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The energy challenges of overcoming climate change and economic and global political crises require not only the increased integration of renewable energies but also an optimisation of energy generation and use and, as a result, a reduction in energy consumption in various sectors. Thermal energy consumption in buildings in particular accounts for a significant proportion of final energy consumption. With respect to commercial buildings, a central problem in optimising the system settings is the lack of or only limited information about the actual room temperatures as well as the comfort requirements and temperature perception of the users in the rooms on the one hand and the operational management and settings specified by the facility management, for example, the heating curves of the heating circuits, on the other. The aim here is to create a bidirectional flow of data and information so that the compromise between the necessary room temperatures and the comfort of the users and the most energy-efficient operational management possible can be achieved. In this context, the paper presents a developed and tested web platform that makes it possible to optimise the operation of the system technology, particularly the heating system in the building, from an energy point of view and to involve the building user (e.g., office employees) and to pass on information to the facility management, thus pursuing a holistic approach. In the associated Living Lab project (called ComfortLab), it was possible to obtain over 6500 votes on temperature perception and combine this with building operation and the parameters relevant to facility management. This made it possible to bridge the gap between user requirements and room temperatures on the one hand and energy consumption and the inlet temperature of the heating system and supply circuits on the other. The use of the platform makes it possible to optimise the setpoint specification, specifically the inlet temperature of individual heating circuits, considering both regular building operation at times of presence and the setting of weekend and night setback times. The results show a diversified picture regarding temperature perception and possible room temperature reductions of several degrees Celsius and energy savings in the double-digit percentage range. [ABSTRACT FROM AUTHOR]

Abstract Sustainable and climate-friendly space heating and cooling is of great importance for the energy transition. Compared to conventional energy sources, Aquifer Thermal Energy Storage (ATES) systems can significantly reduce greenhouse gas emissions from space heating and cooling. Hence, the objective of this study is to quantify the technical potential of shallow low-temperature ATES systems in terms of reclaimable energy in the city of Freiburg im Breisgau, Germany. Based on 3D heat transport modeling, heating and cooling power densities are determined for different ATES configurations located in an unconsolidated gravel aquifer of varying hydrogeological subsurface characteristics. High groundwater flow velocities of up to 13 m d−1 cause high storage energy loss and thus limit power densities to a maximum of 3.2 W m−2. Nevertheless, comparison of these power densities with the existing thermal energy demands shows that ATES systems can achieve substantial heating and cooling supply rates. This is especially true for the cooling demand, for which a full supply by ATES is determined for 92% of all residential buildings in the study area. For ATES heating alone, potential greenhouse gas emission savings of up to about 70,000 tCO2eq a−1 are calculated, which equals about 40% of the current greenhouse gas emissions caused by space and water heating in the study areas’ residential building stock. The modeling approach proposed in this study can also be applied in other regions with similar hydrogeological conditions to obtain estimations of local ATES supply rates and support city-scale energy planning.

In order to understand the application of artificial intelligence in the control system of cold and hot energy station, the author proposes a research based on artificial intelligence control in the control system of cooling and heating energy station. The author first introduces artificial intelligence technology on the basis of heating and precision heating, relies on the "Internet plus" and IoT platform, applies indoor temperature measurement technology, intelligent control and information docking technology, and establishes a heating system based on artificial intelligence technology. This system has improved the level of enterprise management, promoted the further development of heating and intelligent energy conservation, reduced energy consumption, reduced pollution, and achieved the need for precise heating of the pipe-line network. Secondly, combined with the application case of a district, this district is selected as the application pilot to describe the role and effect of this system in the Hydronics. The experimental results indicate that the heat consumption of the residential area is 27.07 W/m2, while the heat consumption of the comparison residential area is 28 W/m2. Through indoor temperature measurement, it was found that the average indoor temperature of the comparison residential area is 22 °C. Therefore, the application of artificial intelligence heating systems has improved the thermal comfort of residents, bringing users a high quality heating experience while relatively reducing energy consumption. The intelligent application of the Hydronics can more accurately grasp the heating situation, timely and efficiently adjust the heating scheme, achieve heating balance, and improve the utilization efficiency of heat sources. At the same time, it can also effectively improve the troubleshooting ability of the hydronics, prevent safety risks, improve management efficiency, and will certainly provide more powerful support for the energy-saving society and environment-friendly society. [ABSTRACT FROM AUTHOR]

