Search

Accurate knowledge of solar radiation data or its estimation is crucial to maximize the benefits derived from the Sun. In this context, many sectors are re-evaluating their investments and plans to increase profit margins in line with sustainable development based on knowledge and estimation of solar radiation. This scenario has drawn the attention of researchers to the estimation and measurement of solar radiation with a low level of error. Various types of models, such as empirical models, time series, artificial intelligence algorithms and hybrid models, for estimating and measuring solar radiation have been continuously developed in the literature. In general, these models require atmospheric, geographical, climatic and historical solar radiation data from a specific region for accurate estimation. Each analysis model has its advantages and disadvantages when it comes to estimating solar radiation and, depending on the model, the results for one region may be better or worse than for another. Furthermore, it has been observed that an input parameter that significantly improves the model's performance in one region can make it difficult to succeed in another. The research gaps, challenges and future directions in terms of solar radiation estimation have substantial impacts, but regardless of the model, in situ measurements and commercially available equipment consistently influence solar radiation calculations and, subsequently, simulations or estimates. This article aims to exemplify, through a case study in a multi-family residential building located in Viana do Castelo, a city in the north of Portugal, the difficulties of capturing the spectrum of radiations that make up the total radiation that reaches the measuring equipment or site. Three pieces of equipment are used—a silicon pyranometer, a thermopile pyranometer and a solar meter—on the same day, in the same place, under the same meteorological conditions and with the same measurement method. It is found that the thermopile pyranometer has superior behavior, as it does not oscillate as much with external factors such as the ambient temperature, which influence the other two pieces of equipment. However, due to the different assumptions of the measurement models, the various components of the measurement site make it difficult to obtain the most accurate and reliable results in most studies. Despite the advantages of each model, measurement models have gained prominence in terms of the ease of use and low operating costs rather than the rigor of their results. [ABSTRACT FROM AUTHOR]

This study presents an approach to determine the extent of renovation interventions required for existing Dutch dwellings aiming to transition to lower-temperature district heating (DH) systems. The proposed method is applied to a typical intermediate terraced house built before 1945 in the Netherlands, and it consists of two steps: first, assessing the potential of a dwelling to be heated with a lower temperature supply from DH systems and subsequently developing and evaluating alternative renovation solutions if necessary. This study defines a set of criteria for evaluating the readiness of a dwelling for lower-temperature heating (LTH), considering energy efficiency and thermal comfort as non-compensatory criteria. The application of the approach reveals that the case study dwelling is presently unsuitable for a medium-temperature (70/50 °C) and low-temperature (55/35 °C) supply compared to a high-temperature supply (90/70 °C), thus requiring energy renovations. Furthermore, this study indicates that moderate intervention levels are required for the dwelling to be lower-temperature-ready in both supply temperature goals. These interventions include strategies and measures that upgrade the building envelope to the minimum insulation levels stipulated by the Dutch Building Decree, improve airtightness, and replace existing radiators with low-temperature radiators. By systematically narrowing down renovation options, this approach aids in simplifying the decision-making process for selecting renovations for heating dwellings with LTH through DH systems, which could reduce stakeholders' decision paralysis. [ABSTRACT FROM AUTHOR]

How to analyse the omissions of thermal regulations and evaluate methodologies that provide building execution or thermal certificates that do not correspond to reality and usually incur costs? We can start by analysing different simulation methods and shading calculations that provide solar gains and shadow optimisation. After evaluating how the regulations define the calculation assumptions and how this calculation is performed, the discrepancies (simplifications) that the regulations allow or ignore are presented, and it is exemplified using two case studies. Using the Portuguese regulation as a case study, it leads to incorrect conclusions or assumptions due to unequal access to solar radiation or the shading factor calculation that experiences the omission of angles or time periods. Therefore, the aim is to propose a calculation process (premises) that minimises the discrepancies between simulation (optimisation strategy) and reality (applicability of strategies) for sustainable output. [ABSTRACT FROM AUTHOR]

