Building envelope and energy demand in retrofitting office

Building envelopes have a significant role in the protection of interiors against weather conditions. While wind, rain barriers and barriers against excessive heat gains were constructed from insufficient elements in the past, the current requirements for envelope functions are different. New materials and technologies allow for more complex design and evaluation of parameters in regard to the needs of occupants and economical interior performance. This paper is focused on the daylighting solutions inside lit office space in which renovation of the lighting system is expected. Several retrofit scenarios based on window shading variations and lighting systems are investigated. Achieved results are evaluated from the point of view of energy demand. The integrative multi-platform tool, the Lighting Retrofit Adviser (LRA) is applied to calculate energy renovation preferences and to accept decision.

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Improved Human Thermal Comfort with Indoor PCM-Enhanced Tiles in Living Spaces in the Arabian Gulf

E3S Web of Conferences ◽

10.1051/e3sconf/20185704001 ◽

2018 ◽

Vol 57 ◽

pp. 04001 ◽

Cited By ~ 1

Author(s):

Albert Al Touma ◽

Djamel Ouahrani

Keyword(s):

Thermal Comfort ◽

Energy Demand ◽

Residential Buildings ◽

Arabian Gulf ◽

Weather Conditions ◽

Building Envelope ◽

Human Thermal Comfort ◽

Outdoor Environments ◽

Radiant Temperature ◽

Cooling Energy Demand

Al-Majlis is the living space in residential buildings of the Arabian Gulf, and is where occupants spend most of their time. For this reason, the human thermal comfort in this space is of extreme importance and is often compromised due to hot outdoor weather conditions. In contrast with many thermal discomfort mitigation methods in outdoor environments, which become unadvisable in indoor spaces, this study investigates the effect of adding PCM-enhanced tiles to portions of the indoor envelope on the occupant’s thermal comfort and the space cooling energy demand. A simulation model of a space with tight building envelope in Qatar was developed on EnergyPlus with and without the addition of PCM-enhanced tiles. The selected country is a representative location of the Arabian Gulf. Considering different occupant’s positions, the addition of the tiles with PCM on their back was found to moderate the mean radiant temperature, operative temperature, Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD), all of which signify an improvement in the human thermal comfort. Lastly, this change in the indoor envelope was found to save 3.3% of the space daily thermal cooling energy demand during one harsh summer representative day.

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Energy Renovation of Buildings the Skin of a Building 70’s Housing Developments in Barcelona Montbau’s Housing Developments Renovation

The Open Construction and Building Technology Journal ◽

10.2174/1874836801711010027 ◽

2017 ◽

Vol 11 (1) ◽

pp. 27-64

Author(s):

Josep M. Rieradevall i Pons ◽

Jaume Avellaneda i Diaz Grande ◽

Jaume Roset i Calzada

Keyword(s):

Internal Energy ◽

Energy Demand ◽

Energy Savings ◽

Weather Conditions ◽

Building Envelope ◽

Economic Costs ◽

Building Projects ◽

Housing Developments ◽

Heating And Cooling ◽

Different Characteristics

This study, considering the current conditions of our planet, proposes to analyze how efficient is to renovate building skins to meet energy, economic, and CO2 emission criteria. A building envelope is the part of a building that is most exposed to weather conditions and therefore it has an impact on the internal energy demand of its inhabitants so that they can comfortably there. Studying building skins and their status in terms of energy, economic costs, and CO2 emissions will allow renovation to produce benefits in the medium and long-term. This study was conducted in the neighborhood of Montbau, a housing development of around 30 buildings, each with different characteristics, built in the 70’s and currently having energy losses through their skins, which results in a high demand of internal energy for heating and cooling purposes, in addition to doubled emission of CO2e released into the atmosphere. Improvements are proposed to adapt the conditions of these buildings. Two solutions are proposed in addition to evaluating energy costs caused by CO2e emissions and any other economic costs year 2012. Other studies analyze the behavior of buildings already implementing such solutions and their corresponding energy, emission, and economic reductions. The importance of such studies lays on the need to analyze options such as renovation instead of considering demolition as an alternative, and to suggest the future building of housing developments in pro of the sustainability of our planet and offer an alternative for a sustainable future, housing and shelter under optimal conditions. The figures herein offer solid results in terms of expenses, costs and energy savings, as well as the reduction of CO2 emissions released into the atmosphere. The graphs and tables here contained offer a clear reading and suggest topics for further research and even for starting up building projects, both locally and worldwide.

