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Knowledge accumulated in the past from observed construction failures has formed the basis for a predictive capability. More recently, it has been observed that interactions between energy efficien...

The discussion in this article starts in the 1920s, that is, at the time of the humble beginnings of building science and brings us to 2020s with the development of net-zero energy buildings. The knowledge accumulated by explaining observed failures in the practice of construction slowly formed a basis for moving toward a predictive capability and to an integration of modeling and testing. Furthermore, we have learned that interactions between energy efficiency, indoor environmental quality, and moisture management are so critical that the three issues must be considered simultaneously. Effectively, a change in the low energy is needed to ensure durability of materials and cost considerations for these buildings. At this stage, one could observe a clear change in the mind-set of the scientific community. Forty years after construction of the first 10 passive homes, we made a shocking observation—an adequate technology has been developed, but our lack of vision prevents effective use of this technology. Again, we need to modify our vision and change the design paradigm to balance comfort, building durability, and cost-effectiveness. If the quest for sustainable buildings is our ultimate objective, then we should learn more from the surrounding nature; termites appear to master the art of hygrothermal control better than humans because they can optimize transient conditions to maintain a stable interior comfort zone. Thus, in the article to follow a new compact building envelope design package is proposed, applicable to different climates with specific modifications of critical hygrothermal material properties. This approach is called the Environmental Quality Management. This will be the second step for a building science (physics) needed to become a leading force in the transition to sustainable built environments.

In this paper series, we will examine the relation between the smart grid and the next generation of buildings. The new objective is now to design buildings so that the energy exchange takes place in time suitable for both sides. The building takes energy from the grid and give it back at different time because in the next generation of buildings they are equipped in advanced control system that controls energy storage for several hours and the new or retrofitted building can eliminate energy peaks and valleys for itself and assist the smart grid in equalization of the load. The control systems include monitoring and modeling of energy use and indoor environment to arrive to a weather-based prediction, Therefore, in part 1 of the paper series we address collecting, processing and analysis of the measurement data that can be done by the new modular statistical software alone or in conjunction with a dedicated neural network. We want to minimize energy use and maximize the thermal comfort of the occupants. Using the modular structure of the database, data transformation technologies and other existing tools, the modular statistical software (MSS) has been created to process large amounts of data as input to the decision-making algorithm. This is to enable buildings automated control (BAC) to take over the control of heating/cooling, ventilation, illumination and other performance aspects that relate to sustainability of built environment.

Growing popularity of buildings with integrated sub-systems, requires a review of methods to optimize the preheat of ventilation air. An integrated system permits using geothermal heat storage parallel to the direct outdoor air intake with additional treatment in the mechanical room as a part of building automatic control system. Earth Air Heat Exchanger (EAHX) has many advantages but also has many unanswered questions. Some of the drawbacks are: a possible entry of radon gas, high humidity in the shoulder seasons as well as the need for two different air intake sources with a choice that depends on the actual weather conditions. While in winter, the EAHX may be used continuously to ensure thermal comfort, in other seasons, its operation must be automatically controlled. To generate the missing information about the EAHX technology we have examined two nearly identical EAHX systems, one placed in ground next to the building and the other under the basement slab. In another project, we have reinforced the ground storage action by heat exchanger placed on the return pipes of the hydronic heating system. Effectively, the information provided in this paper, shows advantages of merging both these approaches while the EAHX could be placed under the house or near the basement foundation that is using an exterior basement insulation.

