Increased Heat Storage Research Articles

The Regulation of Temperature Fluctuations and Energy Consumption in Buildings Using Phase Change Material–Gypsum Boards in Summer

This study examined the thermal performance of Comfortboard23, a commercial gypsum board from Knauf infused with phase change material (PCM). Structural characterization using XRD and SEM confirmed the presence of microencapsulated PCM within the gypsum matrix. The study does not provide a direct comparison between Comfortboard23 and other PCM-integrated gypsum boards on the market. This is a limitation of the research. A comprehensive comparison would involve testing multiple products under identical conditions, and evaluating factors such as thermal performance, cost-effectiveness, durability, and ease of installation. Thermal characterization involved a novel low-scale thermal chamber to measure U-value, thermal conductivity, heat storage capacity, and dynamic thermal response. Results showed incorporating PCM decreased the U-value by 2% compared to standard gypsum boards. Additionally, PCM inclusion increased heat storage capacity by around 45% and improved dynamic thermal characteristics by decreasing thermal stability coefficient from 0.92 to 0.76 and increasing thermal lag from 0.27 to 0.49 h. The 45% increase in heat storage capacity of Comfortboard23 could lead to a 10–20% reduction in heating and cooling energy consumption, improved thermal comfort, and potential HVAC downsizing. Exact benefits depend on climate, building design, and occupancy patterns, necessitating further research in diverse real-world settings. The findings demonstrate Comfortboard23’s potential for enhancing thermal energy storage in buildings, contributing to energy savings, improved thermal comfort, and reduced temperature fluctuations across varying daily temperatures. Overall, the study highlights the promise of Comfortboard23 as an energy-efficient PCM-integrated building material.

New design concept and thermal performance of a composite wall applied in solar greenhouse

Traditional solar greenhouse wall combines the functions of heat preservation and heating. It cannot accommodate both heat storage and insulation that the heat stored in the wall is uncontrollably lost as the temperature difference between the interior and exterior increases. This study proposed a novel composite wall (NCW) with an independent modular wall made of expanded polystyrene board and reinforced concrete (EPCW), and a solar water heating system (SWHS). The thermal properties of traditional brick walls and novel composite walls were assessed through field tests. Numerical simulations were utilized to analyze the heat transfer processes occurring within the wall, enabling determination of the magnitude of heat transfer towards both the interior and exterior. The thermal resistance of the ECPW with the same thickness is 1.5 times higher than that of clay bricks. Meanwhile, the heat loss from the exterior wall is reduced by 44 % through the EPCW. The SWHS installed on the greenhouse north wall increases heat storage by 89 % and heat release by 256 %. The greenhouse annual input cost for using NCW is 2.5 USD m−2 year−1 in 20-year life. It is 32.4 % lower than that of a conventional clay brick greenhouse, and has some promotional and application value.

The Morphological and Thermal Characteristics of Hollow-Glass-Microsphere-Coated Phase Change Material–Cow Pie Embedded Recycled Plastic Tiles for Cool Roofs

This study addresses the global plastic waste crisis and the urban heat island effect by developing an innovative solution: recycled plastic roof tiles embedded with phase change material (PCM) and coated with hollow-glass-microsphere-based white paint. The samples were fabricated with cow pie fibers, OM37 and OM42 PCM materials with different wt./vol. values, i.e., 15/50, 20/50, 25/50, 30/50 ratios. The fabricated tiles were coated with hollow glass microspheres to provide a reflective layer. The tiles’ effectiveness was evaluated through morphological examination and thermal analysis. The SEM analysis revealed an excellent bonding ability for the PCM blend, i.e., OM37 and OM42 at a 20/50 ratio (wt./vol.) with cow pie fibers. Adding cow pie fibers to the PCM shifted the melting points of OM37 and OM42, indicating an increased heat storage capacity in both blends. The thermal conductivity results revealed decreased thermal conductivity with an increased cow pie fiber percentage. The recycled plastic roof tile of the PCM composite at a 20/50 (wt./vol.) ratio showed good thermal properties. Upon testing in real-time conditions in a physical setup, the roof tiles showed a temperature reduction of 8 °C from outdoors to indoors during the peak of summer. In winter, cozy temperatures were maintained indoors due to the heat regulation from the roof.

