Small Residential Buildings Research Articles

THE IMPACT OF DESIGN VARIABLES ON THE HEAT DEMAND OF A RESIDENTIAL BUILDING IN THE COLD REGION

This study is about the impact of early design decisions on the heat demand of a small residential building. Heat demand is a significant part of the energy use of residential buildings in the Cold regions. Reducing this demand will reduce the strain on national energy resources and even allow buildings to become energy neutral or independent with the addition of energy supply and storage systems. Based on a case study building of apartments, the simulation study explores the impact of several individual design aspects: insulation, orientation of glass facades and building shape. Furthermore, the balcony facade of the case study building is compared to a plain facade and a sunspace (balconies with a glass facade) in terms of heat demand and comfortable use (operative temperature). Based on these studies a final set of design guidelines is developed for designers interested in designing small residential buildings with low heat demand.

STATE-OF-THE-ART APPLICATION OF THE LOG-PILING METHOD IN THE ROLE OF SHALLOW GROUND IMPROVEMENT FOR LIQUEFACTION MITIGATION

<p>This research paper focuses on evaluating the log piling technique as a sustainable, cost-effective, and environmentally friendly solution for reducing soil liquefaction risks during earthquakes. Although this method has been used extensively in Japan, mainly aiming for complete soil layer penetration, its economic viability is questionable in cases requiring very deep soil improvements. The study highlights that shallow ground improvement can notably enhance the seismic behavior of the soil-improvement-structure system, as evidenced by the reduced total and penetration settlements caused by liquefaction. The paper presents a methodology for determining the optimal dimensions of the modified ground zone using both small and medium-scale 1-g shaking table tests. </p> <p>The small-scale tests involve a detailed parametric study, examining variables like improvement width, pile spacing, and the depth-to-thickness ratio of the improved layer. Medium-scale tests, on the other hand, are geared towards identifying the minimum effective pile length. This approach provides a practical guideline for engineers to implement log piling for small residential buildings. Additionally, the paper utilizes finite element method (FEM) effective stress analysis, incorporating a PLAXIS 2D-based constitutive model (PM4Sand) calibrated with laboratory undrained cyclic torsional tests. This model accounts for the changes in effective stress during seismic activities. Finally, the study correlates its numerical findings with the results from the 1-g shaking table experiments, offering a well-rounded perspective on the effectiveness of log piling in mitigating liquefaction risks during seismic events</p> <p> </p>

Simulation of Energy Consumption of Radiant Refrigeration Coatings on Buildings

In recent years, radiation refrigeration materials have developed rapidly, and a lot of research has been carried out from simulation and experimental testing. In this paper, the radiation refrigeration coating is applied to a small residential container building in Chengdu area. The experimental results show that the radiation refrigeration coating can reduce the indoor temperature and improve the indoor thermal environment. Combined with the numerical simulation analysis, it is found that the radiation refrigeration coating is suitable for the roof of the building, which can reduce the energy consumption of 2.47 kWh/ m2 per unit area per year.

An investigation of municipal housing permit data for representation of the Canadian housing stock in building codes analysis

Development of energy codes requires an appropriate building stock representation. To this end, information available within municipal construction permit records (e.g., dwelling type, floor and footprint area, foundation type, number of above-grade storeys, availability of an attached garage, and number of bedrooms) represents an untapped opportunity. However, these records are often stored in a semi-structured fashion with relevant information scattered within free-form text description fields, which necessitates text analytics. This paper introduces a text analytics-based method, employing the association rule mining, for information retrieval from permit records to support building stock modelling process; and the method is demonstrated with permit records from small residential buildings in seven major Canadian cities comprising over 240,000 unique entries. The analysis highlights that detached housing is the most common housing type and the average dwelling floor area was between 174 and 266 m2. Each permit record is associated with existing Canadian housing archetypes. It is found that mid-to-large-size detached archetypes are more common than smaller row or semi-detached archetypes. A building performance simulation-based investigation revealed that assuming an equal weight for each archetype, instead of using the distributions identified from the permit records, causes an underestimation of the housing stock's energy use by 36%.

