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Currently, approximately 40% of the energy demand in the European Union (EU) is used in buildings and the energy demand for cooling and heating is increasing every year, so the energy efficiency of buildings represents a problem of increased interest and of extreme relevance. The article proposes, through the case study, the installation of a photovoltaic system for the production of electricity on the roofs of the buildings and the cooling and heating of the building using a water-to-water heat pump. Having the advantage of the location of the studied buildings on the banks of the river Bega in the town of Timisoara, the case study proposes the cooling of the spaces in the buildings in two variants, namely in the spring and autumn when the outside temperature is not very high using the river water directly ("free cooling"), and in the summer for the hot months, a water-to-water heat pump to cool the cooling agent to the parameters necessary to achieve a proper air conditioning. [ABSTRACT FROM AUTHOR]

The building sector is one of the largest final consumers of energy, especially for air conditioning, and research has shown that there is a great potential for energy savings in this sector. The performance of a chiller can vary significantly depending on system partial loads and evaporator and condenser operating temperatures. The condensers of water-only chillers take the heat of condensation from the refrigerant only through the sensible heat of the refrigerant, leading to significant water flows. The outside air temperature and the intensity of solar radiation directly influence the consumption of electricity on the chiller. Having available the values for the solar radiation intensity I [W/m2 ] and the outside air temperature te [⁰C], with the help of the proposed mathematical model, validated by experimental measurements, the optimal values for the minimum electricity consumption of the system are obtained, under the conditions which the chilled water temperature is 7/12⁰C and the indoor air temperature is 27⁰C [ABSTRACT FROM AUTHOR]

Underfloor heating systems ensure maximum comfort through optimal vertical temperature distribution, and the possibility of exact control and programming of the indoor climate. Used as a total heating source, the underfloor heating system will provide all the heat requirements of the space to be heated, provided that the external walls are properly insulated. In the study, two underfloor heating systems were analyzed using the dynamic simulation feature of the HTflux software. Following these simulations, temperature differences will be observed in front of the floor finish depending on the type of system used. The wet screed system heats up significantly faster and reaches a higher temperature by approximately 4.5% compared to the dry screed system. [ABSTRACT FROM AUTHOR]

As in 1973, the energy issue occupies the first page of the agenda of energy experts, social planners, politicians and, last but not least, consumers. The impact of renewable energy sources (wind and solar) on the energy infrastructure was analysed, while aiming to reduce carbon footprints. Demographic growth, urbanization, the targets imposed by Net Zero Emissions tend towards the massive forcing of energy towards renewable energy conversion and storage systems. [ABSTRACT FROM AUTHOR]

Considering the fact that the energy sector producing both thermal and electrical energy has a contribution to the increase of greenhouse gas emissions, the need to diversify energy production sources and equipment such as biomass power plants, installations that recover secondary fuel and thermal energy resources, solar installations and heat pumps is a major priority. The study carried out presents a solution for the integration of renewable energy sources (RES) for the production of electricity that will then be used both in the own thermal energy supply facilities, following that the surplus electricity will be used for the production of hot water that can be delivered in the district heating system. [ABSTRACT FROM AUTHOR]

In a residential building, the integration of thermal modules from the design phase can bring multiple benefits in terms of energy efficiency and thermal comfort. The article deals with a brief comparison between the traditional heating system and the decentralized system with apartment thermal modules by making the preparation of the thermal agent for heating and domestic hot water more efficient. The study was carried out following the new nZEB requirements regarding the obligation for all new buildings and those undergoing renovation to ensure a percentage of at least 30% from renewable sourcess. [ABSTRACT FROM AUTHOR]

Energy efficiency norms require effective insulation techniques for buildings in order to minimize energy consumption. The paper presents simulations, carried out throughout the year, regarding the efficiency of energy recovery units (ER) to ensure the quality of fresh indoor air. Indoor air energy recovery calculations were performed using plate and rotary heat exchangers in different operating scenarios. The evaluated parameters led to the stability of the optimization solutions in order to obtain a higher energy efficiency on the equipment. By comparing the obtained results, optimal measures and solutions were identified for energy efficiency in the operation of ER. [ABSTRACT FROM AUTHOR]

In an existing office building, integrating air-to-water heat pumps into a district heating system can bring multiple benefits in terms of energy efficiency and thermal comfort. The article deals with the implementation solution for the efficiency of district heating systems, exemplified by a case study related to an existing office building. The study was carried out following the multiple breakdowns that occurred in the thermal energy distribution system from the district heating company, as well as the interruption of thermal energy for long periods of time. [ABSTRACT FROM AUTHOR]