This work theoretically studies the capability of using vortex tubes to provide the necessary heating and cooling energies required by a typical direct-contact membrane distillation (MD) process. The vortex tube generates a temperature separation that can supply the membrane distillation process with sufficiently hot feed and cold permeate with a temperature difference as large as 70 °C. Several structures integrating vortex tubes and MD with and without heat recovery and cascading are proposed and their respective performances are assessed and compared. A maximum distillate production of 38.5 kg/h was obtained at an inlet air pressure of 9 bar, cold air mass ratio of 0.7, and air-to-water mass ratio of 9. The corresponding energy consumption was found to be 25.9 kWh/m3. The production rate can be increased up to 75.2 kg/h and the specific energy consumption can be reduced to 13.3 kWh/m3 when three MD stages were connected in series using the same single vortex tube at the same operating conditions. It is found that the cold fraction plays an important role in the balance between heating and cooling operations. In addition, cold fraction values smaller than 0.7 should be avoided to prevent water from freezing inside the membrane. [ABSTRACT FROM AUTHOR]

Solar application in buildings is limited by available installation areas. The performance of photovoltaic (PV) and solar collectors are compared in meeting the heating and cooling demand of a residential house using 100% solar energy through TRNSYS modelling of five systems that use air source heat pump and seasonal energy storage as optional assisting technologies. The results show that in a large scale, the PV working with air source heat pump is more efficient than the solar collector system. However, the photovoltaic/thermal (PV/T) is the most spatially efficient with an energy capacity of 551 kWh/m2, 10.6% higher than that of the PV. Compared with the air source heat pump heating system using grid power, using solar energy regardless of system formats can reduce emission by 72% in a lifetime of 20 years. Solar energy can become cost-effective if the utility price is increased to above 0.7 CNY/kWh. The results can help in renewable planning in the studied climate. [ABSTRACT FROM AUTHOR]

Green buildings, i.e. low-energy and environmentally-friendly buildings, are highly demanded for optimizing the energy consumption and reducing the Green House Gas (GHG) Emissions. In this study, energy consumption of a residential building is analyzed in the hot and dry climate of Kashan, Iran. This is done based on the criteria of green buildings, using the Design Builder software. Several approaches are presented and discussed for the analysis, including the installing a thermal insulation layer, using external shadings and interior curtains, regulating the optimal comfort temperature, using an economizer, regulating the optimal domestic heat water (DHW) temperature, and installing photovoltaic panels. We investigate heating and cooling energies, as well as the total amount of energy saving in different conditions of the building. The results demonstrate that using the presented strategies leads to 67% and 39.3% reductions in electricity and gas consumption, respectively. Also, the carbon dioxide emissions are decreased 50.5% as a result of implementing the proposed methods.

The decarbonisation strategy of the building sector, which accounts for 24% of national greenhouse gas (GHG) emissions, is important to achieve climate neutrality in Korea by 2050. In this study, a bottom-up model and four scenarios were developed for examining scenarios for the decarbonisation of the residential building by 2050. A comparative analysis of energy consumption, GHG emissions, and investment cost was performed. The result showed that building energy performance improvement and heating fuel electrification are key measures for decarbonisation. We concluded that an investment of KRW 6.2 trillion per year would be required to achieve the 2050 decarbonisation scenario. Policy strategies were proposed for increasing investment in accelerating building retrofit, mandating zero-energy building (ZEB), and prohibiting gas boilers.

Abstract More than 30% of Germany’s final energy consumption currently results from thermal energy for heating and cooling in the building sector. One possibility to achieve significant greenhouse gas emission savings in space heating and cooling is the application of aquifer thermal energy storage (ATES) systems. Hence, this study maps the spatial technical potential of shallow low-temperature ATES systems in Germany. Important criteria for efficient ATES operation considered in this assessment encompass suitable hydrogeological conditions, such as aquifer productivity and groundwater flow velocity, and balanced space heating and cooling demands. The latter is approximated by the ratio of heating and cooling degree days, which is incorporated as a time-dependent criterion to also evaluate the impact of climate change on the ATES potential. The hydrogeological and climatic criteria are combined within a spatial analysis revealing that, regarding the upcoming decades, about 54% of the investigated German area are very well or well suitable for ATES applications, largely concentrating on three regions: the North German Basin, the Upper Rhine Graben and the South German Molasse Basin. Considering time-dependent climatic conditions, the very well or well suitable areas will increase by 13% for the time period 2071–2100. This is mostly caused by a large relative area increase of the very well suitable regions due to an increasing cooling demand in the future. The sensitivity of the very well and well suitable regions to the criteria weightings is relatively low. Accounting for existing water protection zones shows a reduction of the country-wide share of very well or well suitable areas by around 11%. Nevertheless, the newly created potential map reveals a huge potential for shallow low-temperature ATES systems in Germany.

