Academic literature on the topic 'Building Energy Exchange'

Energy exchanges between buildings is affected by urban fabric. As a matter of fact, heat exchange between adjacent buildings is due to convective and radiative heat flows. The main parameters which influence these heat exchange mechanisms are due to climate conditions such as air temperatures/humidity, wind speed/direction and solar irradiance. Most building energy simulations are done on an independent single building with typical meteorological year (TMY). These TMY meteorological data cannot represent the state of the urban microclimate and rather ignores the microclimate influence on buildings adjacent to street canyons. However, solar radiation shading and reflection of the environment within the street canyons are important factors affecting the energy consumption of buildings. In this work, a building energy simulation tool is used to study the impact of multiple shortwave inter-reflections in an urban environment. A street canyon model validated in a previous work was modeled in TRNSYS in order to simulate the effects of the urban radiative trapping. An urban canyon with aspect ratio H/W=1 was chosen, with South-North orientation, with transparent/opaque surfaces ratio Atr/Aop=0.5 and 4 values (0.2, 0.4, 0.6, 0.8) of reflectance factor of the envelope surfaces. The goal is to characterize how solar absorption influence the urban energy requirements. The analysis was conducted for 3 cities in different climatic zones: Rome, Palermo and Krakow.

With the ever-increasing population and historic highest energy demand, the energy efficiency of buildings is becoming crucial. Architectural firms are moving from traditional Computer-Aided Design (CAD) to BIM. However, nearly 40% of the energy consumption is due to buildings. Therefore, there is a need to integrate BIM with Building Energy Modeling (BEM), which presents an innovative opportunity to demonstrate the potential of BIM to minimize energy consumption by integrating building information software with data from existing energy-efficient building automation systems (EBAS). BEM is a form of computational analysis that can be used in conjunction with BIM or Computer-Aided Engineering (CAE) systems. In this paper, an attempt has been made to explore the existing literature on BIM and BEM and identify the effect of the integration of BEM in BIM in the design phase of the project. A recent survey from the last ten years (2012 to 2023) was carried out on Google Scholar, Web of Science, Science Direct, and Scopus databases. Inclusion/exclusion criteria were applied, and papers were scrutinized. From the results, it can be observed that the convergence of BIM and BEM is found to be useful in practical applications; however, projects with short life cycles might not be suitable for this solution. Challenges exist in the interoperability tools which have restrictions on data exchange. Binary translation is found to be the most suitable candidate for data exchange. The analysis further showed that the most used program for integrating BIM/BEM is Green Building Studio developed by Autodesk to improve construction and operational efficiencies.

In order to solve the dynamic characteristics of fuel cell thermal energy in building equipment intelligent control system, this paper proposes the application research of building equipment intelligent control system in renewable energy thermal energy modelling. A cold water proton exchange membrane fuel cell cogeneration scheme was proposed. The heat produced by the installation is carried out by the cooling system, and the heat is exchanged between the heat exchanger and the hot water always heated in the heat exchanger. At the same time, a water tank is used to store hot water for heat recovery. Based on MATLsimulation coupling software platform, the simulation model of fuel cell cogeneration system was es?tablished, including reactor model, power system model, heat exchanger model, etc. The simulation model of fuel cell cogeneration system was built up, including the reactor model, power system model, and so on. The experimental results show that the system can achieve good response performance and anti-disturbance by using fuzzy PID controller to control and simulate the system. At the same time, the simulation results show that the optimal efficiency of the system in the power load is about 83%. In conclusion, it can meet the modern family?s thermal power demands and improve the power consumption.

Apply integrated approaches for the air exchange rate determination based on CO 2 concentration in educational and residential buildings of Ukraine. Methods. Taking into account variability of building's visitors and occupants operational and behavioral features experimental and calculated determination of the air exchange rate are considered. Results. Recommendations for providing comfort conditions in terms of air quality in the considered objects premises, recommendations on the premises operating conditions, ventilation schedule. Scientific novelty. The comprehensive approach to in-depth analysis of energy consumption has been developed, procedures for assessing the air quality and the level of air exchange in buildings have been improved taking into account the variability of operating conditions. The practical significance. Experimental studies of changes in CO 2 concentration were conducted in three schools, in higher education institution and in residential building. The research results allowed to establish the actual level of CO 2 concentration and air change rate under different operational and behavioral conditions in buildings during working hours, subject to comfortable conditions, and during non-use hours. The research results also help to determine the dynamics of changes in the studied factor over time under the building performance indicators influence. The obtained results allow to provide recommendations on ensuring the quality of indoor air exchange and on providing comfort working, studying and living conditions. The use of experimental and calculated air exchange rate values for various premises would allow to avoid in mathematical modeling the overestimation of the level of buildings energy consumption, which arises when standard air change rate values is using. So the obtained results allow to approximate more accurately the mathematical modeling results of buildings energy efficiency to the actual conditions and help to choose the optimal schedule for the building engineering networks managing considering comfort conditions with intermittent operation.

The heat exchanger can use shallow geothermal energy to provide regional heating and cooling demand in winter and summer. In this paper, a large-scale public building is taken as the example, and the energy system in the building is taken as the research object. Firstly, through the collection of geothermal drilling geographic information and geothermal data, the geothermal reserves and geothermal recoverable resources are evaluated. Secondly, the cooling and heating demand of the building is calculated by using HVAC simulation software. Then, the heat transfer capacity of a single pile is evaluated and the layout scheme of the underground heat exchange pile foundation of the building is given. The actual heating effect of the heat exchange pile foundation system is explored, and the heat transfer characteristics of heat exchange pile foundation under different working conditions are compared and analyzed. Finally, reasonable suggestions for the arrangement of heat exchange pile foundation are given.

“Net Zero-Energy Building” has become a popular catchphrase to describe the synergy between energy-efficient building and renewable energy utilisation to achieve a balanced energy budget over an annual cycle. Taking into account the energy exchange with a grid overcomes the limitations of energy-autonomous buildings with the need for seasonal energy storage on-site. Although the expression, “Net Zero-Energy Building,” appears in many energy policy documents, a harmonised definition or a standardised balancing method is still lacking. This paper reports on the background and the various effects influencing the energy balance approach. After discussing the national energy code framework in Germany, a harmonised terminology and balancing procedure is proposed. The procedure takes not only the energy balance but also energy efficiency and load matching into account.

Today, most countries in the world have mandatory regulations, more or less strict, regarding energy efficiency in buildings. However, a large percentage of the buildings already built were constructed under lax or non-existing regulations in this regard. Therefore, many countries are facing the energy refurbishment of their existing buildings to reduce their carbon footprint. Depending on ambient weather conditions where a building settles, its operation with respect to the achievement of maximum energy efficiency should usually be different. This happens in subtropical climates when, during the year and depending on the season, the building needs to conserve heat, evacuate it or even make an exchange with the outside to take advantage of favorable environmental conditions. This paper presents a complete methodology for conducting building energy efficiency refurbishments in subtropical climates in order to convert them into minimum energy buildings. The proposed methodology is illustrated by a case study in a dwelling that includes all the stages, from the analysis of the existing dwelling to the refurbishment works, showing the final results and the subsequent dwelling operation.

