scholarly journals Characterising the effects of wind-driven rain on the thermophysical performance of cavity walls by means of a Bayesian framework

2021 ◽  
Vol 2069 (1) ◽  
pp. 012053
Author(s):  
V Gori ◽  
V Marincioni ◽  
H Altamirano-Medina
Keyword(s):  
Energy Performance ◽  
Bayesian Framework ◽  
Mitigation Strategies ◽  
Cavity Wall ◽  
Water Penetration ◽  
Heat Effects ◽  
Dry Conditions ◽  
U Value ◽  
The Uk ◽  
Change Mitigation

Abstract Cavity wall is one of the most common construction types in temperate maritime climates, including the UK. However, water penetration may lead to damp within the structure, freeze-thaw damage at the outer surface and a reduction in thermal resistance. The magnitude of wetting effects on the energy performance of cavity walls is still unclear, with potentially significant implications for climate-change-mitigation strategies. This paper investigates the thermophysical performance of uninsulated and insulated cavity walls and its degradation as the element is wettened. Experiments were performed in a hygrothermal laboratory where two cavity-wall specimens (one of which coated with external waterproofing treatment) were tested under a high wind-driven rain exposure. Changes in the thermophysical performance between dry and wet conditions were evaluated through U-value testing and Bayesian inference. Substantial U-value increase was observed for wet uninsulated specimens (compared to dry conditions); conversely, closer U-value ranges were obtained when insulated with EPS grey beads. Moreover, latent-heat effects through the external masonry leaf of the untreated specimen were predicted by the Bayesian framework. Results suggest a negligible efficacy of waterproofing surface treatments as strategies for the reduction of heat transfer within the element, and possible effects of these agents on the evaporative and drying process.

Impact of roof shading on building energy performance in warm & humid climatic places of India

2020 ◽  
pp. 50-64
Author(s):  
Kuladeep Kumar Sadevi ◽  
Avlokita Agrawal
Keyword(s):  
Energy Consumption ◽  
Energy Conservation ◽  
Energy Performance ◽  
General Assumption ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Passive Cooling ◽  
Base Case ◽  
U Value ◽  
The Impact

With the rise in awareness of energy efficient buildings and adoption of mandatory energy conservation codes across the globe, significant change is being observed in the way the buildings are designed. With the launch of Energy Conservation Building Code (ECBC) in India, climate responsive designs and passive cooling techniques are being explored increasingly in building designs. Of all the building envelope components, roof surface has been identified as the most significant with respect to the heat gain due to the incident solar radiation on buildings, especially in tropical climatic conditions. Since ECBC specifies stringent U-Values for roof assembly, use of insulating materials is becoming popular. Along with insulation, the shading of the roof is also observed to be an important strategy for improving thermal performance of the building, especially in Warm and humid climatic conditions. This study intends to assess the impact of roof shading on building’s energy performance in comparison to that of exposed roof with insulation. A typical office building with specific geometry and schedules has been identified as base case model for this study. This building is simulated using energy modelling software ‘Design Builder’ with base case parameters as prescribed in ECBC. Further, the same building has been simulated parametrically adjusting the amount of roof insulation and roof shading simultaneously. The overall energy consumption and the envelope performance of the top floor are extracted for analysis. The results indicate that the roof shading is an effective passive cooling strategy for both naturally ventilated and air conditioned buildings in Warm and humid climates of India. It is also observed that a fully shaded roof outperforms the insulated roof as per ECBC prescription. Provision of shading over roof reduces the annual energy consumption of building in case of both insulated and uninsulated roofs. However, the impact is higher for uninsulated roofs (U-Value of 3.933 W/m2K), being 4.18% as compared to 0.59% for insulated roofs (U-Value of 0.33 W/m2K).While the general assumption is that roof insulation helps in reducing the energy consumption in tropical buildings, it is observed to be the other way when insulation is provided with roof shading. It is due to restricted heat loss during night.

scholarly journals Promoting Renewable Energy to Cope with Climate Change—Policy Discourse in Israel

2021 ◽  
Vol 13 (6) ◽  
pp. 3170
Author(s):  
Avri Eitan
Keyword(s):  
Climate Change ◽  
Renewable Energy ◽  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Climate Change Mitigation ◽  
Renewable Energies ◽  
Mitigation Strategies ◽  
Policy Discourse ◽  
Policy Makers ◽  
Change Mitigation

