DHW tank sizing considering dynamic energy prices

Due to the rapid development of the building stock in Norway, the energy use in this segment is drastically increasing. Therefore, improving the energy performance of buildings becoming an urgent problem. Among technical systems in buildings, domestic hot water (DHW) systems have still significant untapped potential for energy saving. Storage tanks enable us to change DHW demand in buildings in a more energy-efficient and cost-effective way. However, to achieve this effect, the proper sizing and operation of the storage tanks are required. The aim of this study was to define a method for the DHW tank size optimization considering dynamic electricity prices and to assess how different electricity pricing methods would influence the DHW tank size. A dynamic discretized model of the DHW tank was used as a DHW tank model. Dynamic optimization was implemented as the optimization method to find the optimal tank charging rate based on the different pricing methods. Two pricing methods were considered in this study: 1) the current method with the fixed grid fee and 2) the power extraction method with the pricing of the maximum power extraction. The results showed that the electricity pricing pattern had significant impact on the DHW charging heating rate. In the case of the extraction fee pricing method, the charging rate was more stable over the day than in the case of the fixed grid fee. This stable charging rate gave stable DHW tank temperature over the day and the highest decrease in the total cost. A general conclusion was that the extraction grid fee pricing method would promote for stable charging over the day.

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Building Design Influence On The Energy Performance

Journal of Applied Engineering Sciences ◽

10.1515/jaes-2015-0005 ◽

2015 ◽

Vol 5 (1) ◽

pp. 37-46

Author(s):

Ligia Moga ◽

I. Moga

Keyword(s):

Residential Building ◽

Building Design ◽

Energy Performance ◽

Point Of View ◽

Hot Water ◽

Efficient Design ◽

Building Stock ◽

Existing Building ◽

Climatic Regions ◽

Energy Consumptions

Abstract Energy efficient design is a high priority in the national energy strategy of European countries considering the latest requirements of the European Directive on the Energy Performance of Buildings. The residential sector is responsible for a significant quantity of energy consumptions from the total amount of consumptions on a worldwide level. In residential building most of the energy consumptions are given mainly by heating, domestic hot water and lighting. Retrofitting the existing building stock offers great opportunities for reducing global energy consumptions and greenhouse gas emissions. The first part of the paper will address the need of thermal and energy retrofit of existing buildings. The second part will provide an overview on how various variables can influence the energy performance of a building that is placed in all four climatic zones from Romania. The paper is useful for specialist and designers from the construction field in understanding that buildings behave differently from the energy point of view in different climatic regions, even if the building characteristic remain the same.

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Baselines for Energy Use and Carbon Emission Intensities in Hellenic Nonresidential Buildings

Energies ◽

10.3390/en13082100 ◽

2020 ◽

Vol 13 (8) ◽

pp. 2100 ◽

Cited By ~ 2

Author(s):

Kalliopi G. Droutsa ◽

Constantinos A. Balaras ◽

Spyridon Lykoudis ◽

Simon Kontoyiannidis ◽

Elena G. Dascalaki ◽

...

Keyword(s):

Energy Use ◽

Average Energy ◽

Energy Performance ◽

Primary Energy ◽

Hot Water ◽

Building Stock ◽

Domestic Hot Water ◽

Energy Consuming ◽

Energy Use Intensity ◽

Cram Schools

This work exploits data from 30,000 energy performance certificates of whole nonresidential (NR) buildings in Greece. The available information is analyzed for 30 different NR building uses (e.g., hotels, schools, sports facilities, hospitals, retails, offices) and four main services (space heating, space cooling, domestic hot water and lighting). Data are screened in order to exclude outliers and checked for consistency with the Hellenic NR building stock. The average energy use and CO2 emission intensities for all building uses are calculated, as well as the respective energy ratings in order to gain a better understanding of the NR sector. Finally, in an attempt to determine whether these values are representative for the various Hellenic NR building uses, their temporal evolution is investigated. The average primary energy use intensity is 448.0 kWh/m2 for all NR buildings, while the CO2 emissions reach 147.5 kgCO2/m2. The derived energy baselines reveal that indoor sports halls/swimming pools have the highest energy use, while private cram schools/conservatories have the lowest, due to their operational patterns. Generally, from the four services taken into account, lighting is the most energy consuming, followed by cooling, heating and finally domestic hot water. For a total of 11 building uses, more data from the certificates will be necessary for deriving representative baselines, but, when it comes to buildings categories, more data are required.