Tightness and energy efficiency are among the most important parameters of buildings. The airtightness of the building ensures a reduction in energy consumption for heating, especially for buildings with a large heating volume. Currently, Ukraine does not have a regulatory framework for determining the tightness of buildings. The article analyzes the international standard for determining the airtightness of buildings ISO 9972:2015 Thermal characteristics of buildings − Determination of air permeability of buildings − Method of fan injection. On the basis of the international standard, the methodical bases for determining the tightness of the building envelope have been improved, and the methodology for determining the tightness of the building envelope has been adapted for Ukraine. The article presents the methods of measuring the tightness of the building, the rules for preparing the building for measurements, as well as the calculation of air permeability parameters. This technique contains the principle of determining the parameters of tightness in the conditions of fan injection. The hermeticity of the building, or its air permeability, is expressed by the amount of air leakage in cubic meters per hour per square meter of the area of ​​the outer shell of the building when the building is affected by a pressure drop of the internal air of 50 Pa. During the test, the fan creates a pressure drop of 50Pa. A differential manometer is used to record the pressure difference between the pressure in the room and the external pressure. Using the formulas given in the article, the volume flow of air through the enclosing structures is calculated, and the air leakage rate is also calculated. Based on the determined parameters, the air exchange rate n50 and the air exchange rate q50 at the created pressure drop ∆p were calculated. The method of determining the energy efficiency class based on the n50 parameter has been improved. Based on the results of the calculations, we have the opportunity to determine the energy efficiency class based on the determined air exchange ratio.

The Italian territory is characterized by a big increase in energetic demand, especially for cooling, mainly related to climate change but also to the poor quality of a consistent construction sector, such as the suburban 1960–1980 building stock. At the same time, the cost of fuel and electricity due to the recent war events forces us to find alternative solutions to save energy in buildings. This study proposes building envelope passive design strategies to improve the energy efficiency of residential buildings in the Mediterranean climate, which is typical of the Italian territory. The main purpose is to provide an overview of potential passive measures to improve the energetic quality of construction in response to the above-mentioned issues and consequently to the increasing restrictions of energy regulations (passive buildings and NzeB). A categorization of passive measures is provided by exploring three different passive behaviors: heat reduction, heat gain, and heat protection. Specific energy-efficient measures for building retrofit are investigated according to this classification, including solar greenhouses, natural ventilation techniques, and radiative, convective, and conductive heat transfer through opaque and transparent envelopes. As the building envelope is mainly responsible for heating exchange and accounts for 50% of the overall energy balance, it is concluded that the “ad hoc” design of building envelopes can significantly improve the overall thermal performance of residential buildings.

Modern results of Ukrainian buildings energy analysis show that 30-50% of the energy for heating goes to heat the supply air, and that is the largest share in the building energy balance. In terms of energy consumption, efficiency of the air exchange mode largely depends on occupancy schedule and air distribution in time and space. The application of air exchange schedule approach makes more sense in case when individual heating control is carried out. Therefore, during occupied hours, the comfortable ventilation level can be ensured, and, during unoccupied hours, it can be reduced to a minimum. According to the results of the study, the use of intermittent air exchange mode in the studied apartment on weekdays, leads to decrease in energy consumption compared to constant air exchange at the level of upper values of the ventilation schedule. In terms of energy efficiency, the use of the constant air change rate from ASHRAE Std 62 is the most efficient approach. In terms of indoor air quality and concentration of CO2 and VOCs, the scheduled air exchange approach with increased air change rates (from EN 16798) during occupied hours is more efficient. Therefore, the use of required and experimental air change rate values to create the hourly schedules allows to define more precisely a building energy consumption and to choose an optimal operation schedule for building engineering systems to provide thermal comfort and indoor air quality during occupied hours.

In 2013, Stockholms Hamnar began a development project for Värtahamnen, one of Stockholms most important harbors, and also decided to build a new ferry terminal that is better suited to meet the increasing capacity demand. The new terminal will feature a borehole storage that will be used to cover the building’s heating and cooling demands. The boreholes have already been drilled and currently the construction of the building is being planned. The overall objective of this project is to study the new terminal and its borehole storage regarding certain input parameters (such as internal heat gains and the U-value of windows) that affect the building’s annual heating and cooling demands, as well as long-term temperature of the borehole storage. To do this, two modeling programs are used: IDA ICE and EED (Earth Energy Designer). The project focuses on three main parts. Part one is a sensitivity analysis of internal loads and construction specific parameters that shows how a variation in these affects the heating and cooling demands. To accomplish this, several models are created and simulated in IDA ICE. In part two, the long-term ground temperature is studied for two of the models analyzed in part one. This is done in both IDA (through a new borehole module) and EED, followed by a comparison of these results. The last part presents the possible amount of free cooling that can be taken from the ground. This estimation is made through simulations in EED, using altered load profiles of the two previously mentioned models. Additionally, this part covers the effects of a changed borehole configuration (number of boreholes, depth, layout, etc.). The results of the first part (the sensitivity analysis) show that there is a rather large variation in annual heating and cooling demands depending on what approach is used for estimating a reasonable amount of internal loads. One way to do this is to first determine the maximum possible load in each zone and then, when simulating the annual energy demand, reduce the total load in the whole building by a certain factor. Another approach is to, from the start of the building modeling, more accurately try to estimate the average amount of internal loads in each zone. In the second part, due to unbalanced load profiles for both analyzed models, the temperature of the borehole storage will increase over time if there is no limitation of the amount of cooling taken from the ground. The results of IDA generally agree with those of EED. In the last part of the project it is shown that a thermally more favorable borehole installation could increase the relative amount of free cooling from the ground, compared to the current installation.