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Effectiveness of Flood Protection Project Valuation Methods

Olsztyn Economic Journal ◽

10.31648/oej.3152 ◽

2015 ◽

Vol 10 (3) ◽

pp. 275-289

Author(s):

Tadeusz Liziński ◽

Marcin Bukowski ◽

Anna Wróblewska

Keyword(s):

Essential Element ◽

Weather Conditions ◽

Point Of View ◽

Flood Protection ◽

Costs And Benefits ◽

Protection Measures ◽

Investment Projects ◽

Market Values ◽

Project Valuation ◽

The Subject

Projects for flood protection are increasingly the subject of investment projects in the field of water management. This is related to the increasing frequency of worldwide threats caused by extreme weather conditions, including extremely high rainfall causing floods. Technical and nontechnical flood protection measures are also increasing in importance. In the decision-making process, it is necessary to take into account both the costs and benefits of avoiding losses, including an analysis of social benefits, whose valuation of non-market goods is an essential element. A comprehensive account of projects in the field of flood protection based on the estimated costs and benefits of the investment allows the economic efficiency from a general social point of view to be determined. Previous evaluations of the effectiveness of investment projects have mainly taken into account only categories and market values. The aim of the article is to identify the possibilities to expand the values of non-market assessments and categories formulated on the basis of the theoretical economics of the environment.

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Overheating Risk and Energy Demand of Nordic Old and New Apartment Buildings during Average and Extreme Weather Conditions under a Changing Climate

Applied Sciences ◽

10.3390/app11093972 ◽

2021 ◽

Vol 11 (9) ◽

pp. 3972

Author(s):

Azin Velashjerdi Farahani ◽

Juha Jokisalo ◽

Natalia Korhonen ◽

Kirsti Jylhä ◽

Kimmo Ruosteenoja ◽

...

Keyword(s):

Climate Change ◽

Energy Demand ◽

Energy Use ◽

Residential Buildings ◽

Weather Conditions ◽

Extreme Weather ◽

Living Room ◽

Extra Energy ◽

Cooling Unit ◽

Indoor Conditions

The global average air temperature is increasing as a manifestation of climate change and more intense and frequent heatwaves are expected to be associated with this rise worldwide, including northern Europe. Summertime indoor conditions in residential buildings and the health of occupants are influenced by climate change, particularly if no mechanical cooling is used. The energy use of buildings contributes to climate change through greenhouse gas emissions. It is, therefore, necessary to analyze the effects of climate change on the overheating risk and energy demand of residential buildings and to assess the efficiency of various measures to alleviate the overheating. In this study, simulations of dynamic energy and indoor conditions in a new and an old apartment building are performed using two climate scenarios for southern Finland, one for average and the other for extreme weather conditions in 2050. The evaluated measures against overheating included orientations, blinds, site shading, window properties, openable windows, the split cooling unit, and the ventilation cooling and ventilation boost. In both buildings, the overheating risk is high in the current and projected future average climate and, in particular, during exceptionally hot summers. The indoor conditions are occasionally even injurious for the health of occupants. The openable windows and ventilation cooling with ventilation boost were effective in improving the indoor conditions, during both current and future average and extreme weather conditions. However, the split cooling unit installed in the living room was the only studied solution able to completely prevent overheating in all the spaces with a fairly small amount of extra energy usage.

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Design and Field Validation of a Low Power Wireless Sensor Node for Structural Health Monitoring

Sensors ◽

10.3390/s21041050 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1050

Author(s):

Federico Zanelli ◽

Francesco Castelli-Dezza ◽

Davide Tarsitano ◽

Marco Mauri ◽

Maria Laura Bacci ◽

...

Keyword(s):

Low Power ◽

Sensor Node ◽

Weather Conditions ◽

Point Of View ◽

Design Stage ◽

Monitoring Systems ◽

Wireless Sensor Node ◽

Process Data ◽

Fatigue Life Estimation ◽

Remaining Fatigue Life

Smart monitoring systems are currently gaining more attention and are being employed in several technological areas. These devices are particularly appreciated in the structural field, where the collected data are used with purposes of real time alarm generation and remaining fatigue life estimation. Furthermore, monitoring systems allow one to take advantage of predictive maintenance logics that are nowadays essential tools for mechanical and civil structures. In this context, a smart wireless node has been designed and developed. The sensor node main tasks are to carry out accelerometric measurements, to process data on-board, and to send wirelessly synthetic information. A deep analysis of the design stage is carried out, both in terms of hardware and software development. A key role is played by energy harvesting integrated in the device, which represents a peculiar feature and it is thanks to this solution and to the adoption of low power components that the node is essentially autonomous from an energy point of view. Some prototypes have been assembled and tested in a laboratory in order to check the design features. Finally, a field test on a real structure under extreme weather conditions has been performed in order to assess the accuracy and reliability of the sensors.