Challenge to Lake Ecosystems: Changes in Thermal Structure Triggered by Climate Change

Human activities, global warming, frequent extreme weather events, and changes in atmospheric composition affect the solar radiation reaching the Earth’s surface, affect mass and heat transfer at the air–water interface, and induce oscillations in wind-driven internal waves. This leads to changes in the spatiotemporal characteristics of thermal stratification in lakes, altering lake circulation patterns and vertical mass transfer. However, thermal stratification structures are often overlooked. The intensification of lake thermal stratification due to warming may lead to increased release of bottom pollutants, spreading through the dynamic behavior of the thermocline to the epilimnion. Moreover, the increased heat storage is beneficial for the growth and development of certain phytoplankton, resulting in rapid transitions of the original steady state of lakes. Consequently, water quality deterioration, ecological degradation, and declining biodiversity may occur. Conventional surface water monitoring may not provide comprehensive, accurate, and timely assessments. Model simulations can better predict future thermal stratification behaviors, reducing financial burdens, providing more refined assessments, and thus preventing subsequent environmental issues.

Design and optimization of a hybrid cooling configuration combining PCM and liquid cooling for Li-ion battery using data-based response surface approximation model

Effective thermal management is crucial for safe operation of electric vehicles. This study proposes a novel hybrid cooling system that using phase change material (PCM) and liquid cooling to address issues such as leakage, non-uniform temperatures under high discharge rates. A comprehensive 3D model was developed to analyze the influence of geometric parameters on the cooling system. Response surface approximation modeling was used to optimize the layout parameters of the PCM. The results show that the hybrid cooling outperforms other methods, maintaining the cell temperature with 35 ℃ and the temperature difference within 4 ℃. The thickness of the PCM is a significant factor, as it increases heat storage capacity and reduces temperature; however, exceeding a certain threshold leads to increased thermal resistance. A non-uniform PCM layout can reduce the temperature difference by 26 %. An optimal PCM thickness of 2.5 mm to 3 mm ensures that the maximum temperature remains below 32.5 ℃, with a temperature difference within 2 ℃. The lowest temperature difference is achieved with a vertical layout height of 70 mm and a horizontal layout thickness of 3 mm. These findings are valuable for enhancing the thermal management of lithium-ion battery.

Modeling and optimization of a passive building HVAC system based on improved PSO and H-J Algorithm

Passive buildings employ the principles of active optimization and passive priority to demonstrate their energy-saving, comfortable, and cost-effective qualities, thereby addressing energy consumption in an efficient manner. However, it cannot be ignored that the Heating Ventilation Air Conditioning (HVAC) system is still the largest energy consumer, especially when it is necessary to maintain the comfort of the indoor environment. Consequently, the control and optimization of the HVAC system is a research hotspot and a challenge in the field of building energy conservation, as it is the key to achieving ultra-low energy consumption operation in passive buildings while ensuring the thermal comfort of the indoor environment. This paper presents a comprehensive modeling, control, and optimization framework for the efficient operation of HVAC systems in a passive building located in Jinan, China. Firstly, the HVAC system is modeled using the transient system simulation tool (TRNSYS), GenOpt, Java, and other software. Secondly, the HVAC system’s year-round operation is simulated using specific configurations. In order to enhance the energy-saving effect, a strategy of increasing heat storage and return air ducts was proposed, and a significant energy-saving effect (approximately 17.31%) was realized. Lastly, the data communication interface with GenOpt is established utilizing the TRNOPT module, a method for actively optimizing the refrigerant temperature is proposed, and recalculation and optimization are carried out utilizing the swarm intelligence algorithm and the pattern search algorithm (Hooker-Jeeves algorithm, H-J algorithm). The final optimization results demonstrate a 19% reduction in energy consumption relative to the baseline heat recovery model, validating the applicability of the optimization method under this strategy. The control and optimization method of the HVAC system proposed in this paper can further exploit the energy-saving potential of the passive building HVAC system and will contribute to the advancement of building energy conservation.