Long-term energy performance of thermal caisson geothermal systems

In Canada, buildings account for a considerable portion of energy use and contribute heavily to Canada’s greenhouse gas (GHG) emissions. As such, a transition towards energy-efficient heating and cooling systems is important. Sustainable ground-source heat pumps (GSHPs) are one type of energy-efficient heating and cooling systems. But, they have high capital costs and often decline in efficiency over time. In this study, we further develop a phase change material (PCM)-based thermal caisson (TC) system, and extend a numerical algorithm previously developed in the same research group to assess the long-term energy performance of these systems. Dual-purpose and low-cost TCs not only provide structural support to a building, but also provide high efficiency geothermal heating and cooling, through ground heat exchanger U-tubes and embedded PCMs. Linear regression analyses are also performed to formulate how values of the coefficient of performance (COP) of TC systems change over time based on results from the literature and the current model. The results show that the long-term energy performance of TCs is significantly influenced by the use of a PCM, which can improve the long-term COP of GSHP systems, by 22% on average. For the small residential building investigated in this study, the capital cost and the net present value (NPV) of a TC system can be up to 50% and 32% lower, respectively, than the corresponding values for a conventional GSHP system. In addition, the TC system has a return on investment (ROI) of 65% which is significantly higher compared to the conventional GSHP system. Furthermore, over the heat pump system lifetime (assumed 20 years in this work), the CO2 emissions of the TC-based system are approximately 19% lower than conventional GSHP systems. Overall, the techniques used in this study can be extended and applied to larger buildings and potentially lead to greater energy savings for these buildings, if TCs are widely adopted in the building sector

Effect of bismuth oxide nanoparticle on the electromagnetic interference shielding and thermal stability of industrial waste based-geopolymer composites

Gold mine tailings, fly ash, and bagasse ash has been repurposed to produce geopolymer (GP) with enhanced electromagnetic interference shielding efficiency (EMI-SE) and high thermal property. GP has low shielding efficiency compared to concrete. Due to this, an appropriate filler must be incorporated into its matrix to enhance its EMI-SE. For this study, bismuth oxide nanomaterial (BiNP) was utilized as the additive filler. The percent content of BiNP was varied to evaluate its influence on the EMI-SE of GP. Morphology shows that Bi2O3 was embedded in the matrix of GP, and no new aluminu-phyllosilicate minerals were formed. This indicates that some minerals acted only as internal fillers in the matrix. Compressive strength shows synthesized GP composites were more than 20 MPa, with neat GP reaching the maximum strength. Moreover, the EMI-SE of neat GP was 21.2 dB for 20–4500 MHz range. This indicates that GP alone has sufficient characteristics to attenuate EMI radiation. Addition of 5%, 10% and 15% weight of BiNP improves EMI-SE by 4–10%, with 5% BiNP shown to be the optimum ratio. Lastly, the addition of BiNP improves the thermal stability of GP. This study shows that GP incorporated with Bi2O3 can be recommended for small-scale construction and small residential building.

THE EFFECT OF USING PHASE CHANGE MATERIALS AND EXAMINING THE ASPECT RATIO IN AN AIR-COOLED SYSTEM OF A PLATE BATTERY CONNECTED TO A SOLAR SYSTEM

Lithium-ion batteries are widely used in the electronics industry to store electrical energy. One of the challenges with these batteries is that they heat up during operation, which can damage the battery. For this reason, this paper simulates the cooling process of a plate-type (BTP) lithium-ion battery pack. To control the temperature of the battery (T-B), a laminar air flow and a phase change material (PCM) are used. The PCM is placed in a heat sink around the battery. This evaluation is performed temporarily for four different dimensions of the PCM pack. The hot outlet of this system is used to provide the thermal energy required for a small residential building (THE) at a mild temperature. The BTP was also simulated using COMSOL. The results show that the use of larger heat sinks can increase the maximum (MAX) and average (AVE) temperature of the battery. The minimum T-B occurs at different times for the smaller PCM heat sinks. Also, when using a heatsink with a larger PCM volume, it takes longer for the PCM to fully solidify. A BTP with 5 or 50 battery cells can provide up to 3% or 30% of the THE required for the building.