The decarbonisation strategy of the building sector, which accounts for 24% of national greenhouse gas (GHG) emissions, is important to achieve climate neutrality in Korea by 2050. In this study, a bottom-up model and four scenarios were developed for examining scenarios for the decarbonisation of the residential building by 2050. A comparative analysis of energy consumption, GHG emissions, and investment cost was performed. The result showed that building energy performance improvement and heating fuel electrification are key measures for decarbonisation. We concluded that an investment of KRW 6.2 trillion per year would be required to achieve the 2050 decarbonisation scenario. Policy strategies were proposed for increasing investment in accelerating building retrofit, mandating zero-energy building (ZEB), and prohibiting gas boilers. [ABSTRACT FROM AUTHOR]

More than 30% of Germany's final energy consumption currently results from thermal energy for heating and cooling in the building sector. One possibility to achieve significant greenhouse gas emission savings in space heating and cooling is the application of aquifer thermal energy storage (ATES) systems. Hence, this study maps the spatial technical potential of shallow low-temperature ATES systems in Germany. Important criteria for efficient ATES operation considered in this assessment encompass suitable hydrogeological conditions, such as aquifer productivity and groundwater flow velocity, and balanced space heating and cooling demands. The latter is approximated by the ratio of heating and cooling degree days, which is incorporated as a time-dependent criterion to also evaluate the impact of climate change on the ATES potential. The hydrogeological and climatic criteria are combined within a spatial analysis revealing that, regarding the upcoming decades, about 54% of the investigated German area are very well or well suitable for ATES applications, largely concentrating on three regions: the North German Basin, the Upper Rhine Graben and the South German Molasse Basin. Considering time-dependent climatic conditions, the very well or well suitable areas will increase by 13% for the time period 2071–2100. This is mostly caused by a large relative area increase of the very well suitable regions due to an increasing cooling demand in the future. The sensitivity of the very well and well suitable regions to the criteria weightings is relatively low. Accounting for existing water protection zones shows a reduction of the country-wide share of very well or well suitable areas by around 11%. Nevertheless, the newly created potential map reveals a huge potential for shallow low-temperature ATES systems in Germany. [ABSTRACT FROM AUTHOR]

In the residential sector in R. Macedonia, most of the existing buildings are energy inefficient with high heating energy consumption, fossil fuels and direct use of electrical energy as a heating source. A lack of information and high Capital Expenditures (CAPEX) are identified as main reasons for the low attractiveness of district heating (wherever available) and heat pumps respectively. Therefore, the aim of this paper is through techno-economic assessment of different heat sources and technologies to provide well-founded answers that would create a good basis for future decisions in this sector. As the key performance is used Levelized Cost of Energy (LCOE) considering climate and economic conditions in R. Macedonia. The analysis is conducted for a reference heating area of 70m2 with specific heating energy consumption of 70 kWh/m2a, cooling energy 20 kWh/m2a and 30 kWh/m2a for domestic hot water (DHW). The considered technologies are heat pump air-water and air-air, electric boiler, natural gas boiler, wood pellet boiler and district heating. Sensitivity analysis is performed to assess the extend to which the change in investment, electricity and fuel prices affect the LCOE and economic viability. Results indicate that district heating has lowest LCOE, followed by system with air conditioners. [ABSTRACT FROM AUTHOR]

Tunnel geothermal systems hold the potential to promote decarbonization of the building heating and cooling sector. They can be integrated into existing infrastructure, resulting in low additional costs. In addition, these systems have large contact areas with the ground leading to larger heat fluxes. However, tunnel geothermics is relatively unknown and rarely used. Thus, the objective of this study is to provide an overview of the two primary tunnel geothermal system types as well as their application and potential. Open hydrothermal systems use the tunnel drainage water as a heat source, whereas closed absorber systems harness the heat flux from the subsoil and the warm tunnel interior via heat exchangers. The evaluation of the global application of existing and planned tunnel geothermal systems shows that all open systems are currently located in mountainous regions with a thick rock overburden. In contrast, closed absorber systems are mostly installed in urban tunnel infrastructures. The spatial distribution of geothermal tunnel systems has a focus in central Europe with Switzerland, Germany and Austria being the countries with the highest number of installed systems. Finally, this study also presents a brief summary of existing methods to determine the geothermal potential of tunnels. [ABSTRACT FROM AUTHOR]

An exemplary construction project developed in a commune close to Constanta, Romania, aims to build wooden houses for families with low income. The study focuses on their energy performance, aiming to determine simple technical solutions for the improvement of energy efficiency. The original house is a duplex ground floor building. The energy assessment was performed in accordance with the Romanian methodology for the original house, for the reference one and for a variant of the original house whose ground floor is insulated. The study showed that appropriate insulation of the ground floor which covers 30% of the thermal envelope area results in a heating energy saving of 17%. Furthermore, the original horizontal duplex was compared to its similar vertical version (ground floor and one storey) which is more compact, at the same heated volume and the same heated area. The reference vertical version saves 3% of heating energy.

