scholarly journals Numerical Approach for the Design of Cost-Effective Renovation of Heating System Control in Buildings

HVAC System ◽  
2018 ◽  
Author(s):  
Alessandro Carbonari ◽  
Massimo Vaccarini ◽  
Emanuela Quaquero
Author(s):  
Kevin Schmaltz

A 30′ × 60′ greenhouse is being installed on the Western Kentucky University Agriculture Department campus farm that will be heated during winter by energy captured during the decomposition of leaves into compost. The bio-generated heat collection and distribution system was designed, and is currently being built and tested by undergraduate mechanical engineering students at WKU. Currently, the WKU Agriculture Department takes all leaves collected by the city of Bowling Green, processing and selling the resulting compost. While the leaves are composting, a temperature of over 150 °F is reached in the center of the leave piles. Student teams have designed and are installing a water piping system below the leaves to capture the waste heat and deliver the water to a root-zone heating system in the greenhouse. The design also includes a subsurface storage tank and auxiliary heating system to extend the capacity of the heating system. It is intended that WKU Agriculture will be able to operate the greenhouse for educational purposes throughout the year, and also provide the design to regional farmers who currently have greenhouses but cannot afford to heat them during Kentucky winters. This paper will detail the design of the heat collection system below the composting leaves, including sizing calculations and experimental verification, to permit uninterrupted composting activities. The root-zone heating system design will also be covered, including sizing calculations of the piping installation within sand beds in the greenhouse. The overall system control, energy storage and supplemental heating will also be discussed. The goal of the project has been to evaluate the feasibility of a cost-effective agricultural heating system for use in moderate climates throughout the United States.


Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 611
Author(s):  
Cecilia Ciacci ◽  
Neri Banti ◽  
Vincenzo Di Naso ◽  
Frida Bazzocchi

In Italy in 2020, only 15.5% of school building heritage was retrofitted from an energy and environmental point of view. In this paper, the cost-optimal method was applied to two different school buildings belonging to the same Italian cold climate zone but characterized by different structural and technological solutions. The research aims at defining the cost-effective redevelopment solution among several ones proposed to apply to this building type. At the same time, this paper provides a critical analysis of the methodology applied, highlighting deficiencies related to a not proper evaluation of environmentally friendly retrofitting measures. In a cost-effective context, the main results show that the intervention on the heating system is more convenient than the retrofitting of the envelope. The energy saving is equal to about 35% for both considered schools. Among the different proposed requalification configurations, the adoption of PV (photovoltaic) electric generation is included. In this regard, an optimization procedure was implemented in a generative design environment to maximize energy production with reference to different design parameters. As a result, a solution with south oriented PV modules with a tilt angle of 42° and arranged in 0.7 m spaced rows proved to be the most effective.


2013 ◽  
Vol 7 (4) ◽  
pp. 28-33
Author(s):  
Monika Pawlita

Background: The methods of heating houses with system components determine the energy-saving systems. Energy-saving solutions allow to maintain comfortable conditions in the house, while minimizing the cost associated with its operation and at the same time helping to protect natural environment. The examples of such solutions include condensing boilers, heat pumps and solar collectors.Material and methods: The object of the analysis in this paper is typical single-family house occupying the area of 150 m². The comparison of analyzed heating system for a single-family house, including modern energy sources, allows the assessment of the most cost-effective method of heating. Results: Choosing rational method of heating for a single-family house is dictated mainly by economic reasons. The efficiency of the heating sources is also very important. In addition, an important factor is a heating period, which depends on the weather conditions in a given year.Conclusions: The costs of fuel/energy are still growing. Fuel selection is determined mainly by fuel calorific value and the price. To select the type of the heating source one must take into account the cost of kWh of heat.


Author(s):  
Christoph Trinkl ◽  
Wilfried Zo¨rner ◽  
Vic Hanby

Both solar and heat pump heating systems are innovative technologies for sustaining ecological heat generation. They are gaining more and more importance due to the accelerating pace of climate change and the rising cost of limited fossil resources. Against this background, a heating system combining solar thermal collectors, heat pump, stratified thermal storage and water/ice latent heat storage has been investigated. The major advantages of the proposed solar/heat pump heating system are considered to be its flexible application (suitable for new and existing buildings because of acceptable space demand) as well as the improvement of solar fraction (extended solar collector utilisation time, enhanced collector efficiency), i.e. the reduction of electric energy demand for the heat pump. In order to investigate and optimise the heating system, a dynamic system simulation model was developed. On this basis, a fundamental control strategy was derived for the overall coordination of the heating system with particular regard to the performance of the two storage tanks. In a simulation study, a fundamental investigation of the heating system configuration was carried out and optimisation derived for the system control as well as the selection of components and their dimensioning. The influence of different parameters on the system performance was identified, where the collector area and the latent heat storage volume were found to be the predominant parameters for system dimensioning. For a modern one-family house, a solar collector area of 30m2 and a latent heat store volume of 12.5m3 are proposed. In this configuration, the heating system reaches a seasonal performance factor of 4.6, meaning that 78% of the building’s and users’ heat demand are delivered by solar energy. The results show that the solar/heat pump heating system can give an acceptable performance using up-to-date components in a state-of-the-art building.


A completed study of a solar hot water heating system installed in a school showed an annual average efficiency of 15%, the low efficiency largely caused by the unfavourable pattern of use in schools. Field studies, in 80 existing and 12 new houses, of a simple domestic hot water system have been initiated to ascertain the influence of the occupants on the actual performance of solar collector systems. The development of testing methods of solar collectors and solar water heating systems is being undertaken in close collaboration with the B.S.I. and the E.E.C. Solar space heating is being investigated in two experimental low energy house laboratories, one using conventional solar collectors with interseasonal heat storage and the other a heat pump with an air solar collector. Studies of the cost-effectiveness of solar collector applications to buildings in the U.K. show that they are far less cost-effective than other means of conserving energy in buildings.


2010 ◽  
Vol 56 (3) ◽  
pp. 219-238 ◽  
Author(s):  
W.J. Chmielnicki

Abstract The annual usage of heat for the demand of heating systems in municipal sector has been estimated as about 650PJ. It is mostly addressed for the demand of central heating systems and hot water consumption. The mode of adopted solutions concerning regulation and control, as well as energy management system, essentially influence its consumption. In the case of residential buildings, the costs of energy constitute the greatest share related to the total cost of building maintenance. Providing buildings with modern digital systems for control and regulation of heating installations is a basic condition enabling their rational usage. In currently employed solutions, algorithms PI or PID are usually applied. However, due to the non-linear properties of heating control systems, they do not secure proper quality. The sequences are often unstable and major control deviations occur. The application of neural networks is an alternative solution to those presently employed. They are especially recommended for adaptive control of non-stationary systems. Such cases occur in heating objects since they demonstrate non-linear properties with a great range of variability of parameters; this especially refers to district heating equipped with flux-through heat exchangers. In this paper, a compile model of heating system control aided by neural networks is presented. The results of the investigation clearly prove the usefulness of such solutions, cause the quality of control is much better than that one applied in traditional systems. Presently, works on the implementation of the proposed solutions are under way.


Sign in / Sign up

Export Citation Format

Share Document