The effect of using phase change materials in solar panel cooling to provide green and sustainable energy of a building

The present study numerically investigates the use of solar energy for heating in a building using EnergyPlus and COMSOL. A solar panel with a size of 0.5 × 1 m was simulated. A rectangular chamber containing CaCl26H2O as a phase change material (PCM) was positioned below the solar panel. A pipe with an Al2O3-water nanofluid flow and fins was placed in the middle of the PCM chamber. The hot water outflow of the solar panel was employed to supply the hot water demand of a small residential building. Also, the amount of carbon dioxide production for this house in different months of the year for the house with and without solar thermal panel was compared. Furthermore, the panel temperature and melted PCM fraction below the panel were studied at different nanofluid flow velocities. It was found that a higher flow velocity (20 mm/s) led to a lower panel temperature than a lower velocity (5 mm/s). Thus, a higher nanofluid flow velocity would increase the fraction of energy demand supplied through the solar system during the day (up to 19.1%); however, a rise in the velocity at night diminished the energy fraction. In July, using a solar heating panel to supply hot water to the house reduced carbon dioxide emissions by 43%.

Residential Building Envelope Energy Retrofit Methods, Simulation Tools, and Example Projects: A Review of the Literature

As one of the biggest energy consumers, buildings are the focus of the energy conservation market, and the building envelope, which has the highest impact on heating and cooling loads, is one of the main targets in retrofit projects. Several materials, systems, methods, and simulation tools are used in these projects, and it is critical to understand the impact of these methods in different locations, their frequency of use, and the effectiveness of market-ready new solutions. In that context, it is necessary to review the energy conservation measures (ECMs) that are suitable for residential building envelope retrofitting, and that are commercially available or under research and development. This paper provides an overview of these ECMs. A literature review was conducted on different building envelope ECMs, including traditional and innovative energy retrofit methods, such as aerogel and phase change materials on opaque and transparent components of existing buildings. Results show that the most effective retrofit projects include bundles of ECMs, and the traditional ECMs can be as effective as more innovative solutions in terms of energy saving. Moreover, computer energy models were created for a typical residential building in the US for cold and warm climate zones to determine the impact of different retrofit approaches based on a sensitivity analysis. Results show that envelope ECMs have higher energy saving potentials in cold climate zones, of up to around 30%, and reducing the air infiltration has the highest impact in both cold and warm climate zones in a typical small residential building.

Implementation of Contactless Liquid Level Sensing

Usually, the arises to measure liquid levels in containers, in large industries; where large volumes of liquids are stored, in small scale industries and residential buildings in developing countries that sees many households implementing their own domestic water supply system. Measurements by humans may be influenced by sentiments, fatigues, lack of concentration, and so on, which has led to economic losses due lost liquid and wasted electric power. Therefore, researches have been directed toward development of automatic liquid level sensing technologies. This paper will assist instrumentation researchers to know the state of the art in level sensing technology, and practitioners in selecting the right kind of level sensors for a particular application.

Thermoeconomic and environmental evaluation of a combined heat, power, and distilled water system of a small residential building with water demand strategy

The most important challenges facing humans are global warming and lack to freshwater. Large-scale desalination has always been of interest, but producing freshwater using heat recovery in small-scale combined heat and power systems has not yet been sufficiently discussed. The small scale desalination is highly required, because it can use small scale recoverable waste heat from the micro/small scale power generators. Decentralized small scale desalination systems are more feasible and reliable than centralized big desalination systems for the time of crises such earthquake, war and terrorist attacks, and water loss reduction due to water transmission pipelines. In this research, a cycle is designed for simultaneous production of power, heat and freshwater in small scale for residential buildings. The power generator is a micro gas turbine by Capstone Company. The cycle feasibility is studied by energy, exergy, economic, and environmental criteria, and the design of the desalination is presented in details. The sizing of the system’s components is done according to the following water demand strategy. Evaluations show that the proposed system is feasible from thermodynamics, economic, and environmental viewpoints. The simulation is done by code generation in MATLAB software. The footprint area to install the small scale multi-stage flash desalination is 0.25 m2. The net present value is 25 million United States dollar with payback period of less than 2 years. It also reduces carbon dioxide about 39 tons/year.

A stochastic thermo-economic analysis of solar domestic hot-water systems in compliance with building energy code requirements: The case of Spain

Spanish residential buildings typically cover the required domestic hot-water renewable fraction regulated by building codes using solar thermal systems, typically through solutions based on flat-plate collectors and water storage tanks. For medium or large buildings (with high domestic hot-water demands), the energy savings produced by the solar system operation easily exceed the owning, operating, and maintenance costs, with its installation being highly advantageous under current energy prices. However, this situation is much less clear when small residential buildings are taken into consideration, as energy savings produced by solar domestic hot-water systems may not be sufficiently large to compensate for those costs, often operating below economically feasible levels. The energy savings associated with the operation of the solar systems were estimated using the simulation tool TRNSYS, using its output results as input data to conduct two different economic feasibility assessments (based on deterministic, and stochastic approaches). The deterministic analysis revealed that solar DHW-systems installed in small buildings with fewer than 5 apartments are not economically feasible. The stochastic economic analysis identified a wide probability range (between 70 and 90% of all the simulated cases) for economically feasible solar domestic hot-water systems, when they serve buildings with more than 48 apartments.