The potential of arch-shaped fins for energy-charge enhancement in triplex-tube heat storage: Comparative analysis and optimization

Incorporating PCMs with thermal storage systems offer significant potential for improving the energy efficiency of diverse applications, including solar thermal power plants, air conditioning systems, and building heating and cooling systems. However, a key challenge in designing these systems is achieving efficient and rapid PCM melting during the charging process. This study aims to analyze and report on the potential of arch-shaped fins in enhancing the melting rate and overall performance of horizontal triplex-tube storage systems. The influences of fin base height and fin connecting angles were analyzed via simulations. The optimal arch-shaped fin design reduced melting time by 53 % and improved heat storage rate by 117 % compared to the no-fin case. Specifically, equal inner/outer fin base heights of 10 mm minimized melting time to 14.8 min and maximized heat storage to 477.2 W. Increasing the inner fin connecting angle from 0° to 120° decreased melting time by 15.2 % to 12.1 min and increased heat storage by 18.0 % to 591.3 W. Reducing the outer fin connecting angle from 240° to 0° reduced melting time by 10.8 % to 11.5 min and improved heat storage by 12.3 % to 591.3 W. These findings would have implications for advancing the design and optimization of heat storage systems, leading to improved performance and increased utilization of sustainable energy sources.

Self-reported effects of warm seasonal temperatures in persons with spinal cord injury

Objective Spinal cord injury (SCI) interrupts motor, sensory, and autonomic pathways, impairing mobility and increasing heat storage during warm seasonal temperatures due to compromised autonomic control of vasodilation and sweating and recognition of body temperature. Thus, persons with SCI are more vulnerable to hyperthermia and its adverse effects. However, information regarding how persons with SCI perceive warmer seasons and whether thermal discomfort during warmer seasons restricts routine activities remains anecdotal. Design Cross-sectional, self-report surveys. Setting VA Medical Center and Kessler Institute for Rehabilitation. Participants Three groups of 50 participants each: tetraplegia, paraplegia, and matched non-SCI controls. Outcome Measures Tetraplegia, paraplegia, and control groups responded “yes” or “no” when asked whether warm seasonal temperatures adversely affected comfort or participation in routine activities. Results The percentage of responses differed among tetraplegia, paraplegia, and control groups when asked if they required ≥20 min to cool down once overheated (44 vs. 20 vs. 12%; X 2 = 14.7, P < 0.001), whether heat-related discomfort limited their ability to go outside (62 vs. 34 vs. 32%; X 2 = 11.5, P = 0.003), if they needed to use a water-mister because of the heat (70 vs. 44 vs. 42%; X 2 = 9.8, P = 0.008), and if heat-related discomfort limited participation in social activities (40 vs. 20 vs. 16%; X 2 = 8.7, P = 0.01). Conclusion Warmer seasonal temperatures had a greater negative impact on reported comfort and daily activities of persons with SCI than non-SCI controls. Those with tetraplegia were most adversely affected. Our findings warrant increasing awareness and identifying interventions to address the vulnerability of persons with SCI to hyperthermia.