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Optimal Planning and Operation of a Residential Energy Community under Shared Electricity Incentives

Energies ◽

10.3390/en14082045 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2045

Author(s):

Pierpaolo Garavaso ◽

Fabio Bignucolo ◽

Jacopo Vivian ◽

Giulia Alessio ◽

Michele De Carli

Keyword(s):

Renewable Energy ◽

Power Distribution ◽

Energy Demand ◽

Renewable Energy Sources ◽

Energy System ◽

Distribution Networks ◽

Building Envelope ◽

Net Energy ◽

Technical Equipment ◽

Optimal Planning

Energy communities (ECs) are becoming increasingly common entities in power distribution networks. To promote local consumption of renewable energy sources, governments are supporting members of ECs with strong incentives on shared electricity. This policy encourages investments in the residential sector for building retrofit interventions and technical equipment renovations. In this paper, a general EC is modeled as an energy hub, which is deemed as a multi-energy system where different energy carriers are converted or stored to meet the building energy needs. Following the standardized matrix modeling approach, this paper introduces a novel methodology that aims at jointly identifying both optimal investments (planning) and optimal management strategies (operation) to supply the EC’s energy demand in the most convenient way under the current economic framework and policies. Optimal planning and operating results of five refurbishment cases for a real multi-family building are found and discussed, both in terms of overall cost and environmental impact. Simulation results verify that investing in building thermal efficiency leads to progressive electrification of end uses. It is demonstrated that the combination of improvements on building envelope thermal performances, photovoltaic (PV) generation, and heat pump results to be the most convenient refurbishment investment, allowing a 28% overall cost reduction compared to the benchmark scenario. Furthermore, incentives on shared electricity prove to stimulate higher renewable energy source (RES) penetration, reaching a significant reduction of emissions due to decreased net energy import.

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Energy Performance Assessment of Innovative Building Solutions Coming from Construction and Demolition Waste Materials

Materials ◽

10.3390/ma14051226 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1226

Author(s):

Beatriz Fraga-De Cal ◽

Antonio Garrido-Marijuan ◽

Olaia Eguiarte ◽

Beñat Arregi ◽

Ander Romero-Amorrortu ◽

...

Keyword(s):

Thermal Insulation ◽

Energy Demand ◽

Energy Savings ◽

Flow Analysis ◽

Weather Conditions ◽

Energy Performance ◽

Construction And Demolition Waste ◽

The European Union ◽

Demolition Waste ◽

The Impact

Prefabricated solutions incorporating thermal insulation are increasingly adopted as an energy conservation measure for building renovation. The InnoWEE European project developed three technologies from Construction and Demolition Waste (CDW) materials through a manufacturing process that supports the circular economy strategy of the European Union. Two of them consisted of geopolymer panels incorporated into an External Thermal Insulation Composite System (ETICS) and a ventilated façade. This study evaluates their thermal performance by means of monitoring data from three pilot case studies in Greece, Italy, and Romania, and calibrated building simulation models enabling the reliable prediction of energy savings in different climates and use scenarios. Results showed a reduction in energy demand for all demo buildings, with annual energy savings up to 25% after placing the novel insulation solutions. However, savings are highly dependent on weather conditions since the panels affect cooling and heating loads differently. Finally, a parametric assessment is performed to assess the impact of insulation thickness through an energy performance prediction and a cash flow analysis.

