Search results for "Air conditioning"
showing 10 items of 67 documents
Analysis of some renewable energy uses and demand side measures for hotels on small Mediterranean islands: A case study
2018
Abstract Tourist activity strongly influences the energy consumption and the overall load profile of communities with isolated energy systems. One example is hotel sectors on small islands that are not connected to mainland energy distribution grids. The use of solar energy systems could be a smart option for reducing energy consumption and tackling seasonal fluctuation. The operation of a weak and isolated electric grid requires attention to the management of power profiles in very short time frames. Energy storage (thermal or electric), as well as building automation control technologies, can be utilised for these aims. In this context, the present paper illustrates a study conducted at a…
A methodology for evaluating the flexibility potential of domestic air-conditioning systems
2020
The paper presents a methodology for quantifying the electrical flexibility potential of air-conditioning systems (ACS) installed in residential buildings according to the building envelope characteristics and the ACS performance. In order to provide a thorough analysis of the issue, the ACS baseline consumption referred to the indoor temperature of 24°C has been computed for three typical residential buildings built in the South of Italy over different periods. The baseline consumption was used as a reference to estimate the effect of the set point temperature change on the ACS power profile. The results showed that increasing the set-point temperature of ACS by 2°C and 4°C leads to a redu…
A correlation linking the predicted mean vote and the mean thermal vote based on an investigation on the human thermal comfort in short-haul domestic…
2015
Abstract The results of an experimental investigation on the human thermal comfort inside the cabin of some Airbus A319 aircrafts during 14 short-haul domestic flights, linking various Italian cities, are presented and used to define a correlation among the predicted mean vote (PMV), a procedure which is commonly used to assess the thermal comfort in inhabited environments, and the equivalent temperature and mean thermal vote (MTV), which are the parameters suggested by the European Standard EN ISO 14505-2 for the evaluation of the thermal environment in vehicles. The measurements of the radiant temperature, air temperature and relative humidity during flights were performed. The air temper…
Energy-saving potential of ground source multiple chillers in simple and hybrid configurations for Mediterranean climates
2022
Air conditioning accounts for a large share of energy usage in residential and tertiary sectors. Renewable energy technologies offer promising solutions to reduce the environmental impacts of meeting buildings’ energy loads. The possibility of using the soil as a thermal reservoir for heating and cooling systems has gained growing attention in the last decade due to its high potential for energy saving. In this paper, the benefits achievable using ground source chillers for air conditioning in an office building located in Southern Italy are discussed. A multiple chillers system coupled with a borehole heat exchanger is investigated and compared to conventional air-cooled and water-cooled s…
Adopting magnetocaloric heat pumping and refrigeration for electrical vehicle
2017
International audience; Refrigeration process is based on conventional gas compression and expansion techniques. However, this technique has numerous disadvantages since it generates greenhouse gas and is partly responsible for global warming. This paper exposes analternative method: magnetocaloric refrigeration that presents the advantage to combine high-energy efficiency and respect of theenvironment. Magnetic heat pumping and cooling is compared to conventional method applied on vehicle air conditioning system.Simulation results are used to demonstrate the approach.
People comfort and artwork saving in museums: comparing indoor requisites
2009
In museums, environmental indoor conditions should, contemporaneously, preserve the exhibited works of art and ensure the comfort conditions for people. Unfortunately, human and artworks requirements are characterised by different values of the physical indoor parameters that, occasionally, could become conflicting. In the paper, these problems are addressed by means of a literature analysis, with a specific attention to thermal comfort conditions of people. The possibility of finding common ranges of values for both requisites is finally discussed. Some recent technical recommendations on the matter have also been considered for indicating some HVAC equipment and appliances to be adopted i…
Monitoring results and analysis of thermal comfort conditions in experimental buildings for different heating systems and ventilation regimes during …
2017
This paper focuses on the long-term monitoring of thermal comfort and discomfort parameters in five small test buildings equipped with different heating and cooling systems. Calculations of predicted percentage of dissatisfied people (PPD) index and discomfort factors 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 an important impact on thermal comfort conditions in observed room. Recommendations for the optimal operating regimes and choice o…
Building integrated solar thermal design: assessment of performances of a low cost solar wall in a typical Italian building
2016
Abstract Present work deals with the topic of building integration of solar thermal collector (BIST) as a refurbishment measure. Such equipment, more than its main function as heating generator, plays a specific role as a building component (envelope finishes, thermal insulation layer, roof cover etc). Consequently, from a heat transfer point of view, an integrated component affects twice the global building balance: supporting the thermal plant (i.e. providing heat for final uses) and modifying the wall heat-transfer pattern (i.e. reducing thermal losses). In turn, the collector performance itself is influenced by the wall structure (back losses reduction). Present work proposes a method f…
An integrated approach based on Life Cycle Assessment and Thermoeconomics: Application to a water-cooled chiller for an air conditioning plant
2018
Abstract A large number of methods for energy systems analysis were developed in the last decades, aimed at acquiring an in-depth understanding of plant performances and enabling analysts to identify optimal design and operating conditions. In this work an integrated approach based on Life Cycle Assessment and Thermoeconomics is proposed as a method for assessing the exergo-environmental profile of energy systems. The procedure combines the capabilities of these two techniques, to account simultaneously for aspects related to thermodynamics of energy conversion processes and to the overall impacts along the plant life cycle related to other phases, i.e. from raw material extraction to the d…
Assessing the Energy-Saving Potential of a Dish-Stirling Concentrator Integrated into Energy Plants in the Tertiary Sector
2021
Energy consumed for air conditioning in residential and tertiary sectors accounts for a large share of global use. To reduce the environmental impacts burdening the covering of such demands, the adoption of renewable energy technologies is increasing. In this regard, this paper evaluates the energy and environmental benefits achievable by integrating a dish-Stirling concentrator into energy systems used for meeting the air conditioning demand of an office building. Two typical reference energy plants are assumed: (i) a natural gas boiler for heating purposes and air-cooled chillers for the cooling periods, and (ii) a reversible heat pump for both heating and cooling. For both systems, a dis…