Review on influence of nanomaterials on thermal energy storage methods

Thermochemical heat and latent heat storage are two promising methods for thermal energy storage (TES) that have the potential to increase energy efficiency and sustainability. Due to its vast advantages, TES systems have found application in numerous waste heat sources such as solar plants, automobiles, and industries. Despite their benefits, both storage technologies have their limitations. The use of nanomaterials in latent and thermochemical heat storage has improved results in terms of improving heat storage performance and overcoming limitations. This paper discusses the role of various potential nanomaterials such as expanded Graphite, Aluminium Oxide, Titanium Oxide, Silicone, Graphene, Carbon Nanotubes, and Nanofibers in efficient thermal energy storage. The aim of the present study to explores the effects of various nanomaterials on storage methods and their utilization. The addition of TiO2-based nanoparticles in the CaO thermochemical material increased heat storage density and the cyclic stability of the heat storage system. The latent heat capacity of Wax PCM increased by adding 1 % of TiO2 into the paraffin. The addition of nanomaterials significantly improved the energy storage parameters such as thermal conductivity, thermal stability, thermal reliability, specific heat capacity, heat storage density and cyclic stability of the thermal energy storage materials.

Effect of Ice Slurry Ingestion on Post-Exercise Physiological Responses in Rugby Union Players

Delayed recovery of the core body temperature after exercise adversely affects physiological functions, and the effects of ingesting lower-temperature ice slurry on post-exercise recovery remain unclear. We investigated the effects of ingesting −2 °C ice slurry on physiological recovery after field-based rugby union training. Fifteen university rugby union players participated in our randomized controlled study. The players participated in the training for 60 min in a hot outdoor environment (wet-bulb globe temperature, 30.5 °C). Physiological responses were measured during a physical performance test performed after the players ingested either −2 °C-ice slurry (ICE, N = 7) at 5 g/kg body mass or a 30 °C-fluid (CON, N = 8) during the 15 min recovery period after the training. Tympanic temperatures and heart rates were measured as the physiological indices, as well as heat storage. The ICE group showed significantly decreased tympanic temperatures and heart rates (p &lt; 0.05) during the recovery period and increased heat storage (p &lt; 0.05) but did not show improvement of physiological indices during the performance test compared to the CON group. These results suggest that ingestion of −2 °C ice slurry in even lower amounts than those previously reported is useful for physiological recovery after training in hot outdoor environments.

Thermomechanical Performance Analysis of Novel Cement-Based Building Envelopes with Enhanced Passive Insulation Properties.

The design of new insulating envelopes is a direct route towards energy efficient buildings. The combinations of novel materials, such as phase-change (PCM), and advanced manufacturing techniques, such as additive manufacturing, may harness important changes in the designing of building envelopes. In this work we propose a novel methodology for the design of cement-based building envelopes. Namely, we combined the use of a multiscale, multiphysical simulation framework with advanced synthesis techniques, such as the use of phase-change materials and additive manufacturing for the design of concrete envelopes with enhanced insulation properties. At the material scale, microencapsulated PCMs are added to a cementitious matrix to increase heat storage. Next, at the component level, we create novel designs for the blocks, here defined as HEXCEM, by means of additive manufacturing. The material and component design process is strongly supported on heat transfer simulations with the use of the finite element method. Effective thermal properties of the mixes can be obtained and subsequently used in macroscale simulations to account for the effect of the volume fraction of PCMs. From the experimental and numerical tests, we report an increase in the the thermal inertia, which results in thermal comfort indoors.

Assessing the Impacts of Land Use Diversity on Urban Heat Island in New Cities in Egypt, Tiba City as a Case Study

Egypt had two problems: population growth and population concentration, which were solved by moving to new cities. Rapid urbanization and changing lifestyles have disrupted the ecological structure of cities. This has given rise to the phenomenon of urban heat islands (UHI). This phenomenon is characterized by higher air and surface temperatures in cities than in rural areas. The research into this phenomenon is based on land surface temperatures (LST), which are closely related to land use characteristics (LU). Researchers can now measure LST across wide areas with great temporal and spatial accuracy using remote sensing (RS), Geographical information systems (GIS), and statistical approaches. Google Earth's high-resolution maps also help identify LU classes. All of these assisted in achieving the study's main goal of examining the impact of LU on LST and hence the phenomena of UHI in new cities. The LU diversity was determined using high-resolution Google Earth maps, while the LST was extracted using free RS data. The study concluded that paved and unpaved roads, as well as unoccupied places, absorb considerable amounts of solar radiation, leading to increased heat storage and UHI. The coldest temperatures were reported in residential and green regions.