• Causal relationship among waste generation, R&D intensity, and economic growth. • Panel vector error correction model is employed to study the causal relationship. • Regions of old and new EU countries are compared. • Bidirectional causality exists between waste generation and economic growth. • Bidirectional link among waste generation, heating energy, and R&D intensity. The relationship between economic growth and waste generation is a major global concern. Previous studies provided no conclusive evidence as to the causality between these two concepts, which can be attributed to at least two problems. First, R&D intensity is increasingly recognized as being an important determinant of environmental quality. Second, the regional level is considered to be important for the implementation of waste management policies, as regions and municipalities, among others, are responsible for separate collection systems and for establishing and managing treatment facilities. Previous studies failed to reflect the heterogeneity of the regions, which may lead to biased results. To address these problems, the panel vector error correction model was employed to examine the Granger causality in EU regions. The results provide empirical support for the existence of short- and long-run bidirectional causality between waste generation and economic growth in EU regions. A bidirectional link among waste generation, heating energy, and R&D intensity was also observed. The policy implication is that traditional economic development policies are not enough to reduce waste generation in EU regions. Economic tools, such as charges and incentives, and eco-innovation policies should be introduced to promote the region's shift towards a circular economy model. [ABSTRACT FROM AUTHOR]

An exemplary construction project developed in a commune close to Constanta, Romania, aims to build wooden houses for families with low income. The study focuses on their energy performance, aiming to determine simple technical solutions for the improvement of energy efficiency. The original house is a duplex ground floor building. The energy assessment was performed in accordance with the Romanian methodology for the original house, for the reference one and for a variant of the original house whose ground floor is insulated. The study showed that appropriate insulation of the ground floor which covers 30% of the thermal envelope area results in a heating energy saving of 17%. Furthermore, the original horizontal duplex was compared to its similar vertical version (ground floor and one storey) which is more compact, at the same heated volume and the same heated area. The reference vertical version saves 3% of heating energy. [ABSTRACT FROM AUTHOR]

Apartments account for over 60% of total residential buildings and consume a significant portion of primary energy in South Korea. Various energy efficiency measures have been implemented for both new apartment constructions and existing apartment retrofits. Old apartment structures have poor thermal performances, resulting in a high energy consumption. The South Korean government initiated retrofitting projects to improve the energy efficiency in old apartments. Apartment owners typically replace old windows with high-performance windows; however, there is still a demand for better and more innovative retrofit methods for a highly improved energy efficiency. This paper proposes an advanced double-skin façade (DSF) system to replace existing balcony windows in old apartments. Considering the cold climate conditions of Seoul, South Korea, it mainly discusses heating energy savings. Three case models were developed: Base-Case with existing apartment, Case-1 with typical retrofitting, and Case-2 with the proposed DSF system. The EnergyPlus simulation program was used to develop simulation models for a floor radiant heating system. A typical gas boiler was selected for lowtemperature radiant system modeling. The air flow network method was used to model the proposed DSF system. Five heating months, i.e., November to March, and one representative day, i.e., January 24, were selected for detailed analysis. The main heat loss areas consist of windows, walls, and infiltration. The results reveal that the apartment with the DSF retrofit saves 38.8% on the annual heating energy compared to the Base-Case and 35.2% compared to Case-1. [ABSTRACT FROM AUTHOR]

In this study, the optimum insulation thickness was calculated for the heating season for external walls in the different directions of a building. For this reason, a building used for housing in Istanbul, Turkey was taken as model. The indoor and outdoor temperatures, along with the interior and exterior surface temperatures of the building's external walls, were continuously measured using thermocouples and recorded in four different directions throughout the year. The effects of solar radiation, which vary based on the direction, were assessed for the heat transfer through the external walls. The results of this study indicate that the optimum insulation thickness for the north, south, west, and east facing walls should be 6.47, 2.87, 6.97, and 6.98 cm, respectively, based on the differences in the amount of solar radiation exposure of the walls in the different directions. The optimum insulation thickness of the building's external wall was calculated as 5.25 cm, regardless of its direction. An economic analysis of the thermal insulation cost was conducted using the P1-P2 method, and then the payback periods were calculated. The heating energy consumption of the building designed using the optimum insulation thicknesses, as identified separately based on the direction, decreased by 17%, compared to the present building with 3 cm of thermal insulation. [ABSTRACT FROM AUTHOR]