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Online Implementation of a Soft Actor-Critic Agent to Enhance Indoor Temperature Control and Energy Efficiency in Buildings

Energies ◽

10.3390/en14040997 ◽

2021 ◽

Vol 14 (4) ◽

pp. 997

Author(s):

Davide Coraci ◽

Silvio Brandi ◽

Marco Savino Piscitelli ◽

Alfonso Capozzoli

Keyword(s):

Energy Consumption ◽

Temperature Control ◽

Weather Conditions ◽

Heating System ◽

Building Envelope ◽

Indoor Temperature ◽

Model Free ◽

Occupancy Patterns ◽

Online Implementation ◽

Indoor Temperature Control

Recently, a growing interest has been observed in HVAC control systems based on Artificial Intelligence, to improve comfort conditions while avoiding unnecessary energy consumption. In this work, a model-free algorithm belonging to the Deep Reinforcement Learning (DRL) class, Soft Actor-Critic, was implemented to control the supply water temperature to radiant terminal units of a heating system serving an office building. The controller was trained online, and a preliminary sensitivity analysis on hyperparameters was performed to assess their influence on the agent performance. The DRL agent with the best performance was compared to a rule-based controller assumed as a baseline during a three-month heating season. The DRL controller outperformed the baseline after two weeks of deployment, with an overall performance improvement related to control of indoor temperature conditions. Moreover, the adaptability of the DRL agent was tested for various control scenarios, simulating changes of external weather conditions, indoor temperature setpoint, building envelope features and occupancy patterns. The agent dynamically deployed, despite a slight increase in energy consumption, led to an improvement of indoor temperature control, reducing the cumulative sum of temperature violations on average for all scenarios by 75% and 48% compared to the baseline and statically deployed agent respectively.

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Optimization of Restoration Paths of Power System after Blackout

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.347-350.1467 ◽

2013 ◽

Vol 347-350 ◽

pp. 1467-1472

Author(s):

Wen Wei Huang ◽

Gang Yao ◽

Xiao Yan Qiu ◽

Nian Liu ◽

Guang Tang Chen

Keyword(s):

Power System ◽

Transmission Lines ◽

Reactive Power ◽

Minimum Spanning Tree ◽

Operation Time ◽

Combinatorial Problem ◽

Weather Conditions ◽

Recovery Process ◽

Point Of View ◽

Improved Genetic Algorithm

Optimization of restoration paths of power system after blackout is a multi-stage, multi-target, multi-variable combinatorial problem in the power system restoration. This paper presents a reasonable model and effectually method. The proposed model is considered as a typical partial minimum spanning tree problem from the mathematical point of view which considering all kinds of constraints. Improved data envelopment analysis (DEA) was used to get the weight which considering line charging reactive power, weather conditions, operation time and betweenness of transmission lines. The improved genetic algorithm method is employed to solve this problem. Finally, an example is given which proves the strategy of the line restoration can effectively handle the uncertainty of the system recovery process, to guarantee the system successfully restored after the catastrophic accidents.

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Multi-Objective Techno-Economic Optimization of Design Parameters for Residential Buildings in Different Climate Zones

Sustainability ◽

10.3390/su14010065 ◽

2021 ◽

Vol 14 (1) ◽

pp. 65

Author(s):

Muhammad Usman ◽

Georg Frey

Keyword(s):

Thermal Load ◽

Energy Demand ◽

Residential Buildings ◽

Optimal Solution ◽

Building Envelope ◽

Design Parameters ◽

Base Case ◽

Economic Optimization ◽

Single Family ◽

Climate Zones

The comprehensive approach for a building envelope design involves building performance simulations, which are time-consuming and require knowledge of complicated processes. In addition, climate variation makes the selection of these parameters more complex. The paper aims to establish guidelines for determining a single-family household’s unique optimal passive design in various climate zones worldwide. For this purpose, a bi-objective optimization is performed for twenty-four locations in twenty climates by coupling TRNSYS and a non-dominated sorting genetic algorithm (NSGA-III) using the Python program. The optimization process generates Pareto fronts of thermal load and investment cost to identify the optimum design options for the insulation level of the envelope, window aperture for passive cooling, window-to-wall ratio (WWR), shading fraction, radiation-based shading control, and building orientation. The goal is to find a feasible trade-off between thermal energy demand and the cost of thermal insulation. This is achieved using multi-criteria decision making (MCDM) through criteria importance using intercriteria correlation (CRITIC) and the technique for order preference by similarity to ideal solution (TOPSIS). The results demonstrate that an optimal envelope design remarkably improves the thermal load compared to the base case of previous envelope design practices. However, the weather conditions strongly influence the design parameters. The research findings set a benchmark for energy-efficient household envelopes in the investigated climates. The optimal solution sets also provide a criterion for selecting the ranges of envelope design parameters according to the space heating and cooling demands of the climate zone.

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