An experimental investigation of the effectiveness of partially and fully submerged metal hollow-fins and jute cloth wick-fins on the performance of a dual-basin single-slope solar still

The rapid growth of the population and industrialization have caused a global crisis for potable water, which has triggered researchers to propose an alternative solution to the problem. Solar still is a solar energy-based device confronting the problem of low productivity. The prime objective of the present study is to investigate the effectiveness of hollow-fins and wick-fins on the performance of dual-basin single-slope solar still. The performance of solar still with hollow-fins, wick-fins, and without fins has been compared in two sets of experiments for partially and fully submerged cases. The distillate outputs from stills for partially submerged fins were 4.2313 L/m2 (8.96% higher) with wick-fins, 4.0733 L/m2 (4.89% higher) without fins, and 3.8833 L/m2 with hollow-fins. The wick-fins improve the performance of the solar still by increasing the evaporation surface and rate of evaporation through capillary action. The distillate outputs from stills for fully submerged fins were 3.6554 L/m2 (3.91% higher) with wick-fins, 3.8534 L/m2 (9.54% higher) without fins, and 3.5179 L/m2 with hollow-fins. The reason for the higher performance of still without fins are the highest temperature of the lower basin; reduced heat loss due to increased heat storage capacity of brackish water; a lower temperature difference between the lower basin and saline water that increases evaporation of brackish water in the lower basin; the highest temperature difference between saline water and the upper basin glass cover that enhances the condensation rate of water vapour in the upper basin. The still with wick-fins proved to be the most efficient from the performance and economic point of view for partially submerged fins, while the still without fins proved to be the most efficient for fully submerged fins.

Impact of Thermohaline Variability on Sea Level Changes in the Southern Ocean

AbstractThe Southern Ocean is responsible for the majority of the global oceanic heat uptake that contributes to global sea level rise. At the same time, ocean temperatures do not change at the same rate in all regions and sea level variability is also affected by changes in salinity. This study investigates 10 years of steric height variability (2008–2017) in the Southern Ocean (30°S to 70°S) by analyzing temperature and salinity variations obtained from the GLORYS‐031 model provided by the European Copernicus Marine Environment Monitoring Service. The thermohaline variability is decomposed into thermohaline modes using a functional Principal Component Analysis. Thermohaline modes provide a natural basis to decompose the joint temperature‐salinity vertical profiles into a sum of vertical modes weighted by their respective principal components that can be related to steric height. Interannual steric height trends are found to differ significantly between subtropical and subpolar regions, simultaneously with a shift from a thermohaline stratification dominated by the first “thermal” mode in the north to the second ’saline’ mode in the South. The Polar Front appears as a natural boundary between the two regions, where steric height variations are minimized. Despite higher melt rates and atmospheric temperatures, steric height in Antarctic waters (0–2,000 m) has dropped since 2008 due to higher salt content in the surface and upper intermediate layer and partially colder waters, while subtropical waters farther north have mostly risen due to increased heat storage.

An experimental and numerical analysis of an improved thermal storage tank with encapsulated PCM for use in retrofitted buildings for heating