Requirements regarding efficient energy use and reduction in CO2 emissions are becoming increasingly strict. The building sector accounts for a large part of CO2 emissions and the potential for reductions within this sector should be considerable.This thesis is a continuation of the author's project thesis. The main focus is to improve the earlier model emphasizing the modeling of the interactions between the leisure home building and the ground. The goal is to develop a prototype of a leisure home where sanitary installations are kept frost proof throughout the year without the use of primary energy sources or electricity, minimizing net CO2 emissions. The building envelope is constructed of poorly insulated log walls. The sanitary installations are placed in a thermally insulated internal zone, and an active solar heating system is developed to transfer heat into the ground in this internal zone. The intention is to store the heat, transferred to the internal zone during sunny periods, in a thermal mass under the cabin. This would then passively arise during cold periods, maintaining frost proof conditions. The leisure home is planned to be located in the southern mountain regions of Norway. Different simulation tools were considered for modeling the leisure home and its energy system. The dynamic simulation tool ESP-r was chosen, and an improved model from the project thesis was developed. Different methods and theories concerning how the solar heating system and the ground could be modeled have been studied. The interactions between the building and the ground were modeled by implementing a new basement zone for the leisure home, and defining a BASESIMP configuration as boundary conditions for the surfaces adjacent to the ground. BASESIMP performs quasi 3-dimensional calculations for the heat transfer between the building and the ground. Since the heat storage is not taken into account in the BASESIMP configuration, the storage is represented in the ground construction; the basement floor of the inner zone. The solar heating system is represented in a control loop. The control loop injects electric heat into the basement floor for a given period each day. The electric data is based on solar radiation data, and the time intervals for when heat is injected into the floor are determined from when solar radiation is available in the day. Climate data from Östersund, Sweden has been used as an approximation as there was no available climate file for the southern mountain regions of Norway. Different system parameters have been changed to investigate the influence they have on the temperature conditions in the internal zones throughout the year. The internal zones maintain much more stable temperatures throughout the year than the outer zones. This shows that isolating the frost proof zones in the leisure home, represent a major advantage in the design process. The ground construction in the basement floor of the inner zone has been modeled as a thermal mass with high density and high specific heat capacity. This dense thermal mass is modeled to account for the whole area under the cabin. A south facing solar collector with an area of 4 m2 and an inclination of 70 ° indicates that the temperature in the internal zones stays above 4.2 °C throughout the year, subject to the given ground conditions and without collecting heat during May until August. The delivered energy to the ground construction in the basement floor of the inner zone for a year under the given conditions and with a collector efficiency of 45 % turned out to be 878 kWh.Heat transfer from the ground into the internal zone turned out to have a significant heat contribution in cold periods. Results also showed a noticeable potential for seasonal storage of the energy extracted from the solar heating system.For further studies, the interactions between the heat storage and the surrounding ground should be studied in a 3-dimensional conduction program. Insulation regarding snow should also be implemented in a future model to study the effect of extra insulation on the ground surface.

Pile heat exchangers are expected to make a significant contribution to meeting UK and EU renewable energy and carbon dioxide reduction targets. However, design for the thermal capacity of pile heat exchangers has to date been largely based on methods developed for borehole heat exchangers. Piles have a much smaller aspect (length to diameter) ratio than boreholes and consequently their thermal behaviour is different in a number of important ways. This thesis explores these differences and makes recommendations for improved assessment of pile heat exchanger thermal capacity. Traditionally vertical heat exchanger design assumes separation of the thermal effects in the ground and in the pile. A transient temperature response function is used to assess temperature changes in the ground and a steady state resistance is applied to the pile concrete. In this thesis existing approaches to temperature response functions are critically assessed for use with thermal piles. It is important to take into account the larger pile diameter, which causes increased temperature changes in the short term. In the long term, the shorter pile length will result in reduced temperature changes as steady state is reached more quickly. Simple 2D numerical modelling has been carried out and the results used to derive a new method for determining pile thermal resistance. However, for large diameter piles, the time taken for the pile to reach steady state suggests that the use of a constant thermal resistance in design is not always appropriate. In these cases it is recommended that a transient temperature response function is used to assess the response of the ground and the concrete together. The applicability of short duration thermal response testing for pile heat exchangers has been examined. Modelling and case study data has shown that the technique is only reliable for piles of 300mm diameter or less. For the special case of large diameter piles with centrally placed heat transfer pipes then it is possible to use the test to determine the thermal conductivity of the pile concrete, but not pile thermal resistance.

There is a large potential in making the residential and service sector more energy efficient and the first step towards achieving a more efficient use of energy is to implement an energy audit. In this study a property with an approximate area of 8 000 m2, consisting of a main building and three building extensions from different eras has been examined. The main building and its extensions were built in different stages and the first one in the early 20th century and some parts of the last building extension were modified at the time that the examination was carried out. This indicates that there is a vast energy savings potential in the property and an energy audit was performed. The main aim of the study was to examine where the energy was being used and where energy could be saved. Energy saving measures has been suggested together with a calculated approximate energy decrease and payback period. The total energy savings potential for the measures is approximately 146 MWh. The energy audit showed that a large amount of electricity was being used during non-work hours and that energy was lost through the building envelope. The electricity use during non-work hours was examined during the night walk, however, it is suggested to carry out further examinations regarding the property’s vast electricity use during non-work hours. To add loose wool in the roof of B2 has an energy savings potential of 33 000 kWh/year. Another measure is to clean the heat exchangers, this measure has an energy savings potential of 26 000 kWh/year. Also it is suggested to optimize the operational hours for the lighting by implementing presence control and to decrease the energy use for ventilation by cleaning the heat exchangers. Further examinations that would improve the study would be to do measurements of the electricity and temperatures to get a better understanding of the buildings energy use. Also to model the building in a simulation tool would give a calculated energy loss that is more like the actual energy loss of the building and make the results more reliable.

Syfte: Syftet med arbetet är att bidra till att fastighetsägare fortsatt ska kunna förvalta, driva och bruka gamla kulturhistoriskt viktiga hus även i framtiden. Metod: De metoder som valts för att uppnå målet är dokumentanalys, litteraturstudier och fallstudie. Resultat: Kulturhistoriskt viktiga byggnader behöver energieffektiviseras för att de ska kunna hållas i bruk och existera. Det går att genomföra energieffektiviserande åtgärder utan att skada byggnadens kulturvärde. Åtgärder som fönsterbyte, tilläggsisolering och byte av ventilationssystem bör väljas beroende på husets karaktär. Tilläggsisolering och fönsterbyte är effektiva åtgärder för att minska energiförbrukningen av gamla kulturhistoriskt viktiga byggnader, men riskerar ofta att förvanska byggnadens karaktär. Ventilationssystemsbyte kan innebära mindre ändringar av byggnaden men är en relativt dyr investering. Konsekvenser: Ändringar i en befintlig byggnad kommer dock alltid att påverka dess konstruktion, men det betyder inte att byggnadens kulturhistoriska värde förvanskas. Begränsningar: Beräkningar kommer endast att utföras för ett referensobjekt, stadsbibliotek i Tidaholm. Det beräknade resultatet kommer vara specifikt för denna byggnad, eftersom resultatet varierar med byggnaders olika egenskaper. Däremot kan lösningarna tillämpas på flera objekt. Det finns flera olika energieffektiviserande åtgärder men i denna rapport utreds tilläggsisolering, fönsterbyte och ventilationsbyte. Nyckelord: Energieffektivisering, kulturhistoriskt viktiga byggnader, värmeväxlare, Boverkets byggregler, ventilation.
Purpose: The purpose of the work is to help municipalities continue to manage, operate and use old historic houses in the future. Method: The methods chosen to achieve the objective is document analysis, literature studies and case study. Findings: Culture heritage buildings needs to get more energy efficient, so they can be kept in use and existence. It is possible to implement energy efficiency measures without damaging the building's cultural value. Measures like window replacement, insulation and replacement of ventilation systems should be selected depending on the character of the house. Insulation and window replacement are effective measures to reduce the energy consumption of old historically important buildings, but often risk distorting the character of the building. Ventilation system replacement can involve minor changes to the building but is a relatively expensive investment. Implications: Changes in an existing building will always affect its construction, but it does not mean that the building's heritage value is distorted. Limitations: Calculations will only be performed for a reference object, library in Tidaholm. The calculated result will be specific for this building, since the outcome varies with buildings and their different characteristics. However, the solutions can be applied to multiple objects. There are several energy efficiency measures, but this report will only involve insulation, window replacement and ventilation changes. Keywords: Energy efficiency, historically important buildings, heat exchanger, building regulations, ventilation.