Decisions made at early stages of the design are of the utmost importance for the energy-efficiency of buildings. Wrong decisions and design failures related to a building's general layout, shape, façade transparency or orientation can increase the operational energy tremendously. These failures can be avoided in advance through simple changes in the design. Using extensive parametric energy simulations by DesignBuilder, this paper investigates the impact of geometric factors for the energy-efficiency of high-rise office buildings in three climates contexts: Amsterdam (Temperate), Sydney (Sub-tropical) and Singapore (Tropical). The investigation is carried out on 12 plan shapes, 7 plan depths, 4 building orientations and discrete values for window-to-wall ratio. Among selected options, each sub-section determines the most efficient solution for different design measures and climates. The optimal design solution is the one that minimises, on an annual basis, the sum of the energy use for heating, cooling, electric lighting and fans. The results indicate that the general building design is an important issue to consider for high-rise buildings: they can influence the energy use up to 32%. For most of the geometric factors, the greatest difference between the optimal and the worst solution occurs in the sub-tropical climate, while the tropical climate is the one that shows the smallest difference. In case of the plan depth, special attention should be paid in the case of a temperate climate, as the total energy use can increase more than in other climates. Regarding energy performance, the following building geometry factors have the highest to lowest influence: building orientation, plan shape, plan depth, and window-to-wall ratio. [ABSTRACT FROM AUTHOR]

The production, processing, and transportation of food, in particular animal-based products, imposes great environmental burden on the planet. The current food supply system often constitutes a considerable part of the total carbon emissions of urban communities in industrialised cities. Urban food production (UFP) is a method that can potentially diminish food emissions. In parallel, a shift towards a predominantly plant-based diet that meets the nutritional protein intake is an effective method to curtail carbon emissions from food. Considering the high land use associated with the production of animal-based products, such a shift will prompt a community food demand that is more inclined to be satisfied with local production. Therefore, during the design process of a future low-carbon city, the combined application of both methods is worth exploring. This work introduces, describes, and demonstrates the diet shift component of the FEWprint platform, a user friendly UFP assessment platform for designers that is constructed around the broader three-pronged strategy of evaluation, shift, and design. For three neighborhoods, in Amsterdam, Belfast, and Detroit, the contextual consumption and country-specific environmental footprint data are applied to simulate a theoretical community-wide diet shift from a conventional to a vegan diet, whilst maintaining protein intake equilibrium. The results show that in total terms, the largest carbon mitigation potential awaits in Detroit (−916 kg CO2eq/cap/year), followed by Belfast (−866 kg) and Amsterdam (−509 kg). In relative terms, the carbon reduction potential is largest in Belfast (−25%), followed by Amsterdam (−15%) and Detroit (−7%). The FEWprint can be used to generate preliminary figures on the carbon implications of dietary adaptations and can be employed to give a first indication of the potential of UFP in urban communities. [ABSTRACT FROM AUTHOR]

The municipality of Amsterdam has set stringent carbon emission reduction targets: 55% by 2030 and 95% by 2050 for the entire metropolitan area. One of the key strategies to achieve these goals entails a disconnection of all households from the natural gas supply by 2040 and connecting them to the existing city-wide heat grid. This paper aims to demonstrate the value of considering local energy potentials at the city block level by exploring the potential of a rooftop greenhouse solar collector as a renewable alternative to centralized district heating. An existing supermarket and an ATES component complete this local energy synergy. The thermal energy balance of the three urban functions were determined and integrated into hourly energy profiles to locate and quantify the simultaneous and mismatched discrepancies between energy excess and demand. The excess thermal energy extracted from one 850 m2 greenhouse can sustain up to 47 dwellings, provided it is kept under specific interior climate set points. Carbon accounting was applied to evaluate the system performance of the business-as-usual situation, the district heating option and the local system. The avoided emissions due to the substitution of natural gas by solar thermal energy do not outweigh the additional emissions consequential to the fossil-based electricity consumption of the greenhouse's crop growing lights, but when the daily photoperiod is reduced from 16 h to 12 h, the system performs equally to the business-as-usual situation. Deactivating growth lighting completely does make this local energy solution carbon competitive with district heating. This study points out that rooftop greenhouses applied as solar collectors can be a suitable alternative energy solution to conventional district heating, but the absence of growing lights will lead to diminished agricultural yields. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) are materials that can store large amounts of heat during their phase transition from solid to liquid without a significant increase in temperature. While going from liquid to solid this heat is again released. As such, these materials can play an important role in future energy-efficient buildings. If applied in facades as part of a thermal buffer strategy, e.g., capturing and temporarily storing solar energy in so-called Trombe walls, the PCMs are exposed to high solar radiation intensities, which may easily lead to issues of overheating. This paper therefore investigates the melting process of PCM and arrives at potential solutions for countering this overheating phenomenon. This study uses the simulation program Comsol to investigate the heat transfer through, melting of and fluid flow inside a block of PCM (3 × 20 cm2) with a melting temperature of around 25 °C. The density, specific heat and dynamic viscosity of the PCM are modeled as a temperature dependent variable. The latent heat of the PCM is modeled as part of the specific heat. One side of the block of PCM is exposed to a heat flux of 300 W/m2. The simulations show that once part of the PCM has melted convection arises transporting heat from the bottom of the block to its top. As a result, the top heats up faster than the bottom speeding up the melting process there. Furthermore, in high columns of PCM a large temperature gradient may arise due to this phenomenon. Segmenting a large volume of PCM into smaller volumes in height limits this convection thereby reducing the temperature gradient along the height of the block. Moreover, using PCMs with different melting temperature along the height of a block of PCM allows for controlling the speed with which a certain part of the PCM block starts melting. Segmenting the block of PCM using PCMs with different melting temperature along its height was found to give the most promising results for minimizing this overheating effect. Selecting the optimal phase change temperatures however is critical in that case. [ABSTRACT FROM AUTHOR]