The increase in global temperature and the current energy context have brought the district heating system in Timișoara (partialy renovated) to the brink of collapse. Therefore, major investments and orientation towards the integration of renewable energy sources (RES) are required. The article analyzes, by exemplifying a case study, the integration of photovoltaic technologies at a heat point that supplies the buildings of the Faculty of Construction (CT) in Timișoara. The study was carried out with the help of Polysun software. The results obtained indicate a reduction in thermal and elctrical energy costs of 38.51% by installing a number of 1095 photovoltaic (PV) panels on the roof of 4 building bodies (ASPC, Deposit, CT and Metal). [ABSTRACT FROM AUTHOR]

In the context of the acceleration of the need to store and process data and digital telecommunications, which leads to an increase in global electricity consumption and greenhouse gas emissions, the need for research to find reliable, efficient, and cost-effective solutions to reduce energy consumption and the recovery of the residual heat produced by the data centres is an increasingly urgent one. The article presents aspects that refer to the recovery of residual energy from data centres and its use for the preparation of domestic hot water, but also for the preparation of the thermal agent necessary for heating installations in buildings and respectively modern heating systems, with the mention that the latter work at a low temperature regime. [ABSTRACT FROM AUTHOR]

Newly built houses are subject to requirements with high levels of energy performance including the creation of houses with zero energy consumption (passive houses) and respectively without carbon emissions. Building regulations, processes and control will need to be rethought in light of these ambitions and a development of performance guarantees in the construction sector.Many mandatory standards and rating systems for the energy efficiency of buildings have been developed globally, but those for passive houses are still voluntary, and for this reason there is little data on the performance of houses built to these standards. They have emerged as a promising approach to mitigating and solving many energy problems, and constructive visions and solutions and testing or demonstrating their feasibility are undoubtedly major steps in the process of solving the energy problem. [ABSTRACT FROM AUTHOR]

In the current context regarding energy sources’ problems, it is estimated that a high percentage of waste will be produced from photovoltaic panels, that will put pressure on the environment. Thus, the study focuses on downcycling them by incorporating them into mortars by six new recipes (R1, R2, R3, R4, R5 and R6) that replace the sand by integrating photovoltaic panels’ dust (PVd) and pieces of photovoltaic panels (PVp) (1/3 to 100% of the total amount). All samples were subjected to tensile bending, compression and an economic analysis and were compared with the control sample (R0). As a result of the experimental research, a change in the apparent density of the proposed samples was found, and a general improvement in all areas of testing. The obtained results show that used photovoltaic panels can constitute raw material for the creation of new construction materials. [ABSTRACT FROM AUTHOR]

Nuclear power is one of the most profitable, reliable, and low-carbon energies, so it can be seen as a source of the future. The article makes a comparative study between renewable technologies (photovoltaic, wind and nuclear) addressing both classical high-power (LR) and small-scale systems (SMRs) located in electrical energy consumption centres. The study highlights the advantages of nuclear energy in terms of land use, agricultural production, impact on wildlife and finally the possibility of cogeneration. In addition to these advantages, SMRs can provide charging stations for electric vehicles, which are also a solution of the near future [ABSTRACT FROM AUTHOR]

The paper presents a study on the efficiency of installing photovoltaic blinds in a didactic laboratory with large glased surfaces, in order to ensure the shading of the interior spaces and to avoid the use of air conditioners during warm periods of the year, as a contribution to the passive house concept. [ABSTRACT FROM AUTHOR]

The buildings sector is responsible for the largest percentage of total energy consumption, especially for heating and cooling. For this reason, the paper compares two heating/cooling systems (multisplit VRF and respectively chiller, central heating and fan coil units) for an office building. Energy consumption for heating/cooling, domestic hot water preparation and lighting, expressed in MWh/year, was analyzed. Following the simulation, the VRF air-conditioning system, which registers a global consumption of 70.23 MWh/year, compared to the system with a chiller, thermal plant and fan coil units, which registers a global consumption of 81.25 MWh/year, was found more advatageous. [ABSTRACT FROM AUTHOR]