In the last years smart buildings topic has received much attention as well as Building Information Modelling (BIM) and interoperability as independent fields. Linking these topics is an essential research target to help designers and stakeholders to run processes more efficiently. Working on a smart building requires the use of Innovation and Communication Technology (ICT) to optimize design, construction and management. In these terms, several technologies such as sensors for remote monitoring and control, building equipment, management software, etc. are available in the market. As BIM provides an enormous amount of information in its database and theoretically it is able to work with all kind of data sources using interoperability, it is essential to define standards for both data contents and format exchange. In this way, a possibility to align research activity with Horizon 2020 is the investigation of energy saving using ICT. Unfortunately, comparing the Architecture Engineering and Construction (AEC) Industry with other sectors it is clear how in the building field advanced information technology applications have not been adopted yet. However in the last years, the adoption of new methods for the data management has been investigated by many researchers. So, basing on the above considerations, the main purpose of this thesis is investigate the use of BIM methodology relating to existing buildings concerning on three main topics: • Smart data management for architectural heritage preservation; • District data management for energy reduction; • The maintenance of highrises. For these reasons, data management acquires a very important value relating to the optimization of the building process and it is considered the most important goal for this research. Taking into account different kinds of architectural heritage, the attention is focused on the existing and historical buildings that usually have characterized by several constraints. Starting from data collection, a BIM model was developed and customized in function of its objectives, and providing information for different simulation tests. Finally, data visualization was investigated through the Virtual Reality(VR) and Augmented Reality (AR). Certainly, the creation of a 3D parametric model implies that data is organized according to the use of individual users that are involved in the building process. This means that each 3D model can be developed with different Levels of Detail/Development (LODs) basing on the goal of the data source. Along this thesis the importance of LODs is taken into account related to the kind of information filled in a BIM model. In fact, basing on the objectives of each project a BIM model can be developed in a different way to facilitate the querying data for the simulations tests. The three topics were compared considering each step of the building process workflow, highlighting the main differences, evaluating the strengths and weaknesses of BIM methodology. In these terms, the importance to set a BIM template before the modelling step was pointed out, because it provides the possibility to manage information in order to be collected and extracted for different purposes and by specific users. Moreover, basing on the results obtained in terms of the 3D parametric model and in terms of process, a proper BIM maturity level was determined for each topic. Finally, the value of interoperability was arisen from these tests considering that it provided the opportunity to develop a framework for collaboration, involving all parties of the building industry.

This study aims to rationalize the consumption of thermal energy in residential buildings by recovering heat from wastewater inside the building before entering the central sewage network outside the building, by conducting an analytical study for a residential tower in Syria to find out the coverage percentage of the heat energy recovered from wastewater for the heating and domestic hot water loads needed for the tower, and calculating the percentage of reduction in carbon dioxide (CO2) gases. It is a simple technology as the thermal recovery system consists of three main components, which are in order: a wastewater tank, heat exchangers, and a heat pump. The research begins with an introduction that consists of the importance of wastewater and the waste heat energy it carries. After that, there are some case studies, research problem, its importance, the aim of the research, and finally the research methodology. In the first chapter, we talked about the concept of heat recovery from wastewater in general, methods of heat recovery, and the most important advantages and disadvantages of this process. It also includes an identification of the main parts used in this technology and how it works, especially the exchangers and the heat pump. This chapter also addresses the problem of forming a layer of biofilms on the surface of heat exchangers from the wastewater side and the most important methods used to treat it. We move on to the second chapter, in which we review the most important facilities for heat recovery from wastewater that have been viewed. Then comes the third chapter in which the heat recovery process was conducted for a nine storey residential tower in Syria, each floor has four apartments, where we first calculated the rate of wastewater flow for the entire tower, and we proposed a heat recovery system (physical model) inside the tower. Then the mathematical equations for heat recovery and the solution of these equations were developed based on some necessary assumptions needed in the solution process to know the most important results desired in this field. It also included the calculation of the coverage ratio of the heat energy recovered from the wastewater for the domestic hot water and heating loads, as well as the calculation of the mass and percentage of the reduction of carbon emitted to the atmosphere. Then simple economic feasibility was also conducted in this chapter to know the daily financial savings as a result of using this technology. The research ends with the most important conclusions and future research that have been reached and the conclusion of the research. The most important results show that the average coverage percentage of heat energy recovered from wastewater for heating load in residential buildings ranges between [30-56%]. It was also found that the average coverage percentage of heat energy recovered from wastewater for domestic hot water load ranges between [65-100%].

There is global effort to reduce the emission of greenhouse gases that causes global climate change, of which significant percentage is related to buildings. Uses of passive and low-energy strategies for indoor thermal environmental control are being explored by researchers to reduce the operational energy consumption in bUildings. One of these options is the use of thermal mass of the ground as a heat source or heat sink for cooling and heating of indoor spaces in bUildings. Earth-air heat exchanger (EAHX) is a subterranean ventilation system that can be used to pre-coollpre-heat building ventilation air supply. Due to the ground's thermal mass, the daily fluctuation of ambient extremes is dampened with increasing depth below the ground surface. Therefore soil temperature at 1 m depth and below is always lower than ambient temperature in summer and higher than ambient temperature in winter. The application of EAHX and knowledge of their performance is scarce under UK climatic and soil conditions. This research therefore aims to evaluate the potential of using EAHX in the UK for cooling buildings in summer. Critical literature review has been undertaken on the performance of EAHX in different climatic conditions and the various approaches to the thermal analysis of EAHX. It reveals that the system has potential for building cooling applications in a variety of conditions. A standalone simulation tool has been developed using the Transient System Simulation Environment (TRNSYS). Building models using different mechanical ventilation strategy have also been developed to enable integrated evaluation of the performance of EAHX on indoor thermal comfort conditions and building cooling loads. Data of climatic and soil parameters required for the thermal analysis of EAHX have been determined for different regions in the UK. Integrated thermal simulations of EAHX system have been conducted using the developed building models and the determined soil and climate conditions. Monitoring data from an existing project incorporating EAHX have been analysed and results have been discussed. Parametric study of EAHX has been carried out for three locations, representing the regional climate span of the UK, in order to evaluate the range of thermal performance of the system. Data of various performance indicators have been established to provide the necessary information for the evaluation of the system potential in different locations. This research has established the thermal performance and the characteristics of the important parameters for the design of EAHX system in the UK. The outcomes are significant in contributing to a better understanding of the system's thermal behaviour and in predicting the thermal performance for building cooling application. As a future work, based upon the data generated by this research, there is a need to develop a full database of the performance data for different configurations of EAHX and at different locations around the country. There is also a need for integrated design tool to evaluate the dynamic thermal performance of EAHX system when integrated with other ventilation strategies.

Heating, Ventilating and Air Conditioning Systems (HVAC) are not only one of the most energy consuming components in buildings but also contribute to green house gas emissions. As a result often environmental design strategies are focused on the performance of these systems. New HVAC technologies such as Geothermal Heat Pump systems have relatively high performance efficiencies when compared to typical systems and therefore could be part of whole-building performance design strategies.