Improvements in the airtightness of housing in Richmond, British Columbia

Controlling air leakage through the building envelope remains a challenge, especially in light of the imperative to transition to a net-zero energy building sector and the increasing importance of indoor air quality during extreme weather events such as wildfires. The British Columbia Energy Step Code is a performance-based compliance option in the British Columbia Building Code which is intended to provide a transition pathway to net-zero energy ready construction by 2032. For small residential buildings, performance targets entail thresholds for the measured air leakage rate through the building envelope. This paper reports on the airtightness of the first 145 single- and two-family dwellings built under the Energy Step Code in Richmond, BC. Although the first phase of the implementation of the Energy Step Code in Richmond entailed no airtightness targets (only testing), results indicate improvement compared to the historical levels of airtightness in the region.

Effect of LCA Data Sources on GBRS Reference Values: The Envelope of an Italian Passive House

Scientific literature provides evidence that mitigating the effects of a building’s operation does not in itself ensure an overall improvement in its environmental performance. A Life Cycle Assessment (LCA) plays a key role in gauging the overall environmental performance of a building although several authors argue that the lack of LCA threshold values makes it difficult to compare design options or measure whether reduced impact targets are achieved. This has led the Green Building Rating Systems (GBRS) to include the LCA within their evaluation criteria and, in like Active House (AH), establish threshold values of the main impact categories to quantify the level of performance achieved. Since the reliability of the data sources is a crucial issue for applying the LCA method, the effectiveness of their implementation within the GBRS also strictly depends on the origin of the impact values. To quantify the extent to which the source affects the impacts calculated by the LCA threshold value in AH, the present study compared the outcomes of two assessments carried out in parallel using two different data sources: AH–LCA evaluation tool v.1.6 and the Environmental Product Declaration (EPD). A Passive House (PH)-compliant, small residential building was selected as a case study, as this is a standard that excels in ultra-low-energy performance. Moreover, given the crucial role that the envelope plays in the PH standard, the analysis was undertaken on the envelope of a PH-compliant building located in Northern Italy. To stress the influence of embedded effects in a Passive House, the assessment focused on the production and end-of-life stages of building materials. The comparison showed a relevant difference between the two scenarios for all the environmental indicators: e.g., deviations of 10% for Global Warming Potential, 20% for Acidification Potential and Eutrophication Potential, and 40–50% for Renewable Primary Energy.

Solar power based heating systems with electrical storage as alternative to fossil based systems for small residential buildings

Renewable energy is expected to replace thermal power by fossil fuel for reduction of green gas emission, air pollution and energy-security. Especially solar power generation is expected because it is got anywhere and its cost has reduced recently. But it is got only in the daytime on sunny days. Furthermore the amount, the time period it can get depends on seasons, weathers. Storage battery is essential for accumulating overpowered electricity and emitting it after sunset. The peak electricity demand is important factor to design electricity power plants. There are large electricity demands in summer and winter by air-conditioning. It is important to replace them by solar power with storage battery Building Research Institute in Japan has a demonstration house, which has solar power generator and storage battery combined system. The authors have measured how this system worked with air-conditioning electricity demand in summer and winter. And the authors applied these results to the actual electricity demand in Tokyo Metropolitan area. If solar power generator is combined with storage battery, it could cover air-conditioning cooling demand completely. In winter, peak electricity is high in morning and evening. So solar power could not mitigate electricity supplying demand in winter directly. But it is expected to supply electricity for a whole day, combined with storage battery.