Evidence shows that global climate change is increasing over time, and requires the adoption of a variety of coping methods. As an alternative for conventional electricity systems, renewable energies are considered to be an important policy tool for reducing greenhouse gas emissions, and therefore, they play an important role in climate change mitigation strategies. Renewable energies, however, may also play a crucial role in climate change adaptation strategies because they can reduce the vulnerability of energy systems to extreme events. The paper examines whether policy-makers in Israel tend to focus on mitigation strategies or on adaptation strategies in renewable energy policy discourse. The results indicate that despite Israel’s minor impact on global greenhouse gas emissions, policy-makers focus more on promoting renewable energies as a climate change mitigation strategy rather than an adaptation strategy. These findings shed light on the important role of international influence—which tends to emphasize mitigation over adaptation—in motivating the domestic policy discourse on renewable energy as a coping method with climate change.

scholarly journals A Fundamental Study on the Development of New Energy Performance Index in Office Buildings

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2064
Author(s):  
Jin-Hee Kim ◽  
Seong-Koo Son ◽  
Gyeong-Seok Choi ◽  
Young-Tag Kim ◽  
Sung-Bum Kim ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Requirement ◽  
Energy Performance ◽  
Office Buildings ◽  
Light Transmittance ◽  
Wall Structure ◽  
Fundamental Study ◽  
Future Studies ◽  
U Value ◽  
The Impact

Recently, there have been significant concerns regarding excessive energy use in office buildings with a large window-to-wall ratio (WWR) because of the curtain wall structure. However, prior research has confirmed that the impact of the window area on energy consumption varies depending on building size. A newly proposed window-to-floor ratio (WFR) correlates better with energy consumption in the building. In this paper, we derived the correlation by analyzing a simulation using EnergyPlus, and the results are as follows. In the case of small buildings, the results of this study showed that the WWR and energy requirement increase proportionally, and the smaller the size is, the higher the energy sensitivity will be. However, results also confirmed that this correlation was not established for buildings approximately 3600 m2 or larger. Nevertheless, from analyzing the correlation between the WFR and the energy requirements, it could be deduced that energy required increased proportionally when the WFR was 0.1 or higher. On the other hand, the correlation between WWR, U-value, solar heat gain coefficient (SHGC), and material property values of windows had little effect on energy when the WWR was 20%, and the highest effect was seen at a WWR of 100%. Further, with an SHGC below 0.3, the energy requirement decreased with an increasing WWR, regardless of U-value. In addition, we confirmed the need for in-depth research on the impact of the windows’ U-value, SHGC, and WWR, and this will be verified through future studies. In future studies on window performance, U-value, SHGC, visible light transmittance (VLT), wall U-value as sensitivity variables, and correlation between WFR and building size will be examined.

Net zero carbon: Energy performance targets for offices

2021 ◽  
Vol 42 (3) ◽  
pp. 349-369
Author(s):  
Robert Cohen ◽  
Karl Desai ◽  
Jennifer Elias ◽  
Richard Twinn
Keyword(s):  
Energy Efficiency ◽  
Minimum Energy ◽  
Energy Performance ◽  
Consultation Process ◽  
Net Zero ◽  
Extensive Consultation ◽  
Operational Energy ◽  
Legislative Framework ◽  
Zero Carbon ◽  
The Uk

The UKGBC Net Zero Carbon Buildings Framework was published in April 2019 following an industry task group and extensive consultation process. The framework acts as guidance for achieving net zero carbon for operational energy and construction emissions, with a whole life carbon approach to be developed in the future. In consultation with industry, further detail and stricter requirements are being developed over time. In October 2019, proposals were set out for industry consultation on minimum energy efficiency targets for new and existing commercial office buildings seeking to achieve net zero carbon status for operational energy today, based on the performance levels that all buildings will be required to achieve by 2050. This was complemented by modelling work undertaken by the LETI network looking into net zero carbon requirements for new buildings. In January 2020 UKGBC published its guidance on the levels of energy performance that offices should target to achieve net zero and a trajectory for getting there by 2035. This paper describes the methodology behind and industry perspectives on UKGBC’s proposals which aim to predict the reduction in building energy intensity required if the UK’s economy is to be fully-powered by zero carbon energy in 2050. Practical application: Many developers and investors seeking to procure new commercial offices or undertake major refurbishments of existing offices are engaging with the ‘net zero carbon’ agenda, now intrinsic to the legislative framework for economic activity in the UK. A UKGBC initiative effectively filled a vacuum by defining a set of requirements including energy efficiency thresholds for commercial offices in the UK to be considered ‘net zero carbon’. This paper provides all stakeholders with a detailed justification for the level of these thresholds and what might be done to achieve them. A worked example details one possible solution for a new office.

Does tax policy fit in the portfolio of COVID-19 responses?