This paper emphasizes the experimental and numerical study of new cob mixes used for insulation and load bearing wall elements. The experimental study provides complete datasets of thermal properties of the new walling materials, using cob with density ranging from 1107 kg/m3 to 1583 kg/m3 for structural walls and less than 700 kg m−3 for insulation walls. Various mixes of French soils and fibres (reed, wheat straw, hemp shiv, hemp straw, and flax straw) with different water contents are studied. The lowest average thermal conductivity is obtained for the structural cob mix prepared of 5% wheat straw and 31% of water content. The insulation mix, prepared with 25% reed and 31% water content, has the lowest thermal conductivity. Investigation of diffusivity, density, and heat capacity shows that, when thermal conductivity is lower than 0.4 W m−1 K−1, the decrease in cob density leads to better insulation values and higher heat capacity. Little variation is noticed regarding the density and heat capacity for cob mixes with thermal conductivity higher than 0.4 W m−1 K−1. Furthermore, the non-uniformity of local thermal conductivity and heat losses through the samples is due mainly to the non-uniform distribution of fibres inside the mixes inducing an increase in heat loss up to 50% for structural walls and 25% for insulation walls. Cob thermal properties are used in a comparative simulation case study of a typical house under French and UK climatic conditions. The energy performance of the conventional building is compared to a dual walled cob building, showing remarkable reduction in energy consumption as the cob walls, whilst maintaining comfortable indoor conditions without additional heating.

• In the past 15 years, household energy costs in Canada have risen at a much faster pace than real income, particularly in low-income households. Within-the-home energy poverty rates, as determined by various metrics, have followed suit. • Low-income households across Canada consume the least amount of energy per year and per unit heated area. They also tend to live in smaller dwellings which require more energy per unit floor area. • Low-income households tend to live in older, rented dwellings which are retrofitted less often than owner-occupied dwellings and are the least exposed to energy-saving technology. • Other developed countries, particularly in Europe, have studied energy poverty and affordability across their populations and have used their results to analyse cases of freeloading and split-incentive and to optimize government subsidy programs. • Energy efficiency rating systems for dwellings have been designed in some countries to help manage subsidies and determine patterns contributing to energy inefficiency. • Energy rate increases across developed nations are part of a global trend which could be alleviated through sponsored retrofitting and income transfers. • Several solutions can assist in reversing the increasing rates of energy poverty in Canada, including reinstating non-profit housing programs, providing on-site renewable energy generation and defining energy as a basic need. Energy in households is explored in the context of households in the Canadian built environment, in which considerable amounts of energy must be consumed as heating energy over the winter months, particularly in older or low-income dwellings. Recent Canadian poverty trends are explored and are analyzed in conjunction to the country's rising energy rates and effects on affordability. Past and current measures aimed at improving the existing housing stock in Canada and in other countries are explored, including retrofitting, behavioural change and renewable energy generation. The issue of thermal comfort in social housing programs is discussed, with examples from both developed and developing countries. Potential remedies to energy poverty situations in Canada are presented by discussing similar programs from other countries, including classification techniques and data analysis measures. Results from other countries and potential benefits to Canada are demonstrated, and the Quebec model of socially mandated energy is highlighted as an example which can be adopted by other provinces. [ABSTRACT FROM AUTHOR]

The study outlined in this article was intended to quantify the lifecycle assessment effects resulting from the different thermal storage capacities of the market‐relevant construction methods masonry, reinforced concrete and timber frame. Independently reviewed and verified life cycle assessments of representative model homes were the starting point of this study. But the findings of available computer simulations concerning the thermal behaviour of the model homes suggest that different thermal storage capacities of construction materials induce significant deviations of the heating demand, which should also precipitate significant lifecycle assessment differences – because the overall lifecycle assessment results of a building are generally substantially determined by the energy demand during its use phase. [ABSTRACT FROM AUTHOR]

Residential sector represents the largest energy consumer in the city of Pristina, as a capital of Republic of Kosovo. This is also the most diverse sector in terms of the energy sources used for space heating. Detailed analysis of different heating energy sources is pivotal for understanding the current situation as well as for any future systematic action in this field. In general, the main energy sources used for heating are known but the determination of their share still remains a challenge. Main focus of the current research is to identify the key heating energy sources, to analyze their share in different zones of Pristina, and to present the heated versus living area per different energy sources within dwellings. Data gathered in the field and presented in this paper are considered to be a first step in comprehensive analysis of the residential sector energy consumption in Pristina. [ABSTRACT FROM AUTHOR]

Reducing heating cost is a major challenge for greenhouses growers especially those located in cold regions. Several techniques have been applied to reduce greenhouse heating costs in winter season. This study presents a comprehensive review of different energy saving techniques that can be applied to reduce heating costs including energy-efficient greenhouse designs, use of energy-efficient covers, use of thermal curtains, energy-efficient management of indoor microclimates, selection of energy-efficient heating system, and the potential of using alternative energy sources. The energy saving potential of different design parameters (shape, orientation) depends greatly on the location, and the energy-saving potential of most passive heating systems (water tanks, rock bed) may not be feasible for commercial greenhouses production in cold regions. Alternative energy sources such as industrial waste heat, geothermal energy, and wood biomass could be a suitable option to reduce the greenhouse heating cost for large-scale production. However, it is important to consider the trade-offs between the agronomic need of plants and energy-saving potential of various energy-saving techniques, also the economic feasibility of energy saving systems in greenhouses. It can be concluded that this study could be useful for greenhouse growers, researchers, and manufacturer for creating sustainable energy-efficient greenhouse production in cold regions. Highlights • Energy saving potential of construction materials and dimensions of design explored. • Heating efficiency of different environmental control practises explored. • Heating systems, and use of alternative energy explored. • Energy saving could be significantly different based on the greenhouse location. [ABSTRACT FROM AUTHOR]