The article analyses the variation of the vertically temperature gradient, in an industrial space heated with radiant tubes. Data monitoring was done with a workstation equipped with 5 high-performance temperature sensors. The temperature measurement was carried out in 5 distinct points inside/outside the production space, selected in different hypotheses, and a thermovision camera was used at the floor level. The values of the indoor air temperature measured at the level of the ankles, at the level of the work plane and at the level of the head of the people in the productive space fall within the normal limits. [ABSTRACT FROM AUTHOR]

The incontestable evidence of climate change and extreme weather events has brought the entire world to the brink of a red code alert, which determined the need to establish targets for limiting greenhouse gas emissions and the other actions that can be taken to solve them. The paper presents aspects of limiting the contribution of buildings to climate change through energy efficiency measures with an emphasis on the importance of the nZEB concept. The need to reduce the consumption of energy from fossil sources and increase the contribution of energy renewable sources is discussed, in a realistic context. [ABSTRACT FROM AUTHOR]

The paper aims to analyze the major influence of filters on the consumption of electricity in ventilation systems, especially in air treatment plants in accordance with ISO EN 16890. On-site measurements are made with the help of the air treatment plant within the HVAC laboratory, with a flow rate of 2700 m3/h, on two filters with dimensions of 287 mm x 592 mm x 500 mm. The results indicate an energy class C for the analyzed filter. As future directions of study for the achievement of energy efficiency within an HVAC system, simulation with the help of the TRNSYS software can be used, for different scenarios. [ABSTRACT FROM AUTHOR]

Considering the current energy context, with the increase in the price of natural gas and electricity, the use of renewable energy has recently had an increasing trend. In this sense, the article presents a case study for the energy efficiency of educational buildings, through the installation of photovoltaic systems and air-water heat pumps. The simulation was carried out with the help of the Polysun calculation program, analyzing the energy consumption of the ASPC building of the Faculty of Construction in Timișoara, in the existing situation and in the proposed efficiency stages. The results show that in the first stage of efficiency in which the photovoltaic PV system and the airwater heat pump are installed, a decrease in costs for the necessary thermal and electrical energy is achieved, by 42.36%. In the second stage, in which it is proposed to decrease the return/return temperature regime of the indoor installation from 60/40 ℃ to 40/30 ℃, the result is a decrease in the electricity consumption from the national network by 7.94%. [ABSTRACT FROM AUTHOR]

Given that water is an indispensable and valuable resource, the water shortage faced by some areas of the globe has recently attracted the attention of the European Environment Agency (EEA). For this reason, the paper deals with aspects regarding the possibility of using water from precipitation, taking into account, for the study, buildings from two rural localities adjacent to Timișoara (Giarmata and Moșnița Nouă). An analysis was carried out regarding the amount of drinking water that can be replaced in indoor sanitary installations with captured and stored water from precipitation. The amount of potable water that can be replaced was considered only for household needs such as: flushing toilets, washing clothes, watering green spaces and gardens and washing impervious spaces (lanes, yards, etc.) on the property. The study considered 5 stages of approach through which the quantity and quality of rainwater that can be collected, the technical solutions that can be implemented and the reduction of the amount of drinking water were evaluated, taking into account two consumption scenarios (reduced and increased). Based on the data obtained, it was concluded that for a low level of consumption, in the two buildings, the amount of water collected from precipitation fully covers the consumption of the household needs taken into account, and for the scenario of increased consumption, only 2 and 3 weeks of consumption remain uncorrelated which are the equivalent of a normal vacation period in which no consumption is recorded. In conclusion, the installation of rainwater storage systems is reliable for residential buildings, especially in rural localities where properties benefit from larger land areas. [ABSTRACT FROM AUTHOR]

One of the world’s topical issues is the necessity of energy consumption reduction in order to conserve less and less natural resources and protect the environment. The article deals with the need to develop the waste energy recovery solutions that reduce energy consumption among the industrial consumers. In order to identify the sources with recoverable potential and establish energy recovery solutions, thermography of the hot air and hot gas exhaust circuits from industrial technological facilities were performed, followed by monitoring the operation parameters and measuring the energy consumption. The energy consumption reduction is analyzed by comparative interpretations of the hourly consumption, before and after applying the optimal recovery solution. The analysis of the results revealed that the waste energy recovery during the technological facilities operation has, besides the economic benefit, also other positive energetic effects, technical and not at least ecological ones.

