comfort and indoor air quality satisfaction

The aim of this paper is to present and evaluate control strategies for adjustment and preservation of air quality, thermal and visual comfort for buildings’ occupants while, simultaneously, energy consumption reduction is achieved. Fuzzy PID, fuzzy PD and adaptive fuzzy PD control methods are applied. The inputs to any controller are: the PMV index affecting thermal comfort, the CO2 concentration affecting indoor air quality and the illuminance level affecting visual comfort. The adaptive fuzzy PD controller adapts the inputs and outputs scaling factors and is based on a second order reference model. More specifically, the scaling factors are modified according to a sigmoid type function, in such a way that the measured variable to be as closer as possible to the reference model. The adaptive fuzzy PD controller is compared to a non-adaptive fuzzy PD and to an ON–OFF one. The comparison criteria are the energy required and the controlled variables response. Both, energy consumption and variables responses are improved if the adaptive fuzzy PD type controller is used. The buildings’ response to the control signals has been simulated using MATLAB/SIMULINK.

Review on methodologies for energy benchmarking, rating and classification of buildings

The energy benchmarking, rating and classification of buildings are necessary procedures for energy certification scheme adoption, energy regulation establishment, energy-efficiency promotion and energy consumption reduction, according to the Directive 2002/91/EC and its implementation in EU member states. The aim of this paper is to investigate and present research works, tools and programs focused on energy benchmarking methods, energy rating procedures and classification schemes for the building sector. The European Committee for Standardization method of benchmarking and rating for buildings are analyzed, as well as a proposed integrated classification method based on the application of clustering techniques to virtual building data sets of office buildings in Greece.

Interconnecting smart card system with PLC controller in a local operating network to form a distributed energy management and control system for buildings

Distributed control and energy management for buildings is a viable solution, ensuring both indoor comfort for the occupants and reduction of energy consumption. The aim of this paper is to present the architecture of a distributed building energy management system that can be installed in new as well as in existing buildings, which are more energy inefficient. The system integrates a smart card unit, acting as a user machine interface, sensors, actuators, interfaces, a PLC controller that incorporates the fuzzy control algorithm, local operating network (LON) modules and devices and an optional PC which monitors the performance of the system. The distributed control architecture is based on the properties of the LON. The complete system is installed and tested in the Laboratory of Electronics of the Technical University of Crete.

Passive Solar Architecture

A building’s energy consumption is a major source of greenhouse gas emission and one of the main causes of climatic change. Passive solar architecture relies on the use of techniques for solar and heat control, heat amortization, and heat dissipation. Solar and heat protection or exploitation techniques may involve thermal improvement by the use of outdoor and semi-outdoor spaces, layout and external finishing, solar control and shading of building surfaces, thermal insulation, control of internal gains, and so on. The aim of this chapter is to present an overview of solar architecture starting from its history and provide a short description of the solar architecture basics, followed by an account of the state-of-the-art developments regarding the building fabric, cool materials, and intelligent control techniques. The future research trends are revealed and discussed here.

LOCAL OPERATING NETWORKS TECHNOLOGY AIMING TO IMPROVE BUILDING ENERGY MANAGEMENT SYSTEM PERFORMANCE SATISFYING THE USERS PREFERENCES

The available Building Energy Management Systems (BEMS), although they contribute to a significant reduction of energy consumption and improvement of the indoor environment, they can only be implemented in new buildings. Their installation in existing buildings is far from being cost effective due to the incompatibility of communication protocols between BEMS designed by various manufacturers and unavoidable modifications for data transmission. On the other hand, current research for energy efficient buildings has proved that although the design and the facilities including BEMS aim to satisfy the thermal and visual comfort plus the air quality demands while minimising the energy needs, they often do not reach their goals due to users interference. Latest trends in designing Intelligent Building Energy Management Systems (IBEMS) offer a Man Machine Interface that could store the users preferences and adapt the control strategy accordingly. The objectives of the present paper are to present the advantages of the use of a man machine interface based on a smart card terminal together with fuzzy control techniques in satisfying the users preferences plus to underline the capabilities that the LON network offers to the design. A fuzzy PID controller is developed to reach the first of the above objectives. The monitoring of the energy consumption along with satisfying the users preferences is achieved by the use of a suitable cost function for the whole system. All the above parameters as well as the cost function are kept between acceptable limits. The overall control system including the cost function is modeled and tested using MATLAB/SIMULINK. The implementation of the control system in an existing building requires interconnection of sensors and actuators installed across the building, is well served by the LonWorks technology due to its high standards and flexibility features.

Energy analysis of zero energy schools: the case study of child’s asylum in Greece

ABSTRACT School buildings constitute a rather special case of buildings when it comes to energy performance since the operational costs for heating, cooling and ventilation are usually far less important than the achieved thermal comfort, indoor air quality and lighting levels due to the very sensitive subject of students’ health, well-being and ability to attend lessons Moreover, there is a significant margin for improvement in school buildings’ energy performance and indoor environmental quality. The aim of the present paper is to present the design and energy technologies of a zero energy school in Greece. The energy performance of the zero energy building is analysed. A reduction of the energy demand by almost 68% is accomplished while a significant improvement of the indoor thermal comfort is achieved through the zero energy building design.

The use of algorithms for light control

Because light directly influences human health, requirements on lighting levels must be constantly fulfilled. The lighting control market represents, therefore, an innovative sector that empowers a start-ups potential and where customers are highly looking for solutions that have low costs and high life expectancy, and that are least intrusive. Consequently, the control algorithms implemented are crucial in order to maximize efficiency while satisfying all the aforementioned specifications. This chapter introduces light-control algorithms as enabler of differentiation, which is a key requirement for a successful start-up rollout. Moreover, the proposed control lighting systems are customized and implemented in three real operational environments: two hospitals and one office building, all located in the Mediterranean area. The implementations show significant energy savings with low up-front and installation costs: this demonstrates the importance of control algorithms in lighting systems as high energy savings are achieved and lighting requirements fulfilled.