An assessment of the potential economic, environmental, and health benefits of substituting firewood with charcoal briquettes as heating fuel in cities located in the Forestry Belt in Chile is conducted. Experimental results obtained by the authors allowed to determine production yields and energy packing of charcoal briquettes obtained from Eucalyptus globulus and radiata pine residues. Given the large annual harvested surface of these two species, large quantities of residual biomass are left available at very low cost. The technology proposed to produce these charcoal briquettes is based in the process of pyrolysis in retort kilns. These give better results than traditional methods used until now in Chile to produce charcoal, but a higher technology level is required. Retort kilns rendered yield ratios of 0.247 and 0.286 [kg of charcoal/kg feedstock] for eucalyptus and radiata pine respectively. Charcoal briquettes gave a LHV (lower heating value) of 7836 kcal/kg and 7975 kcal/kg for eucalyptus and pine forest residues feedstock respectively, about twice that of dry firewood. Our economics analysis renders a cost of 0.1059 USD/kWh, which is competitive against firewood and other fuel options. In terms of health and environmental impact it is estimated that using charcoal briquettes from eucalyptus and pine harvested residues would reduce PM2.5 (particle matter <2.5 μg) air pollution, the most critical source of contamination in this geographic region, around 7.96 %, saving annually an estimated 9376 tons from being delivered into the atmosphere. An estimated 8.3 % of the annual firewood consumption (966,656 m3/year of which 2/3 is native) would be saved, so that 2041 ha of native deforestation would be avoided. • Recycling of radiata pine end eucalyptus forest residues • Replacement of firewood with charcoal briquettes as a heating fuel • Air pollution reduction in urban sites in the Forestry Belt in Chile [ABSTRACT FROM AUTHOR]

In South Korea, radiant floor heating has been used from old housing to the recently constructed residential buildings, which is called “Ondol”. The Ondol system is generally a water-based system and it uses hot water as a heat medium provided by boilers fueled by natural gas. With great effort to reduce greenhouse gas emissions, electric Ondol panels have been increasingly applied to the recent residential buildings for floor heating. While the prefab electric Ondol panels were developed with the demand for dry construction method, the information about the prefab electric Ondol system is not sufficient. For the present study, the thermal performance of the prefab electric Ondol panels was investigated through field measurement. In addition, the heating energy and economic performance of the electric panel were compared with the conventional Ondol system. As a result, a significant surface temperature difference was observed. Moreover, the heating cost for the prefab electric Ondol system was more expensive than the conventional system, even though a heat loss was observed by the operation of the conventional system.

Due to the cold winters in northeast China, the energy consumption of the rural residential buildings is much higher in this region than in other regions. In this study, the energy sustainability of bio-based wall construction is examined through applications in rural residential buildings. Comparisons of the energy sustainability of the bio-based wall constructions and the conventional wall constructions are evaluated using IESVE-2019 computational simulation. The results show notable reductions in heating energy requirements and coal use, which is the major heating source for rural residential buildings in China. The results show that reductions of 45.82–204.07 kWh/m2/year in heating energy requirements and more than 40% in coal use are possible through application of bio-based wall constructions. The application of bio-based wall construction will result in lower seasonal air pollution and coal use through straw burning in northeast China.

Highlights • One-parameter-at-a-time (OAT) approach was used for the sensitivity analysis. • Default values of the CSHHEAT model are reasonably acceptable. • Heating demand is highly sensitive to the thermal properties of cover, thermal blanket, and greenhouse perimeter. • Small change of indoor temperature and RH have significant effects on the heating demand for the coldest months. Abstract The sensitivity of a heating simulation model (CSGHEAT) was performed for estimation of the time-dependent heating requirement in a Chinese-style solar greenhouse in cold region. Results showed that the constant value of air thermal conductance is the main default parameter of the model that significantly affected the model output. The results also indicated the heating requirement is highly sensitive to the greenhouse design parameters including the thermal properties of cover, thermal blanket, and greenhouse perimeter. The thermal blanket is the most important design parameter for the Chinese-style solar greenhouse, and the heating requirement could be increased between 32 and 41% during the coldest three months (January, February, and December) for changing the thermal conductivity from 0.01 to 0.05 W/m K. Increasing daytime indoor set-point temperature from 19 to 23 °C would increase the heating demand between 13 and 20%, whereas the heating demand could be increased by 9–18% for increasing the night-time temperature from 16 to 20 °C. Results also indicate the heating demand could be reduced up to 20% during the coldest period for increasing the indoor relative humidity from 70 to 90%. The results from this study could be useful for understanding the energy saving management of greenhouse operations and for designing the energy-efficient Chinese-style solar greenhouses in cold regions. [ABSTRACT FROM AUTHOR]