In the building sector, 40% of final energy is used for heating and cooling. Up to 75% of this is used in residential buildings. It is necessary to take a step forward and reduce this share of energy consumption, in particular through the use of efficient technologies and their integration into the system of renovation of residential buildings, which is a major challenge for future research in this field. An important technology for achieving this goal is heat storage, where the use of phase change materials as heat storage material allows for a higher energy density. The main advantage of using heat storage technologies is the solution of the problem of the temporal divergence of energy demand and the possibility to use a higher share of energy from renewable sources, e.g. such as solar energy. Solar energy as a resource can be used during the day, when production is higher than demand, which allows storing energy for a later period of demand. This also improves the efficiency of the heat generators in the system in which the thermal storage is integrated. The focus of the present study is on the investigation of phase change materials (PCM) as thermal storage in the conventional water tank storage. A comparison was made between a conventional sensible thermal energy storage tank and a hybrid latent heat storage tank, where the PCM was encapsulated in cylindrical nodules and integrated into the water tank to improve the energy density of the conventional water heat storage tank. The results of the experiment showed that 15% of the PCM inside the water storage tank increases heat storage for 70% over conventional heat storage tank with water only inside. The measured experimental data were compared with the simulation results from TRNSYS model to enable further analysis and improvement of the heat storage tank with PCM integration.

ENVIRONMENTAL PARAMETERS FOR CAMPUS OUTDOOR SPACE: A MICROCLIMATE ANALYSIS OF THE EASTERN MEDITERRANEAN UNIVERSITY (EMU) CAMPUS

ABSTRACT Open spaces—whether public, urban, or part of a campus—offer a variety of activities and opportunities to people. Therefore, open spaces should be considered a vital component of any built-up area and designed to meet the needs and address the comfort of potential users. Because of their presence in daily life and their preponderance of characteristics, open spaces have drawn the attention of many researchers, designers, and planners with varying perspectives. The current study takes a scientific approach to analyzing the environmental parameters of the Campus Outdoor Space (COS) in the case of the Eastern Mediterranean University (EMU). An extensive literature review supported the identification of seven important environmental parameters effective in the microscale analysis of a COS: geographical location, meteorological situation, urban form, surface materials, amount of vegetation and watershed, and anthropogenic pollution. Analysis of the environmental parameters called for a hybrid method that included a detailed field survey and the following set of simulations: sun-path, radiation, sky view factor, and turbulence analysis. The accuracy of the field survey directly contributed to the effectiveness of the simulations. Grasshopper® 3D software and Computational Fluid Dynamics were used to simulate the conditions of the EMU study area. The outcomes show that the spatial organization, building forms, and building orientation negatively affect the COS of EMU. In the Mediterranean climatic region of EMU, shade and flowing breezes greatly enhance comfort and usability of outdoor spaces from April to October. The massive form of buildings and minimal planning for effective building orientation to the sun increased heat storage capacity and neglected prevailing winds, resulting in flow separation and formation of eddies on the leeward side of buildings. These negatively influenced the microclimate, and thereby user comfort, at the core of the EMU’s main COS.

Numerical Simulation Study on Structure Optimization and Performance Improvement of Hot Water Storage Tank in CHP System

The central heating technology with thermal storage technology is an important means to realize thermoelectric decoupling, meet heating demand, reduce primary energy consumption, and protect the ecological environment. For this paper, the numerical simulation method was used to study the temperature variation of large-capacity hot water storage tank (HWST) in an actual combined heat and power system. The influence of various factors, including the length diameter ratio, water supply temperature, and water supply flow, as well as the orifice diameter and number of the water distributor, on the flow uniformity and performance of the HWST was investigated. The results show that the heat storage efficiency and flow uniformity of the HWST can be improved by properly increasing the water supply flow, the orifice diameter, and number of the water distributor. Increasing the length diameter ratio can improve the flow uniformity, but it will reduce the heat storage efficiency of the HWST. Increasing the water supply temperature can increase heat storage efficiency of the HWST and accelerate the stratification of cold and hot water in the tank. Besides, the comprehensive analysis of the non-dimensional exergy loss calculation results, velocity field, and temperature field show that there is a certain coupling relationship between the non-dimensional exergy loss and flow uniformity at the initial stage of heat storage. In practical application, the influence of these factors on flow uniformity, heat storage efficiency, and non-dimensional exergy loss should be comprehensively considered in order to achieve the best heat storage and release performance of the HWST. This paper provides some engineering guidance for the application of large-capacity heat storage tanks in the combined heat and power (CHP) system.