In collaboration with the Virginia Tech Corporate Research Center, Inc., this research studies the energy consumption and cost benefits of the Geothermal Heat Pump System that has been integrated and operated in the KnowledgeWorks I and II buildings located on the Virginia Tech campus.

The purpose of this thesis is to understand the energy and cost benefits of the Geothermal Heat Pumps System when compared to the conventional package variable air volume (VAV) with hot water coil heating and air-source heat pump systems using computer simulation and statistical models. The quantitative methods of building energy performance and life-cycle cost analyses are applied to evaluate the results of simulation models, the in-situ monitoring data, and the associated documents. This understanding can be expanded to the higher level of architectural systems integration.
Master of Science

This diploma thesis is focused on nearly zero energy buildings, which are a mandatory part of construction of the buildings in Czech republic after 2020. It also deals with HVAC and its design as part of these buildings. The theoretical part deals with legal and technical regulations and possible savings in HVAC systems. The computational part is focused on two solution of HVAC systems in given object. The project part is about the given object, which is otevřená zahrada Brno. This building was founded by Nadace Partnerství s.r.o.. This third part of diploma thesis deals with the quality of indoor microclimate and evaluation of the heat recovery system effiency, which is applied in local HVAC unit.

The 8-volume set contains the Proceedings of the 25th ECOS 2012 International Conference, Perugia, Italy, June 26th to June 29th, 2012. ECOS is an acronym for Efficiency, Cost, Optimization and Simulation (of energy conversion systems and processes), summarizing the topics covered in ECOS: Thermodynamics, Heat and Mass Transfer, Exergy and Second Law Analysis, Process Integration and Heat Exchanger Networks, Fluid Dynamics and Power Plant Components, Fuel Cells, Simulation of Energy Conversion Systems, Renewable Energies, Thermo-Economic Analysis and Optimisation, Combustion, Chemical Reactors, Carbon Capture and Sequestration, Building/Urban/Complex Energy Systems, Water Desalination and Use of Water Resources, Energy Systems- Environmental and Sustainability Issues, System Operation/ Control/Diagnosis and Prognosis, Industrial Ecology.

AbstractIn response to the problems of high energy consumption, high maintenance costs, and large space occupation of traditional dust removal equipment, this work utilizes TRIZ theory to innovate and invent a prefabricated wall that automatically circulates air to achieve dust removal function. The wall includes three parts: a solar thermal module, an air circulation dust removal module, and a building solid waste regeneration material insulation module. It uses solar energy to provide power, drive air circulation exchange, and achieve the application of clean energy to reduce dust in the factory building, The effect of reducing summer room temperature and low-carbon heating in winter.

AbstractHumanity in our days is fighting with climate change effects and the depletion of natural resources. In this direction, the adoption of sustainable and circular practices is considered vital and in most cases is prescribed by regulations. The construction sector is responsible for massive amounts of energy consumed during the extraction of raw materials, the production of building materials, the construction phase, the operating phase of the buildings, and also during their demolition and end-of-life. The latter one already gathers the scientific community’s interest with the efforts being focused on efficient Construction and Demolition Waste (CDW) management solutions. Meanwhile, Building Information Modelling (BIM), as a storage medium of information about all building components, offers various advantages on a building’s optimum design and operation, allowing information exchange among all involved stakeholders. Although many studies demonstrate the effectiveness of BIMs in reducing construction waste for new buildings, there is not extensive research on how BIMs can contribute to CDW reduction for an existing building. In this review study, the existing studies addressing BIM integration on CDW management are analyzed, pointing out the advantages that this strategy offers on reducing CDW and managing them efficiently, increasing reuse and recycle rates, and promoting circularity. The main challenges this approach presents, mainly attributed to the difficulty of gathering the required information with the appropriate accuracy about an existing building, are extensively discussed, along with future research needs, necessary for a further enhancement of this technique.

Studying the temperature regimes affecting the durability of the metal wall of heat exchanger pipes helps identify ways to enhance efficiency in heat exchange processes. One of the key factors determining the temperature regime of the pipe wall is the heat transfer. One of the main factors contributing to an increase in heat transfer is the intensification of heat exchange.

Rapid depletion of natural resources and increased environmental degradation demand a vigorous scrutiny of accepted design and construction methods. For more than ten years, New York City has promoted energy efficiency policies—including PlaNYC and the Greener, Greater Buildings Plan—that will radically reshape the education of architects toward energy performance in buildings, reduction of emissions, and the efficient use of resources. Our series of undergraduate studies investigates the relationship between the building form and energy performance, using form-finding algorithms based on solar radiation to shape mid-rise housing typologies for New York City. Currently funded by the Institute of Design and Construction Foundation, we have been exploring the important environmental design opportunities that exist within building envelopes, particularly in residential buildings that are responsible for most of the greenhouse gas (GHG)emissions and power consumption. By integrating and extending current solar technologies such as photovoltaic (PV) and solar thermal (ST) for the predominantly vertical infrastructure of the city, this research targets innovative building mass and surface strategies that are highly energy efficient, generateon-site renewable energy, and produce a new vocabulary for sustainable construction. As part of the initiative, we have also formed an international exchange program between our two institutions to share content and expertise.

<p>The controlling of the building climate requires an immense energy consumption worldwide. In modern buildings, the heating energy amount can be reduced into reasonable level by the use of building insulation and low u-value facade parts. In most countries the energy needed for building cooling is a significant amount of the total building energy consumption. At office buildings the necessary cooling energy often exceeds the consumed heating energy. Therefore modern building may use a variety of shading systems to reduce the input of solar radiation into the rooms. Beside manually operated systems especially electronically operated ones seem to be the future standard in buildings.</p><p>Despite their huge comfort and efficiency these electronically operated systems are often limited to higher standard buildings and wealthier regions. Therefore this paper describes as intermediate results of an ongoing research project several concepts of the integration of energy autonomous shading and ventilation systems. All of them base on the use of temperature sensitive shape memory alloy as actuator for the moving of mechanical components. They do not need any electrical energy or electrical components, like controllers, motors or infrastructure. The concept is demonstrated in various applications from shading blinds, shading lamellas, night cooling ventilation or forced ventilation for necessary room air exchange.</p><p>Promising main applications, as night cooling or shading lamellas are investigated and demonstrated in life- size mock-ups.</p>

This paper deals with the Off-Grid Zero Emissions Building (OGZEB), a project undertaken by the Sustainable Energy Science & Engineering Center (SESEC) at Florida State University (FSU). The project involves the design, construction and operation of a completely solar-powered building that achieves LEED-NC (Leadership in Energy and Environment Design-New Construction) platinum certification. The resulting 1000 square foot building will be partitioned such that 750 square feet will be a two bedroom, graduate student style flat with the remaining 250 square feet serving as office space. This arrangement will allow the building to serve as an energy efficient model for campus designers in student living and office space. The building will also serve as a prototype for developing and implementing cutting edge, alternative energy technologies in both residential and commercial settings. For example, hydrogen will be used extensively in meeting the energy needs of the OGZEB. In lieu of high efficiency batteries, the excess electricity produced by the building’s photovoltaic (PV) panels will be used to generate hydrogen via water electrolysis. The hydrogen will be stored on-site until needed for either generating electricity in a Proton Exchange Membrane (PEM) fuel cell stack or combusted in natural gas appliances that have been modified for hydrogen use. Although commercial variants already exist, a highly efficient water electrolysis device and innovative PEM fuel cell are currently under development at SESEC and both will be implemented into the OGZEB. The use of hydrogen in modified natural gas appliances, such as an on-demand hot water heater and cook top, is unique to the OGZEB.