The domestic sector uses the majority of the energy consumed in Palestine. The Palestinian Central Bureau of statistics (PCBS) performs periodic statistics regarding the average energy consumption of the households, but there is no up to date breakdown of the energy consumption in the residential sector. The Palestinian energy sector main challenges are the high fuel prices, lack of sustainable consumption and energy insecurity. Developing energy policies and studying the potential of shifting towards more independent and sustainable energy sources need a clear understanding of the current energy consumption. A survey was used to collect relevant quantitative and qualitative data. The total number of households in Hebron who responded to the survey was 322 households. The survey covered physical characteristics of the dwellings, socioeconomic features of the households in addition to the pattern of heating the spaces, quantity and type of fuel used for heating. On average the households heated only 9.2% of the total area of their houses during the winter days. The survey revealed that households spend 3.5%–21.6% of their monthly income on space heating during winter. The main contribution to knowledge of this paper is a regression model to estimate energy consumption based on the data collected from the survey. The regression model is developed with an R 2 adjusted 0.606 indicating 60.6% accuracy of the predicted energy consumed for heating. The regression model depends on 14 parameters which include the type of settlement, physical characteristics of the dwelling that are housing typology, level of thermal insulation of the walls, the main building materials and the housing age. It also depends on socioeconomic parameters which are the family monthly income and the occupancy period. Moreover, the type of the heating system used, the number of heated months and the nominal heated area were influential parameters in this model. The significance of this paper stems from the methodology that propose an alternative to the energy audit and simulation methods. The proposed method can be used in contexts where a combination of energy resources is used with no proper metering system and with the absence of accurate data that is needed for simulation. [ABSTRACT FROM AUTHOR]

Abstract: Statistic energy ratings for Germany: Heat energy consumption trends of the dwelling stock since 2004 Representative energy ratings for the German dwelling stock between 2004 and 2016 are reported. The statistical base comprises 1,6 million building billings, 1,2 billion m2 living area, 180 TWh energy and 200 million m3 drinking water, all differentiated by building size and heating system type. We observe an average reduction of room‐heating by 11–12 %. Contrary and at the same time an increase of water‐heating‐energy (TWE) of about 5–6 % takes place, as well as an effective increase of the TWE‐fraction by 2 %, from 22 to 24 %. The effective heat energy reduction is apparently levelling out: Already 2/3rd of reduction was achieved during the time interval before 2010, only 1/3rd during the following years. Calculating similar energy ratings for the 19 million German flats in single or double houses leads to about 1/3rd less relative energy‐reduction, thus the heat‐energy‐consumption within years 2013–2016 was only 8–8,5 % lower compared to years 2004–2008. The misgivings not fulfilling the expectations as postulated by the EnEV have again proved true; indeed, the statistics document a continuous discrepancy to the EU 20‐20‐20 climate goals. With respect to effective CO2‐reduction, EnEV‐ claims concerning living flats have become much less convincing. Instead, the focus should resolutely turn to reduction of the primary energy factor, namely on the systematic change to regenerative energy, more efficient coupling of energy sectors in order to achieve effective traffic reduction as well as investments into digital infrastructure within flats raising their energy efficiency and supporting Ambient Assisted Living. [ABSTRACT FROM AUTHOR]

Low-carbon transition in the non-electric energy sector, which includes transport and heating energy, is necessary for achieving the 2 °C target. Meanwhile, as non-electric energy accounts for over 60% of total water consumption in the energy supply sector, it is vital to understand future water trends in the context of decarbonization. However, few studies have focused on life-cycle water impacts for non-electric energy; besides, applying conventional LCA methodology to assess non-electric energy has limitations. In this paper, a Multi-Regional Hybrid Life-Cycle Assessment (MRHLCA) model is built to assess total CO 2 emissions and water consumption of 6 non-electric energy technologies – transport energy from biofuel and gasoline, heat supply from natural gas, biogas, coal, and residual biomass, within 7 major emitting economies. We find that a shift to natural gas and residual biomass heating can help economies reduce 14–65% CO 2 and save more than 21% water. However, developed and developing economies should take differentiated technical strategies. Then we apply scenarios from IMAGE model to demonstrate that if economies take cost-effective 2 °C pathways, the water conservation synergy for the whole energy supply sector, including electricity, can also be achieved. [ABSTRACT FROM AUTHOR]