LONG-SHORT SKIP CONNECTIONS IN DEEP NEURAL NETWORKS FOR DSM REFINEMENT

Abstract. Detailed digital surface models (DSMs) from space-borne sensors are the key to successful solutions for many remote sensing problems, like environmental disaster simulations, change detection in rural and urban areas, 3D urban modeling for city planning and management, etc. Traditional methodologies, e.g., stereo matching, used to generate photogrammetric DSMs from stereo imagery, usually deliver low-quality results due to the matching errors in homogeneous areas or the lack of information when observing the scene under different viewing angles. This makes the tasks related to building reconstruction very challenging since in most cases it is difficult to recognize the type of roofs, especially if overlaid with trees. This work represents a continuation of research regarding the automatic optimization of building geometries in photogrammetric DSMs with half-meter resolution and introduces an improved generative adversarial network (GAN) architecture which allows to reconstruct complete and detailed building structures without neglecting even low-rise urban constructions. The generative part of the network is constructed in a way that it simultaneously processes height and intensity information, and combines short and long skip connections within one architecture. To improve different aspects of the surface, several loss terms are used, the contributions of which are automatically balanced during training. The obtained results demonstrate that the proposed methodology can achieve two goals without any manual intervention: improve the roof surfaces by making them more planar and also recognize and optimize even small residential buildings which are hard to detect.

Thermomodernization of Historical Buildings with Residential Facades

Historic buildings, as well as much newer ones, with architecturally attractive facades, will not be thermomodernized from the outside, Because of their high value stands in the way. One such case is mentioned in this article, in which an analysis of external vertical partitions was carried out, in terms of heat and humidity in a small residential building located in southern Poland and built in 1930. The article describes a hygrothermal analysis of the above mentioned partitions, before and after thermomodernization, which should assess the legitimacy and effectiveness of using controversial methods of insulation of external building partitions from their internal sides. The article is a summary of a five-year observation and research of the object, after its thermomodernization in 2015. The analysis was focused on its vertical partitions.

Numerical analysis on flexural behaviour of GFRP sandwich roof panel with multilayer core material

In this study, the flexural performance of Glass Fibre Reinforced Polymer (GFRP) sandwich roof panel with multilayer polyurethane foam core was investigated using commercial FEM software ANSYS WORKBENCH. The GFRP sandwich panel is composed of thin GFRP face sheets at top and bottom infilled with Polyurethane (PU) foam core of two different densities. GFRP sandwich panels with different stacking sequences of the multilayer core was considered to determine the best sequence in which the different layers of core material can be laid on top of each other. The optimum panel size was obtained from parametric study conducted with number of GFRP plies and thickness of core as parameters. Alternatively, the flexural behaviour of GFRP sandwich panel with three different web core configurations were also studied, which includes trapezoidal shaped GFRP webs infilled with PU foam (Type 1), rhombus shaped GFRP webs infilled with PU foam (Type 2), and wave shaped GFRP webs infilled with PU foam (Type 3). Based on the finite element analysis, GFRP sandwich panel with Type 3 core configuration (wave shaped GFRP webs infilled with PU foam) with lesser deformation represented a feasible model to be used as a roofing panel for small residential buildings and prefabricated modular constructions.

Power Management in Hybrid Microgrid

This paper is representing power management in a hybrid microgrid. The hybrid microgrid consists of PV, wind, battery, and grid. The power management strategy is mentioned in islanding and grid-connected mode. In a grid-connected system, the grid converter has to monitor and manage the power to flow between microgrid and grid. The voltage shifting based droop control technique is used in DG for proper load sharing when two sources are connected in parallel. DG units in hybrid microgrid have two switching modes including droop control and maximum power tracking (MPPT). The operation of a hybrid microgrid is operated in different thee mode. The bus voltage is the main carrier to switching the mode of a hybrid microgrid. The power management algorithm for hybrid microgrid described here. This renewable-based hybrid microgrid model can be used for different aspects like small residential and commercial buildings. The feasibility and effectiveness of this strategy for hybrid microgrid running in various modes verified by simulation result.

Photovoltaic systems – types of installations, materials, monitoring and modeling - review

Photovoltaic systems have become a common solution for, both small residential buildings as well as large service buildings. When buildings are being designed, it is important to focus on the aspect of the object’s energy efficiency as lowering the energy consumption of a given facility is crucial. The article discusses the use of photovoltaic panels such as so-called BAPV (Building Applied Photovoltaics) and BIPV (Building Installed Photovoltaics) installations as well as photovoltaic thermal systems (PV/T), which generate both electricity and heat. The role of PV installation in so-called zero energy buildings and proposals for future research and solutions are also discussed.