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kerrie Sadiq ◽  
Richard Krever
Keyword(s):  
Tax Policy ◽  
Value Added ◽  
Mitigation Strategies ◽  
Income Support ◽  
Policy Reforms ◽  
Content Type ◽  
Goods And Services ◽  
Policy Responses ◽  
Tax Regimes ◽  
The Uk

Purpose Tax policymakers are currently navigating a path through a delicate dialectic of macro- and micro-level policy responses to the economic dislocation of the COVID-19 pandemic. The purpose of this paper is to examine initial tax measures that are aimed at helping taxpayers needing liquidity, solvency and income support. Design/methodology/approach This study undertakes a review of key tax policy responses of six jurisdictions across the globe that have similar tax regimes and virus mitigation strategies (albeit with different outcomes). Key initiatives implemented from February to April 2020 by Australia, Canada, New Zealand, Singapore, South Africa and the UK are examined. Findings This study indicates that tax concessions are a crude and mostly ineffective way of assisting individuals and enterprises in difficulty. In the longer term, if the crisis prompts desirable reforms such as extending the recognition of tax losses, the income tax system will emerge fairer and more efficient. Practical implications An investigation of the short-term reforms announced relating to asset write-offs, tax deferral, tax losses and goods and services tax/value-added tax rates in light of the liquidity, income support and stimulus objectives shows that in some cases the policies may have been misguided. The findings can be used by policymakers as the basis for designing better targeted alternative non-tax responses. Originality/value Jurisdictional responses to tax policy reforms during a modern period of significant economic dislocation have yet to be documented in the literature. Specifically, this paper highlights the limitations of tax policy initiatives as a response to financial hardship.

Global forest products trade model.

2021 ◽  
pp. 110-141
Author(s):  
Prakash Nepal ◽  
Joseph Buongiorno ◽  
Craig M. T. Johnston ◽  
Jeffrey Prestemon ◽  
Jing-gang Guo
Keyword(s):  
Climate Change ◽  
Policy Analysis ◽  
Mathematical Formulation ◽  
Forest Products ◽  
Mitigation Strategies ◽  
Forest Sector ◽  
Analysis Tool ◽  
Trade Model ◽  
Forest Industries ◽  
Change Mitigation

Abstract This chapter introduces the Global Forest Products Model (GFPM). The general model structure and the mathematical formulation of the GFPM are provided and key differences and similarities to the modeling approaches developed in the previous chapters are highlighted. The usefulness of the GFPM as a forest sector tool for policy analysis is illustrated by summarizing its applications in a wide array of past and ongoing studies. These studies are summarized under four representative groups: (i) forest sector outlook studies; (ii) studies evaluating the consequences of tariff and non-tariff barriers on the international trade of forest products; (iii) studies projecting the impacts of climate change and forest-based climate change mitigation strategies on forests and forest industries; and (iv) other studies dealing with other important questions, such as the effects of the rise in global planted forest area, illegal harvests, and invasive species. Some of the limitations of GFPM, ways to mitigate these limitations, and its overall usefulness as a forest sector policy analysis tool are also examined.

scholarly journals Heterogeneous reaction of HO<sub>2</sub> with airborne TiO<sub>2</sub> particles and its implication for climate change mitigation strategies

2017 ◽  
Author(s):  
Daniel R. Moon ◽  
Giorgio S. Taverna ◽  
Clara Anduix-Canto ◽  
Trevor Ingham ◽  
Martyn P. Chipperfield ◽  
...  
Keyword(s):  
Transport Model ◽  
Heterogeneous Reaction ◽  
Three Dimensional ◽  
Mitigation Strategies ◽  
Heterogeneous Reactions ◽  
Chemical Transport Model ◽  
Flow Tube ◽  
Tio2 Particles ◽  
The Impact ◽  
Change Mitigation

Abstract. One geoengineering mitigation strategy for global temperature rises resulting from the increased concentrations of greenhouse gases is to inject particles into the stratosphere to scatter solar radiation back to space, with TiO2 particles emerging as a possible candidate. Uptake coefficients of HO2, γ(HO2), onto sub-micrometre TiO2 particles were measured at room temperature and different relative humidities (RH) using an atmospheric pressure aerosol flow tube coupled to a sensitive HO2 detector. Values of γ(HO2) increased from 0.021 ± 0.001 to 0.036 ± 0.007 as the RH was increased from 11 % to 66 %, and the increase in γ(HO2) correlated with the number of monolayers of water surrounding the TiO2 particles. The impact of the uptake of HO2 onto TiO2 particles on stratospheric concentrations of HO2 and O3 was simulated using the TOMCAT three-dimensional chemical transport model. The model showed that by injecting the amount of TiO2 required to achieve the same cooling effect as the Mt. Pinatubo eruption, heterogeneous reactions between HO2 and TiO2 would have a negligible effect on stratospheric concentrations of HO2 and O3.

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