This article sheds light on the materialization and operation of residential partitioning wall components in relation to circular and flexible performance. The hypothesis is twofold: (1) A stronger integration of materialization and operation aspects is indispensable in establishing sustainable value-models, and (2) recent innovations, concerning the reversibility of material connections, will help disrupting the status-quo in that respect. Attention is drawn to renewable natural fibre composites (NFC), reversible adhesives, and biodegradable insulation materials. After a background sketch regarding the notion of time, change, and material circularity in design and planning, the housing challenge in the Amsterdam metropolitan area (AMA, the Netherlands) is described. Next, a design conceptualization stage is introduced, informed by two methods and tools in particular: Circ-Flex assessment, and activity-based spatial material flow analysis. Results of the conceptualization stage are presented regarding materialization and operation, culminating in Circ-Flex partitioning components, more specifically: Side panels and insulation. It was found that NFC can tackle current issues relating, most prominently, to circularity performance. Associated modifications in the value-chain occur, above all, in raw material sourcing, manufacturing, reutilization logistics, and data-sharing. The outcomes are valid for multiple building components other than indoor partitioning, such as kitchens and furniture, but also insulation—and interior side-sheeting—of walls and roofs in energy-renovations. [ABSTRACT FROM AUTHOR]

This paper addresses the connection between circular building design and residential health and well-being. The general research objective is to determine assessment criteria for the performance of indoor partitioning products in a circular model. The overarching aim is to establish a more integrated and inclusive approach to the transition from linear to circular built environments. This ties in with recent calls for a more comprehensive evidence-base to better inform the policy debate, in the light of interrelated Sustainable Development Goals. The paper emphasises the operational level, looking closer at the actual performance of circular economy implementation, providing more grip on performance indicators of infill components in circular applications, specifically partition walls. Next to partitioning one can think of other components in the infill domain, such as kitchens, bathrooms and mechanical, electrical, plumbing installations. After a brief background sketch, a literature review is reported regarding indoor environmental quality and indoor air quality in general and the linkage with circular and flexible building (products) in particular. Next, an analysis is made of three assessment schemes that address the operational level. Subsequently, several criteria are synthesized and tested. It was shown that the assessment schemes have overlapping and complementary features that, in unison, provide a solid basis for an integrated assessment of circularity potential and health impact of infill products. The test-case helped to pinpoint generic, as well as case-specific, learning points. The interface between product performance and building performance over time remains a grey zone, insufficiently covered by current criteria. More stringent coordination efforts are essential to safeguard circularity potential and healthy living environments pre-use, post-use and not least in-use. [ABSTRACT FROM AUTHOR]

Circular building has gained considerable attention in the Netherlands during the past decade. It is rooted in concepts such as circular economy (CE) and Cradle-to-Cradle (C2C®), accentuating the closing and coupling of material loops to establish effective and efficient resource flows. Moreover, those concepts adhere to a systemic, holistic worldview, incorporating multiple flows and values. Although social aspects, such as health, wellbeing, and social inclusiveness, are generally part of circular building principles, specific benefits for end-users are not. This paper explores the synergistic potential of circular and flexible (Circ-Flex) criteria from the perspective of enhanced control and convenience for residents. The hypothesis is that without integrating the user domain, replicability of circular building concepts on a larger residential scale cannot be done in a truly sustainable manner. The paper is structured around two objectives: (1) further identifying the relationship between flexible and circular building; and (2) exploring the impact of circular, flexible building concepts and practices for the users of multi-family housing, specifically regarding interior partitioning. The research follows a mixed-mode methodology comprising of literature review, case study, expert consultations and a quick-scan assessment. Eleven Circ-Flex criteria are explored, grouped in three categories: flexibility capacity, circularity capacity, and user capacity. These criteria are applied to two partitioning variants, whilst exploring the performance regarding material circulation and user benefits. [ABSTRACT FROM AUTHOR]