Latin America and the Caribbean overcame significant economic challenges in 2023 and exceeded growth expectations thanks to the strong macroeconomic fundamentals it laid in recent years. The region was able to cut inflation through large interest rate hikes and unwind steep spending increases it had undertaken due to COVID-19a marked departure from previous crises where expansionary measures proved stubborn to reverse. To build on this success, countries now face additional challenges: lowering interest rates without triggering significant capital outflows, exchange rate depreciation, and an increase in inflation; reducing fiscal imbalances due to higher global interest rates in a politically charged context; and the daunting task of implementing far-reaching reforms to tackle low productivity and set the course for long-term growth. As countries chart their path forward, they can capitalize on their rich natural endowments-from renewable energy sources to minerals and food-to grow their economies on the road toward net-zero emissions. The 2024 Latin America and Caribbean Macroeconomic Report analyzes the opportunities and challenges facing the region as it embarks on this journey.

Higher education institutions play a crucial role in fostering innovation, research, and knowledge transfer that directly impact the attainment of the SDGs. Postgraduate education, in particular, provides a unique opportunity to train and equip the next generation of leaders, researchers, and professionals with the necessary skills, knowledge, and interdisciplinary perspectives required to address complex global challenges. The concept of the resource nexus emphasizes the interconnectedness of different resources (e.g., water, energy, food, materials) and the importance of adopting a holistic approach to sustainable development. By promoting collaborations and partnerships between the Global South and North, we can facilitate knowledge exchange, capacity building, mutual learning and technology transfer, thus creating a positive ripple effect across regions and addressing common sustainability challenges.

The North East of Scotland is at the forefront of the global energy transition. With the transformation of the UK’s energy sector over coming decades, the lives of communities and workers in the North East will be directly affected as we collectively transition to a Net Zero economy. A Just Transition refers to a fair distribution of the burdens and benefits as society and the economy shifts to a sustainable low-carbon economy. It calls for action on providing decent green jobs, building community wealth, and embedding participation. While it is a well-established concept in the academic literature and in policy there is a notable lack of approaches and data on measuring progress towards a Just Transition. In Scotland, with Just Transition planning underway, there are calls for clarity by the Scottish Parliament, Just Transition Commission, and many stakeholders on how to evaluate progress in a place-based context. The project ‘Just Transition for Workers and Communities in Aberdeen and Aberdeenshire’ brought together an interdisciplinary team from the University of Aberdeen Just Transition Lab to identify and collate the relevant evidence, and engage with a range of local stakeholders to develop regional Just Transition indicators. Previous work on this project produced a Rapid Evidence Assessment on how the oil and gas industry has shaped our region and what efforts and visions have emerged for a Just Transition. Based on the findings and a stakeholder knowledge-exchange event, we have developed a set of proposed indicators, supported by data and/or narrative, for a transition in Aberdeen and Aberdeenshire across four themes: 1) Employment and skills, 2) Equality and wellbeing, 3) Democratic participation, and 4) Community empowerment, revitalisation and Net Zero. Some of the indicators are compiled from national/local data sets, including data on jobs and skills, fuel poverty or greenhouse gas emissions. Other indicators require further data collection and elaboration, but nevertheless represent important aspects of Just Transition in the region. These include workers’ rights protection, community ownership, participation and empowerment. We propose four narrative scenarios as springboards for further dialogue, policy development, investment and participation on Just Transition in Aberdeen and Aberdeenshire. Indicators, as proxies for evaluating progress, can be used as decision support tools, a means of informing policy, and supporting stakeholder dialogue and action as we collectively progress a Just Transition in the North East. There are no shortcuts on a way to a Just Transition. Progress towards achieving it will require a clear articulation of vision and objectives, co-developed with all stakeholders around the table. It will require collaboration, trust, difficult conversations, and compromise as we develop a collective vision for the region. Finally, it will require strong political will, substantive policy and legal reform, public and private investment, and building of social licence as we collectively build a Net Zero future in the North East.

Public procurement of goods and services contributes to about 15% of global greenhouse gas emissions. In the EU, public purchasing represents 15% of its GDP, acting as a major influencer on the market through the products and services acquired by governments from the local to national levels. The public sector has a role to play in leveraging this purchasing power to achieve the best societal value for money, particularly as we scramble to bend the curve of our planet’s warming. Globally, the construction and transport sectors each represent about 12% of government procurements’ GHG emissions. Furthermore, these sectors’ decarbonization efforts demand profound and disruptive technological shifts. Hence, prioritizing these sectors can make the greatest impact towards reducing the environmental footprint of the public sector and support faster decarbonization of key emitting industries. Meanwhile, the EU committed to achieving 55% reduction in GHG emissions by 2030 compared to 1990 levels. Drastic emissions reductions are needed at an unprecedented speed and scale to achieve this goal. Green Public Procurement (GPP) is the practice of purchasing goods and services using environmental requirements, with the aim of cutting carbon emissions and mitigating environmental harm throughout the life cycle of the product or service. While the EU and many of its Member States alike have recognized GPP as an important tool to meet climate goals, the formalization of GPP requirements at the EU level or among local and national governments has been fragmented. We call for harmonization to achieve the consistency, scale and focus required to make GPP practices a powerful decarbonization tool. We surveyed the landscape of GPP in the EU, with a focus on construction and road transport. Through interviews and policy research, we compiled case studies of eight Member States with different profiles: Sweden, the Netherlands, France, Germany, Estonia, Poland, Spain and Italy. We used this information to identify solutions and best practices, and to set forth recommendations on how the EU and its countries can harmonize and strengthen their GPP policies on the path toward cutting their contributions to climate change. What we found was a scattered approach to GPP across the board, with few binding requirements, little oversight and scant connective tissue from national to local practices or across different Member States, making it difficult to evaluate progress or compare practices. Interviewees, including policy makers, procurement experts and procurement officers from the featured Member States, highlighted the lack of time or resources to adopt progressive GPP practices, with no real incentive to pursue it. Furthermore, we found a need for more awareness and clear guidance on how to leverage GPP for impactful societal outcomes. Doing so requires better harmonized processes, data, and ways to track the impact and progress achieved. That is not to say it is entirely neglected. Most Member States studied highlight GPP in various national plans and have set targets accordingly. Countries, regions, and cities such as the Netherlands, Catalonia and Berlin serve as beacons of GPP with robust goals and higher ambition. They lead the way in showing how GPP can help mitigate climate change. For example, the Netherlands is one of the few countries that monitors the effects of GPP, and showed that public procurement for eight product groups in 2015 and 2016 led to at least 4.9 metric tons of avoided GHG emissions. Similarly, a monitoring report from 2017 showed that the State of Berlin managed to cut its GHG emissions by 47% through GPP in 15 product groups. Spain’s Catalonia region set a goal of 50% of procurements using GPP by 2025, an all-electric in public vehicle fleet and 100% renewable energy powering public buildings by 2030. Drawing from these findings, we developed recommendations on how to bolster GPP and scale it to its full potential. In governance, policies, monitoring, implementation and uptake, some common themes exist. The need for: • Better-coordinated policies • Common metrics for measuring progress and evaluating tenders • Increased resources such as time, funding and support mechanisms • Greater collaboration and knowledge exchange among procurers and businesses • Clearer incentives, binding requirements and enforcement mechanisms, covering operational and embedded emissions With a concerted and unified movement toward GPP, the EU and its Member States can send strong market signals to the companies that depend on them for business, accelerating the decarbonization process that our planet requires.