Due to the pressure that landfills have on the environment, the article deals with the possibility of recycling waste from abrasive water jet cutting machines (AWJCM) because this waste either takes the path of storage (abrasive sludge) or is discharged into public sewer systems (wastewater). Thus, for the abrasive sludge, two new mortar recipes were proposed, made by replacing fractions of sand with abrasive sludge. The series of cast samples R1 and R2 were subjected to mechanical tests and an increase in bulk density was found with the replacement of parts of the sand component with abrasive sludge, a decrease in mechanical tensile strength in bending and compression, which can be explained by the fact that wet abrasive sludge was used. Another line of research addressed the study of the possibility of reusing discharged wastewater. From this point of view, chemical analyzes were performed for two water samples on the basis of which it could be concluded that the recovered wastewater can be reused in the water supply installation of the abrasive water jet cutting machines. Based on the results obtained, it can be said that the resulting waste can be a raw material for the construction of building materials and can contribute to a considerable reduction in drinking water consumption. [ABSTRACT FROM AUTHOR]

The current context of climate change requires the efficiency of district heating systems. The article proposes the implementation of modernization solutions for district heating systems in order to reduce heat loss on the distribution system and implicitly CO2 emissions at the level of thermal agent production. The case study analyses the supply of the Forestry Technical College from Timisoara, which has a heat demand for the building of 1MW and is located at a distance of 1200m from the nearest thermal point. Simulations were performed for several efficiency stages of the central heating system, which before efficiency, operated without any control over the supply with thermal agent. The first stage of efficiency involves the transition from the uncontrolled continuous supply of the final consumer to an adjustable supply according to the thermal energy requirement, and the second stage represents the reduction of supply temperatures on the supply and return pipes from the high temperature regime (tt = 80°C and tr = 60°C), to an average temperature regime (tt = 60°C and tr = 40°C). [ABSTRACT FROM AUTHOR]

Given the current context regarding environmental pollution, in which conventional installations also participate, the aim of this article is to analyse whether photovoltaic systems are a viable solution to help solve this problem. Thus, the article analyses the way in which the electricity production of photovoltaic installations is influenced by the aging of the photovoltaic cells that make it up, but also by certain natural factors (water droplets, shading caused by clouds). Experimental measurements were performed on a new ZY-S100 thin-film photovoltaic panel and then on an aged one (7 years of operation) using an MI 3109 EurotestPV Lite METREL. When it comes to the main problem addressed in the paper, the influence of the aging of photovoltaic cells on the efficiency of the photovoltaic panels, the measurements indicated that the aged panel suffered a 25% decrease in efficiency in the seven years of operation, which comes to a decrease of 3.57% for each year. [ABSTRACT FROM AUTHOR]

Water consumption worldwide has increased considerably in recent decades and has a growing trend due to population growth in the coming years. Migration of the population from rural areas to urban areas will lead to problems arising from water insufficiency in crowded areas. Urban areas are oftentimes up to 8°F warmer than the surrounding rural area, creating “urban heat islands”. In densely populated areas where more water is consumed, an important consideration would be whether a part of the urban water requirement can be covered by rainwater harvesting. First, rainwater harvesting helps to conserve water by reducing the amount of water needed for toilet (and urinal) flushing, and outdoor watering. The article analyzes the water consumption averaged between years 2015 and 2017 (thermal power plants, humidifiers, and plumbing) for a 25- stories building located in Canada. Based on the analysis, it was found that the combined seasonal average for the spring and summer was 62% higher than the winter and fall seasons. By using rainwater instead of potable (drinking) water for these applications, homeowners can reduce their daily water use by approximately 30%. [ABSTRACT FROM AUTHOR]

In agreement with lasting development and ensuring a sustainable future for administrative territorial units (ATUs) in Romania, the article proposes measures to support the environment with positive effects on natural freshwater resources and consumption. The study presents the context, necessity, and justification for plumbing modification from buildings, focused on the reduction of drinking water consumption through the recovery, storage, and reuse of rainwaters. The analysis of climatic parameters, quality indicators of rainwater harvested, and the proposed technical solutions was performed to justify the usefulness and the necessity of implementing the solutions for recovering and reusing this resource. [ABSTRACT FROM AUTHOR]

The use of renewable energy sources (RES), which also includes waste biomass, is a current national and global concern for sustainable development by reducing greenhouse gas emissions (GHG). Partial replacement of fossil fuels with biomass is a possibility, together with other sources of nonpolluting energy production such as hydropower, wind, solar and geothermal, to reduce greenhouse gas emissions as the amount of CO2 resulting from the combustion of biomass is equal to that captured during its training. Optimizing waste biomass utilization technologies ensures GHG reduction. [ABSTRACT FROM AUTHOR]