Thermo-ecological cost assessment and optimization for a hybrid combined cooling, heating and power system coupled with compound parabolic concentrated-photovoltaic thermal solar collectors

The aim of this work is to optimize and minimize the thermo-ecological cost (TEC) of a novel hybrid combined cooling heating and power (CCHP) system integrated with solar energy. A basic natural gas CCHP system based on internal combustion engine (ICE) is coupled with compound parabolic concentrated-photovoltaic thermal (CPC-PVT) collectors to construct a novel hybrid CCHP system. To minimize the TEC, an optimization methodology was proposed to optimize the configurations and installations of ICE and CPC-PVT, as well as the operation strategies. The TECs of multi-products of the CCHP system were assessed and compared in the following electrical load (FEL) and following thermal load (FTL) modes. The impacts of key parameters on TEC were analyzed and discussed. The results of a case study indicated that the system integrated with 100% photovoltaic covered ratio and 400 kW ICE gets the lowest TEC of 2.36 J/J in the FTL mode. The TECs of electricity decline 28.8% and 17.0% in the FEL and FTL modes, respectively when the photovoltaic covered ratio increases from 0 to 1.0. The increasing heat storage ratio leads to the increase of TEC of heat exergy carried by water due to the heat loss.

Deep Atlantic Ocean Warming Facilitated by the Deep Western Boundary Current and Equatorial Kelvin Waves

Increased heat storage in deep oceans has been proposed to account for the slowdown of global surface warming since the end of the twentieth century. How the imbalanced heat at the surface has been redistributed to deep oceans remains to be elucidated. Here, the evolution of deep Atlantic Ocean heat storage since 1950 on multidecadal or longer time scales is revealed. The anomalous heat in the deep Labrador Sea was transported southward by the shallower core of the deep western boundary current (DWBC). Upon reaching the equator around 1980, this heat transport route bifurcated into two, with one continuing southward along the DWBC and the other extending eastward along a narrow strip (about 4° width) centered at the equator. In the 1990s and 2000s, meridional diffusion helped to spread warming in the tropics, making the eastward equatorial warming extension have a narrow head and wider tail. The deep Atlantic Ocean warming since 1950 had overlapping variability of approximately 60 years. The results suggest that the current basinwide Atlantic Ocean warming at depths of 1000–2000 m can be traced back to the subsurface warming in the Labrador Sea in the 1950s. An inference from these results is that the increased heat storage in the twenty-first century in the deep Atlantic Ocean is unlikely to partly account for the atmospheric radiative imbalance during the last two decades and to serve as an explanation for the current warming hiatus.

Autoclaved aerated concrete: Influence of heat storage capacity on thermal performance and thermal comfort

AbstractBackgroundThe heat storage capacity of building materials can have a significant influence on energy consumption and thermal comfort of buildings.AimThis paper investigates the correlations between heat storage capacity and thermal performance.Materials and MethodsA test building made of autoclaved aerated concrete (AAC) bricks was constructed in Kloster Lehnin/Emstal (Germany) with the same heat transition coefficient U for the walls, floor, and roof. The heating and ventilation of the building is controlled automatically. Xella and the Department of Building Physics/Low Energy Buildings of Technische Universität Kaiserslautern have been monitoring the test building since April 2017. The thermal performance and comfort of the AAC test building were investigated by measurements and simulations. The results were compared to simulations of a light weight building with the same geometry and heat transition coefficients U.ResultsThe examinations showed that the heat storage capacity of the AAC has a positive influence on summer heat protection and thermal comfort of buildings in comparison to light weight constructions (LWC).ConclusionIn summer, the increased heat storage capacity of AAC compared to LWC improves thermal comfort. During the heating period, AAC buildings with a higher heat storage capacity in comparison to LWC offer the advantage of a slower cooling down of the indoor air temperature.