1.1 Macroeconomic summary Economic recovery has consistently outperformed the technical staff’s expectations following a steep decline in activity in the second quarter of 2020. At the same time, total and core inflation rates have fallen and remain at low levels, suggesting that a significant element of the reactivation of Colombia’s economy has been related to recovery in potential GDP. This would support the technical staff’s diagnosis of weak aggregate demand and ample excess capacity. The most recently available data on 2020 growth suggests a contraction in economic activity of 6.8%, lower than estimates from January’s Monetary Policy Report (-7.2%). High-frequency indicators suggest that economic performance was significantly more dynamic than expected in January, despite mobility restrictions and quarantine measures. This has also come amid declines in total and core inflation, the latter of which was below January projections if controlling for certain relative price changes. This suggests that the unexpected strength of recent growth contains elements of demand, and that excess capacity, while significant, could be lower than previously estimated. Nevertheless, uncertainty over the measurement of excess capacity continues to be unusually high and marked both by variations in the way different economic sectors and spending components have been affected by the pandemic, and by uneven price behavior. The size of excess capacity, and in particular the evolution of the pandemic in forthcoming quarters, constitute substantial risks to the macroeconomic forecast presented in this report. Despite the unexpected strength of the recovery, the technical staff continues to project ample excess capacity that is expected to remain on the forecast horizon, alongside core inflation that will likely remain below the target. Domestic demand remains below 2019 levels amid unusually significant uncertainty over the size of excess capacity in the economy. High national unemployment (14.6% for February 2021) reflects a loose labor market, while observed total and core inflation continue to be below 2%. Inflationary pressures from the exchange rate are expected to continue to be low, with relatively little pass-through on inflation. This would be compatible with a negative output gap. Excess productive capacity and the expectation of core inflation below the 3% target on the forecast horizon provide a basis for an expansive monetary policy posture. The technical staff’s assessment of certain shocks and their expected effects on the economy, as well as the presence of several sources of uncertainty and related assumptions about their potential macroeconomic impacts, remain a feature of this report. The coronavirus pandemic, in particular, continues to affect the public health environment, and the reopening of Colombia’s economy remains incomplete. The technical staff’s assessment is that the COVID-19 shock has affected both aggregate demand and supply, but that the impact on demand has been deeper and more persistent. Given this persistence, the central forecast accounts for a gradual tightening of the output gap in the absence of new waves of contagion, and as vaccination campaigns progress. The central forecast continues to include an expected increase of total and core inflation rates in the second quarter of 2021, alongside the lapse of the temporary price relief measures put in place in 2020. Additional COVID-19 outbreaks (of uncertain duration and intensity) represent a significant risk factor that could affect these projections. Additionally, the forecast continues to include an upward trend in sovereign risk premiums, reflected by higher levels of public debt that in the wake of the pandemic are likely to persist on the forecast horizon, even in the context of a fiscal adjustment. At the same time, the projection accounts for the shortterm effects on private domestic demand from a fiscal adjustment along the lines of the one currently being proposed by the national government. This would be compatible with a gradual recovery of private domestic demand in 2022. The size and characteristics of the fiscal adjustment that is ultimately implemented, as well as the corresponding market response, represent another source of forecast uncertainty. Newly available information offers evidence of the potential for significant changes to the macroeconomic scenario, though without altering the general diagnosis described above. The most recent data on inflation, growth, fiscal policy, and international financial conditions suggests a more dynamic economy than previously expected. However, a third wave of the pandemic has delayed the re-opening of Colombia’s economy and brought with it a deceleration in economic activity. Detailed descriptions of these considerations and subsequent changes to the macroeconomic forecast are presented below. The expected annual decline in GDP (-0.3%) in the first quarter of 2021 appears to have been less pronounced than projected in January (-4.8%). Partial closures in January to address a second wave of COVID-19 appear to have had a less significant negative impact on the economy than previously estimated. This is reflected in figures related to mobility, energy demand, industry and retail sales, foreign trade, commercial transactions from selected banks, and the national statistics agency’s (DANE) economic tracking indicator (ISE). Output is now expected to have declined annually in the first quarter by 0.3%. Private consumption likely continued to recover, registering levels somewhat above those from the previous year, while public consumption likely increased significantly. While a recovery in investment in both housing and in other buildings and structures is expected, overall investment levels in this case likely continued to be low, and gross fixed capital formation is expected to continue to show significant annual declines. Imports likely recovered to again outpace exports, though both are expected to register significant annual declines. Economic activity that outpaced projections, an increase in oil prices and other export products, and an expected increase in public spending this year account for the upward revision to the 2021 growth forecast (from 4.6% with a range between 2% and 6% in January, to 6.0% with a range between 3% and 7% in April). As a result, the output gap is expected to be smaller and to tighten more rapidly than projected in the previous report, though it is still expected to remain in negative territory on the forecast horizon. Wide forecast intervals reflect the fact that the future evolution of the COVID-19 pandemic remains a significant source of uncertainty on these projections. The delay in the recovery of economic activity as a result of the resurgence of COVID-19 in the first quarter appears to have been less significant than projected in the January report. The central forecast scenario expects this improved performance to continue in 2021 alongside increased consumer and business confidence. Low real interest rates and an active credit supply would also support this dynamic, and the overall conditions would be expected to spur a recovery in consumption and investment. Increased growth in public spending and public works based on the national government’s spending plan (Plan Financiero del Gobierno) are other factors to consider. Additionally, an expected recovery in global demand and higher projected prices for oil and coffee would further contribute to improved external revenues and would favor investment, in particular in the oil sector. Given the above, the technical staff’s 2021 growth forecast has been revised upward from 4.6% in January (range from 2% to 6%) to 6.0% in April (range from 3% to 7%). These projections account for the potential for the third wave of COVID-19 to have a larger and more persistent effect on the economy than the previous wave, while also supposing that there will not be any additional significant waves of the pandemic and that mobility restrictions will be relaxed as a result. Economic growth in 2022 is expected to be 3%, with a range between 1% and 5%. This figure would be lower than projected in the January report (3.6% with a range between 2% and 6%), due to a higher base of comparison given the upward revision to expected GDP in 2021. This forecast also takes into account the likely effects on private demand of a fiscal adjustment of the size currently being proposed by the national government, and which would come into effect in 2022. Excess in productive capacity is now expected to be lower than estimated in January but continues to be significant and affected by high levels of uncertainty, as reflected in the wide forecast intervals. The possibility of new waves of the virus (of uncertain intensity and duration) represents a significant downward risk to projected GDP growth, and is signaled by the lower limits of the ranges provided in this report. Inflation (1.51%) and