The concept of environmental quality management has been described in papers [1 - 4] that looked at the next generation of low energy buildings from the point of view of the occupant. Optimizing energy use is difficult for a few reasons: presence of dramatic changes in the manner we design and operate buildings, change in the role of an architect who must be a leader of interacting team, often quality management is biased towards the design more than on performance of the finished product and finally the need for integrated monitoring and modeling in the occupancy stage. Effectively, we are integrating heating/cooling and ventilation with the structure at the same time as we verify the appropriateness of the new methods to evaluate performance of these systems. In this process we require double controls, one by the occupant and the other by the computerized (smart) control system. The traditional approaches to modify human behavior generally failed because occupants were not given enough control over their environment. Thus, a major part of the trend to a low-carbon, climate resilient future will be focused on methodology to include path from a complex field testing of building performance to simplified testing that combined with simple monitoring and data from utilities would allow assessment of the energy and carbon emission in a district of a city. Our experience shows that preliminary design must be optimized during the period of service for all more complex buildings such as large residential, office or commercial buildings. In this context the artificial neural network approach appears to have significant advantages. Yet, traditionally ANN requires large data set to establish functional relations during the learning stage and therefore the first question is how precise can the control of temperature be when the heat exchanger is subjected to different climatic conditions.

Computer simulations of buildings in the context of improving their energy efficiency, performed by the Design Builder – type computer programs, are a very useful tool. However, in the case of simulation studies on the impact of automatic control systems on the energy efficiency of buildings, the results are often overly optimistic. Energy savings are overestimated in comparison to the results achieved in the real environments. Therefore the results obtained by the simulations should be validated in a real environment. The Małopolska Laboratory of Energy Efficient Building (MLBE) of Cracow University of Technology provides an opportunity to perform an experimental real scale research of the building automation systems to improve the buildings energy efficiency and occupants’ comfort. This paper presents a part of the multi-source cooling system with selected cooling sources and room’s cooling methods, implemented in the MLBE building. The purpose of the summer study was to verify the work of selected technical equipment and installations that realize the cooling process in actual conditions. A gas heat pump and a passive cooling system using the cooling capacity of the soil were used. Furthermore, the fan coil units and the plane systems were used at the room level. Together with the possibilities of the building automation and control system implemented in MLBE, the results shown in this paper will become – in the future planned research – a base for creating optimized algorithms for controlling the studied system in the context of the search for energy-efficient installation and programming solutions. The obtained results will form the basis to develop more effective control strategies for the tested cooling system, both in the economic context as well as in the context of the required users´ comfort.

Due to the increasing requirements in the field of buildings’ energy saving, impossible to meet only due to the thermal insulation of the building envelope, it is necessary to pay attention to the energy efficiency of technical installations and application of automatic control systems. Computer simulations on the building structure or functioning of its individual installations in the context of limiting its energy consumption, performed by Design Builder – type computer programs, are a very useful tool. However, in the case of simulation studies on the impact of automatic control systems on energy efficiency, the results are often overly optimistic – they are overestimated in comparison to results achieved in actual environments. Therefore, the results obtained should be validated in an actual environment. This paper presents the Małopolska Laboratory of Energy Efficient Building (MLBE) of Cracow University of Technology, which provides an opportunity to perform experimental actual scale research of building automation systems to improve buildings energy efficiency and occupants’ comfort. This paper includes a detailed description of MLBE’s building automation and control system. Furthermore, this paper presents possibilities and an example methodology of energy efficiency’s experimental study using BACS system.

Energy-efficient buildings are increasingly equipped with modern automation and control systems that enable significant energy savings by providing energy in the exact place and time of the demand. Moreover, high-performance LED light sources are used as interior lighting. Since the computers, automation system controllers and LED light sources require a lower voltage than the mains voltage, the buildings use a large number of power electronic converters adjusting the power supply conditions for the devices being serviced. Operation of this type of strongly non-linear receivers leads to an increase in transmission losses of electrical energy related to reactive power flow and generation of higher harmonics. Striving to reduce energy consumption in buildings leads to increasing use of these devices, which in consequence will aggravate the problem of insufficient quality of electricity. The paper discusses the provisions of standards for the quality of electricity. The paper presents the results of research on the quality of electricity in the Malopolska Laboratory of Energy Efficient Building – an experimental building equipped with a building automation and control system.