Owing to the eye‐catching pros of high energy and environmental performances, numerous ground‐source heat pump (GSHP) systems have been employed in domestic and industrial buildings throughout the world. One of the proved renewable energy technologies is the GSHPs which is able to fulfill the gap between cooling and heating. The main contribution of this article is to present a fully description and critical review of the GSHP systems along with their current developments. At first, the energy efficiency and working standard of a heat pump are introduced. Furthermore, an expansive description of the GSHPs and its advances, and a fully explanation of the ground‐couplet (GCHP) heat pumps, ground‐water (GWHP), and surface water (SWHP) are provided. The mainly representative ground thermal response examination approaches and simulation for the vertical ground heat exchangers presently existing are reviewed counting the heat transfer progressions inside and outside the holes. Similarly, various info regarding a different GWHP by a heat exchanger with different structures, and the opportunity to gain the enhanced energy efficiency with joint cooling and heating using GCHP are explained. The numerous hybrid GCHP systems for heating or cooling‐dominated constructions are appropriately illustrated. It can be deduced that the GSHP technology can be employed both in hot and cold weather areas and the potential of energy saving is noteworthy. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 1241–1265, 2018 [ABSTRACT FROM AUTHOR]

Educational buildings are buildings with special social importance, and their energy consumption requires particular attention. Since the majority of educational buildings in Serbia were built between 1950 and 1990, with concrete frame, brick walls and poor thermal insulation, it can be concluded that these buildings have relatively high potential for thermal energy savings. In this paper, specific heat consumption of educational buildings (42 different institutions classified throughout educational levels) in the city of Kragujevac (Serbia) was analysed in order to determine their specific heat consumption (per heated floor area and per user) and to list the priorities for refurbishment. According to educational level, they were classified in preschool buildings, elementary and high schools and faculties (university buildings). Data about heat energy consumption were collected during several heating seasons in order to minimise the influence of seasonal climate variations. Values of specific heat energy consumption of the buildings were benchmarked with data on specific heat consumption of schools from different European countries. In order to accomplish the tasks, authors introduced the concept of weather normalised specific heat consumption. Results of the performed analysis pointed out preschool and elementary school buildings as refurbishment priorities since their average specific heat consumption is the biggest (186 and 176 kWh/m2/a, respectively). Besides, normalised specific heat consumptions of the educational buildings in Kragujevac are higher than in comparing countries, and the potential for their energy efficiency improvement is significant. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effect of demand response (DR) actions on energy consumption and energy cost with two alternative heat generation systems in a detached house in a cold climate. The heat generation systems are a ground source heat pump coupled with a two-storage tank system (GSHP heating system) and a water-based electric heating system coupled with a similar storage tank system (storing electric heating system). Four rule-based DR control algorithms were applied and studied for two alternative heat generation systems. Two rule-based DR control algorithms from previous study were applied and investigated for these heat generation systems based on real-time hourly electricity price and future hourly electricity prices based on the blocking-maximum subarray method. Two new rule-based DR control algorithms based on future hourly electricity prices were developed and investigated for these heat generation systems based on the sliding-maximum subarray method and moving average method. This research was implemented with the validated dynamic building simulation tool IDA ICE. The obtained results show that the maximum annual savings in the heating energy and cost take place using the rule-based DR control algorithm based on the sliding-maximum subarray method. As well, these savings are about 10% and 15%, respectively, for the GSHP heating system; and about 1% and 8%, respectively, for the storing electric heating system. [ABSTRACT FROM AUTHOR]

Changes in weather conditions due to global warming affect the energy demand of buildings, resulting in changes in the installed heat capacity of district heating systems. The study provides a methodology for assessing the potential effects of climate change in combination with renovation of existing building stock on building heat demand. The system dynamics approach was used for investigation of the interlinkages and causality of energy efficiency, global warming, and total installed heat source capacity. Variations in the heating load of a district heating system due to improvements in building energy efficiency were studied in combination with three climate change scenarios. The optimal balance point between investment at the heat source side and at the heat consumers side was also investigated. The interaction of global warming, building heat demand and installed capacity of the district heating system was identified by the levelized investment approach. The study shows that global warming directly influences the heating degree-days and reduces the heat demand in the case study considered (part of the Riga city). A significantly higher impact on heat demand could be achieved by implementation of building renovation, however the funding available for this purpose is insufficient in the studied case. • The impact of global warming reduces heat demand by 13, 17, and 24% in low, medium, and high scenarios. • Provided methodology couples the system dynamic approach with the building heat balance model. • Investment in heat saving by the renovation of buildings and heat production technology are interlinked. [ABSTRACT FROM AUTHOR]