Search results for "Heating"
showing 10 items of 248 documents
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…
A novel solar trigeneration system integrating PVT (photovoltaic/thermal collectors) and SW (seawater) desalination: Dynamic simulation and economic …
2014
Abstract The paper investigates the integration of renewable energy sources and water systems, presenting a novel solar system producing simultaneously: electrical energy, thermal energy, cooling energy and domestic water. Such system is designed for small communities in European Mediterranean countries, rich in renewable sources and poor in fossil fuels and water resources. The polygeneration system under analysis includes PVT (photovoltaic/thermal solar collectors), a MED (multi-effect distillation) system for SW (seawater) desalination, a single-stage LiBr–H2O ACH (absorption chiller) and additional components, such as storage tanks, AHs (auxiliary heaters) and BOP (balance of plant) dev…
A back to back method for the temperature rise test of prefabricated substations: A case study
2015
In this work a back to back method is presented which allows to develop heating tests of prefabricated secondary substations with a limited number of supplying equipment (an induction regulator and a capacitor bank). The proposed method makes use of the transformer tap changers to create a voltage difference on the medium voltage side. In this way, only an adjunctive low voltage supply is needed. With the proposed test system, the heating tests are developed on a 1000 kVA prefabricated substation. Thanks to the experimental tests, the class of enclosure of the substation and the operating temperature and resistance of the power transformers are determined, according to the recommendations o…
Multicriteria evaluation of heating choices for a new sustainable residential area
2015
Abstract The city of Loviisa in Finland is planning a new sustainable residential area with a total of 240,000 m2 of residential houses and apartment buildings with services. The city wants to promote sustainable energy solutions in the area, considering various renewable energy forms for heating. The aim of this research is to evaluate which heating system would be best for a new single-family house when different technical, economic, environmental and usability criteria are considered. A group of experts evaluated the alternative heating systems with respect to the criteria. The citizens were involved with a questionnaire to provide preference information for different criteria. Altogethe…
Experimental Research of Thermal Comfort Conditions in Small Test Buildings with Different Types of Heating
2015
Abstract The aim of this study is detailed analysis of long-term monitoring data of thermal comfort conditions and energy efficiency in small test buildings equipped with different heating systems. Calculations of PPD index and local thermal discomfort factors are provided for the test buildings during three weeks of heating season. It is shown that the type of heating system has influence not only on heating energy need, but also on thermal comfort conditions in the room.
Reducing the Cost of Being the Boss: Authentic Leadership Suppresses the Effect of Role Stereotype Conflict on Antisocial Behaviors in Leaders and En…
2021
What drives entrepreneurs to engage in antisocial economic behaviors? Without dismissing entrepreneurs’ agency in their decision-making processes, our study aims to answer this question by proposing that antisocial economic behaviors are a dysfunctional coping mechanism to reduce the psychological tension that entrepreneurs face in their day-to-day activities. Further, given the overlap between the male gender role stereotype and both leader and entrepreneur role stereotypes, this psychological tension should be stronger in female entrepreneurs (or any person who identifies with the female gender role). We argue that besides the well-established female gender role – leader role incongruence…
Trigeneration and Polygeneration Configurations for Desalination and Other Beneficial Processes
2018
Abstract The integration of renewable energy sources (geothermal, biomass, and solar) and desalination systems into novel polygeneration plants is investigated. Two main arrangements are considered: geothermal (GP) and biomass (BP) polygeneration. Both systems include concentrating photovoltaic/thermal solar collectors, a multieffect distillation system for seawater desalination, a single-effect LiBr-H2O absorption chiller, storage tanks, heat exchangers, balance-of-plant devices; a biomass auxiliary heater and geothermal wells are also included, in BP and GP, respectively. The systems can provide electricity and hot water, used for space heating, cooling, domestic hot water production, and…
Thermoeconomic optimization of a renewable polygeneration system serving a small isolated community
2015
During the last years, special attention has been paid to renewable polygeneration technologies, able of simultaneously producing thermal, cooling, electrical energy and desalinated water from seawater. This paper focuses on an innovative polygeneration system driven by renewable energy sources, including the following technologies: hybrid photovoltaic/thermal collectors, concentrating parabolic trough (CPVT), a biomass heater, a single-stage absorption chiller and a multiple-effect distillation desalination system. The system is designed to cover the base load of an isolated small community. In previous papers, the dynamic simulation model about plant operation is discussed. In this paper,…
Exergetic and exergoeconomic analysis of a renewable polygeneration system and viability study for small isolated communities
2015
Abstract A great interest has recently arisen for the sustainable supply of energy and fresh water, due to the growing demand from developing countries. Facing this demand by traditional technologies implies evident risks related with the high cost of fossil fuels and their environmental impact. Then, alternative solutions based on the use of renewable sources and innovative technologies must be considered. In this paper a renewable polygeneration system is examined, which includes a solar field based on parabolic trough photovoltaic/thermal collectors, a biomass heater, an absorption chiller and a Multiple Effect Distillation desalination unit. Plant operation under dynamic conditions has …
A methodology for selecting a sustainable development strategy for connecting low heat density consumers to a district heating system by cascading of…
2021
Abstract The paper presents a methodology for supporting the decision making on how to sustainably develop an existing district heating system when consumers located in a remote, low-heat consumption density area are connected to the system. Several scenarios are proposed where a multi-generative system is assessed by implementation of industrial heat pumps (HP), solar photovoltaic (PV) system, and low-temperature regime into an existing district heating system in various combinations. The methodology is based on multi-criteria analysis allowing for energy, economic, exergy, and environmental (4E) assessment. The research is based on a case study of an autonomous district heating system in …