Search results for "Heating system"
showing 10 items of 20 documents
Analysis of Thermal Comfort Conditions and Actual Energy Efficiency for Different Heating Systems in Test Buildings
2015
The aim of this study is detailed analysis of long-term monitoring data on thermal comfort conditions and energy efficiency in small test buildings equipped with different heating systems. Calculations of PPD index and local thermal discomfort factors, as well as actual energy efficiency ratios for different heat pump systems are provided for the test buildings during three weeks of the heating season. It is shown that the type of heating system has an influence not only on heating energy needs, but also on thermal comfort conditions in the room.
Thermal comfort condition assessment in test buildings with different heating/cooling systems and wall envelopes
2017
Abstract The main aim of this study is a comprehensive analysis of long-term monitoring data of thermal comfort and discomfort parameters in small identical test buildings equipped with different heating/cooling systems. Calculations of PPD index expressed the human perception of thermal comfort and such discomfort factors like draught rate and vertical air temperature difference are provided for the room in winter season running three different heating systems – electric heater, air-air heat pump and air-water heat pump, as well as for the summer cooling with split type air conditioning systems. It is shown that the type of heating/cooling system and its working regime has a significant im…
A cellular automaton based model simulating HVAC fluid and heat transport in a building. Modeling approach and comparison with experimental results
2010
A discrete model characterizing heat and fluid flow in connection with thermal fluxes in a building is described and tested against experiment in this contribution. The model, based on a cellular automaton approach, relies on a set of a few quite simple rules and parameters in order to simulate the dynamic evolution of temperatures and energy flows in any water or brine based thermal energy distribution network in a building or system. Using an easy-to-record input, such as the instantaneous electrical power demand of the heating or cooling system, our model predicts time varying temperatures in characteristic spots and the related enthalpy flows whose simulation usually requires heavy comp…
Multicriteria evaluation of sustainable energy solutions for Colosseum
2017
Abstract Colosseum is a large office building in the capital region of Finland. The building owner operates on the highly competitive office rental market. With increasing emphasis on environmental responsibility, energy efficiency and sustainable energy solutions can provide competitive edge on the rental market. This study evaluates in terms of multiple criteria different alternatives to enhance the energy solutions of the building. The alternatives included different configurations of solar power, ground source heat, and roof constructions, along with district heating. Decision criteria included internal rate of return, energy efficiency, CO2 emissions, and attractiveness. Attractiveness…
Multicriteria evaluation of carbon-neutral heat-only production technologies for district heating
2018
Climate change mitigation requires reducing dependence on fossil fuels and transition to low carbon energy production technologies. Nearly half of the global final energy consumption is thermal energy produced from technologies with high carbon dioxide emission. As such, it is imperative to employ carbon-neutral heat production to achieve a sustainable energy system. This paper presents a real-life case of applying multicriteria decision analysis for evaluating carbon-neutral heat-only production technologies in a major district heating system in Finland. A group of 10 experts from the energy company contributed in defining the alternative technologies and multiple economic, technological, …
A dish-stirling solar concentrator coupled to a seasonal thermal energy storage system in the southern mediterranean basin: A cogenerative layout hyp…
2020
Abstract In the future, renewable energy sources will increasingly represent an efficient energy source capable of meeting the demands of residential and industrial buildings avoiding the emissions of greenhouse gases into the atmosphere. In this paper, a heat and electric power cogeneration plant implementing a field of dish-Stirling collectors, a seasonal geothermal storage and a system of water-to-water heat pumps is proposed for the first time. The cogeneration plant has been designed both to supply thermal energy to the heating system of Building 9 of the Department of Engineering in Palermo and to produce electricity. The operation of the plant has been tested by means of hourly-based…
Artificial Intelligence in Protecting Smart Building’s Cloud Service Infrastructure from Cyberattacks
2020
Gathering and utilizing stored data is gaining popularity and has become a crucial component of smart building infrastructure. The data collected can be stored, for example, into private, public, or hybrid cloud service infrastructure or distributed service by utilizing data platforms. The stored data can be used when implementing services, such as building automation (BAS). Cloud services, IoT sensors, and data platforms can face several kinds of cybersecurity attack vectors such as adversarial, AI-based, DoS/DDoS, insider attacks. If a perpetrator can penetrate the defenses of a data platform, she can cause significant harm to the system. For example, the perpetrator can disrupt a buildin…
Technical challenges in the construction of the steady-state stellarator Wendelstein 7-X
2013
The next step in the Wendelstein stellarator line is the large superconducting device Wendelstein 7-X, currently under construction in Greifswald, Germany. Steady-state operation is an intrinsic feature of stellarators, and one key element of the Wendelstein 7-X mission is to demonstrate steady-state operation under plasma conditions relevant for a fusion power plant. Steady-state operation of a fusion device, on the one hand, requires the implementation of special technologies, giving rise to technical challenges during the design, fabrication and assembly of such a device. On the other hand, also the physics development of steady-state operation at high plasma performance poses a challeng…
Analysis and Improving Methods of Efficiency of Solar Energy in Municipal Heating System
2011
This paper introduces the current state of solar heating system among Wanzleben city heating net. In view of low efficiency (only 20-30%) of this system, it analyses the shortcomings of this applied system from sensors' situation, fixed flow problem, the influence of the user's water temperature and the length of pipe separately. Some improving methods which are effective by theoretical analysis are suggested. The implementation steps have to be discussed in more detail with the utility.
Techno-economic analysis of a local district heating plant under fuel flexibility and performance
2017
Brovst is a small district in Denmark. This paper analyses the use of local renewable resources in the district heating systems of Brovst. The present use of fossil fuels in the Brovst district heating plant (DHP) represents an increasing environmental and climate-related load. Therefore, an investigation has been made to reduce the use of fossil fuels for district heating system and make use of the local renewable resources (biogas, solar, and heat pump) for district heating purposes. In this article, the techno-economic assessment is achieved through the development of a suite of models that are combined to give cost and performance data for this district heating system. Local fuels have …