inflation excluding food and regulated items (0.94%) declined in March compared to December, continuing below the 3% target. The decline in inflation in this period was below projections, explained in large part by unanticipated increases in the costs of certain foods (3.92%) and regulated items (1.52%). An increase in international food and shipping prices, increased foreign demand for beef, and specific upward pressures on perishable food supplies appear to explain a lower-than-expected deceleration in the consumer price index (CPI) for foods. An unexpected increase in regulated items prices came amid unanticipated increases in international fuel prices, on some utilities rates, and for regulated education prices. The decline in annual inflation excluding food and regulated items between December and March was in line with projections from January, though this included downward pressure from a significant reduction in telecommunications rates due to the imminent entry of a new operator. When controlling for the effects of this relative price change, inflation excluding food and regulated items exceeds levels forecast in the previous report. Within this indicator of core inflation, the CPI for goods (1.05%) accelerated due to a reversion of the effects of the VAT-free day in November, which was largely accounted for in February, and possibly by the transmission of a recent depreciation of the peso on domestic prices for certain items (electric and household appliances). For their part, services prices decelerated and showed the lowest rate of annual growth (0.89%) among the large consumer baskets in the CPI. Within the services basket, the annual change in rental prices continued to decline, while those services that continue to experience the most significant restrictions on returning to normal operations (tourism, cinemas, nightlife, etc.) continued to register significant price declines. As previously mentioned, telephone rates also fell significantly due to increased competition in the market. Total inflation is expected to continue to be affected by ample excesses in productive capacity for the remainder of 2021 and 2022, though less so than projected in January. As a result, convergence to the inflation target is now expected to be somewhat faster than estimated in the previous report, assuming the absence of significant additional outbreaks of COVID-19. The technical staff’s year-end inflation projections for 2021 and 2022 have increased, suggesting figures around 3% due largely to variation in food and regulated items prices. The projection for inflation excluding food and regulated items also increased, but remains below 3%. Price relief measures on indirect taxes implemented in 2020 are expected to lapse in the second quarter of 2021, generating a one-off effect on prices and temporarily affecting inflation excluding food and regulated items. However, indexation to low levels of past inflation, weak demand, and ample excess productive capacity are expected to keep core inflation below the target, near 2.3% at the end of 2021 (previously 2.1%). The reversion in 2021 of the effects of some price relief measures on utility rates from 2020 should lead to an increase in the CPI for regulated items in the second half of this year. Annual price changes are now expected to be higher than estimated in the January report due to an increased expected path for fuel prices and unanticipated increases in regulated education prices. The projection for the CPI for foods has increased compared to the previous report, taking into account certain factors that were not anticipated in January (a less favorable agricultural cycle, increased pressure from international prices, and transport costs). Given the above, year-end annual inflation for 2021 and 2022 is now expected to be 3% and 2.8%, respectively, which would be above projections from January (2.3% and 2,7%). For its part, expected inflation based on analyst surveys suggests year-end inflation in 2021 and 2022 of 2.8% and 3.1%, respectively. There remains significant uncertainty surrounding the inflation forecasts included in this report due to several factors: 1) the evolution of the pandemic; 2) the difficulty in evaluating the size and persistence of excess productive capacity; 3) the timing and manner in which price relief measures will lapse; and 4) the future behavior of food prices. Projected 2021 growth in foreign demand (4.4% to 5.2%) and the supposed average oil price (USD 53 to USD 61 per Brent benchmark barrel) were both revised upward. An increase in long-term international interest rates has been reflected in a depreciation of the peso and could result in relatively tighter external financial conditions for emerging market economies, including Colombia. Average growth among Colombia’s trade partners was greater than expected in the fourth quarter of 2020. This, together with a sizable fiscal stimulus approved in the United States and the onset of a massive global vaccination campaign, largely explains the projected increase in foreign demand growth in 2021. The resilience of the goods market in the face of global crisis and an expected normalization in international trade are additional factors. These considerations and the expected continuation of a gradual reduction of mobility restrictions abroad suggest that Colombia’s trade partners could grow on average by 5.2% in 2021 and around 3.4% in 2022. The improved prospects for global economic growth have led to an increase in current and expected oil prices. Production interruptions due to a heavy winter, reduced inventories, and increased supply restrictions instituted by producing countries have also contributed to the increase. Meanwhile, market forecasts and recent Federal Reserve pronouncements suggest that the benchmark interest rate in the U.S. will remain stable for the next two years. Nevertheless, a significant increase in public spending in the country has fostered expectations for greater growth and inflation, as well as increased uncertainty over the moment in which a normalization of monetary policy might begin. This has been reflected in an increase in long-term interest rates. In this context, emerging market economies in the region, including Colombia, have registered increases in sovereign risk premiums and long-term domestic interest rates, and a depreciation of local currencies against the dollar. Recent outbreaks of COVID-19 in several of these economies; limits on vaccine supply and the slow pace of immunization campaigns in some countries; a significant increase in public debt; and tensions between the United States and China, among other factors, all add to a high level of uncertainty surrounding interest rate spreads, external financing conditions, and the future performance of risk premiums. The impact that this environment could have on the exchange rate and on domestic financing conditions represent risks to the macroeconomic and monetary policy forecasts. Domestic financial conditions continue to favor recovery in economic activity. The transmission of reductions to the policy interest rate on credit rates has been significant. The banking portfolio continues to recover amid circumstances that have affected both the supply and demand for loans, and in which some credit risks have materialized. Preferential and ordinary commercial interest rates have fallen to a similar degree as the benchmark interest rate. As is generally the case, this transmission has come at a slower pace for consumer credit rates, and has been further delayed in the case of mortgage rates. Commercial credit levels stabilized above pre-pandemic levels in March, following an increase resulting from significant liquidity requirements for businesses in the second quarter of 2020. The consumer credit portfolio continued to recover and has now surpassed February 2020 levels, though overall growth in the portfolio remains low. At the same time, portfolio projections and default indicators have increased, and credit establishment earnings have come down. Despite this, credit disbursements continue to recover and solvency indicators remain well above regulatory minimums. 1.2 Monetary policy decision In its meetings in March and April the BDBR left the benchmark interest rate unchanged at 1.75%.

The Central Asia Regional Economic Cooperation (CAREC) Program recognizes the unique climate impacts experienced by its member countries. Its vision for climate action aims to help coordinate the region’s efforts while acknowledging individual needs. The vision seeks to support countries in preserving their essential functions, identities, and structures while incorporating learning on how best to manage the impacts of energy transformation in all sectors. Concrete steps toward collective action include agenda setting, investments for projects with regional significance, policy coordination, capacity building and research, knowledge exchange, and technology transfer.