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Linking Energy Poverty with Thermal Building Regulations and Energy Efficiency Policies in Portugal

Energies ◽

10.3390/en15010329 ◽

2022 ◽

Vol 15 (1) ◽

pp. 329

Author(s):

Ana Mafalda Matos ◽

João M. P. Q. Delgado ◽

Ana Sofia Guimarães

Keyword(s):

Energy Efficiency ◽

Winter Season ◽

Clean Energy ◽

Energy Performance ◽

High Energy ◽

Energy Prices ◽

Building Stock ◽

Energy Poverty ◽

Building Regulations ◽

Energy Efficiency Policies

Energy-poverty (EP) must be considered an energy-related issue since buildings are a central part of people’s daily lives. Thus, it has an important role in energy-related policy implementation. Even though the European Union (EU) has endorsed general energy efficiency through the Energy Efficiency Directive and Energy Performance of Buildings Directive recast, it was the Clean Energy Package for all Europeans that clearly highlighted EP. The growing concerns with EP have also been emphasised in subsequent directives and initiatives. Despite some regulatory framework and the milder climate situation, the proportion of the population experiencing thermal discomfort in southern and eastern European countries, namely in the winter season, is relatively high, reflecting the poor thermal performance of building stock, low family incomes and high energy prices, among others. The current work analysed the EP evolution in Portugal in the EU context, and the Thermal Building Regulations and Energy Efficiency Policies developed, aiming to add insight into the effectiveness of those policies concerning EP mitigation in Portugal as an EU Member state. Moreover, a critical debate on the potential to lower the EP Portuguese situation was also an objective to pursue. It is plausible to admit that reducing EP by acting on residential building stock, namely through the increase of energy efficiency and comfort, plays a key role in improving the living conditions, namely of vulnerable households and deprived areas. This will also decrease energy consumption and dependence while further promoting a smarter, sustainable and inclusive society, contributing to economic growth.

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Experimental Data and Simulations of Performance and Thermal Comfort in a Typical Mediterranean House

Energies ◽

10.3390/en14113311 ◽

2021 ◽

Vol 14 (11) ◽

pp. 3311

Author(s):

Víctor Pérez-Andreu ◽

Carolina Aparicio-Fernández ◽

José-Luis Vivancos ◽

Javier Cárcel-Carrasco

Keyword(s):

Energy Efficiency ◽

Thermal Comfort ◽

Energy Demand ◽

Natural Ventilation ◽

Thermal Characterization ◽

Energy Performance ◽

Building Stock ◽

Energy Demands ◽

Dwelling House ◽

Account Standard

The number of buildings renovated following the introduction of European energy-efficiency policy represents a small number of buildings in Spain. So, the main Spanish building stock needs an urgent energy renovation. Using passive strategies is essential, and thermal characterization and predictive tests of the energy-efficiency improvements achieving acceptable levels of comfort for their users are urgently necessary. This study analyzes the energy performance and thermal comfort of the users in a typical Mediterranean dwelling house. A transient simulation has been used to acquire the scope of Spanish standards for its energy rehabilitation, taking into account standard comfort conditions. The work is based on thermal monitoring of the building and a numerical validated model developed in TRNSYS. Energy demands for different models have been calculated considering different passive constructive measures combined with real wind site conditions and the behavior of users related to natural ventilation. This methodology has given us the necessary information to decide the best solution in relation to energy demand and facility of implementation. The thermal comfort for different models is not directly related to energy demand and has allowed checking when and where the measures need to be done.

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How Can Scientific Literature Support Decision-Making in the Renovation of Historic Buildings? An Evidence-Based Approach for Improving the Performance of Walls

Sustainability ◽

10.3390/su13042266 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2266

Author(s):

Valentina Marincioni ◽

Virginia Gori ◽

Ernst Jan de Place Hansen ◽

Daniel Herrera-Avellanosa ◽

Sara Mauri ◽

...

Keyword(s):

Energy Performance ◽

Decision Makers ◽

Cultural Value ◽

Correct Selection ◽

Evidence Based ◽

Historic Buildings ◽

Indoor Environmental Quality ◽

Building Stock ◽

Advantages And Disadvantages ◽

Assessment Design

Buildings of heritage significance due to their historical, architectural, or cultural value, here called historic buildings, constitute a large proportion of the building stock in many countries around the world. Improving the performance of such buildings is necessary to lower the carbon emissions of the stock, which generates around 40% of the overall emissions worldwide. In historic buildings, it is estimated that heat loss through external walls contributes significantly to the overall energy consumption, and is associated with poor thermal comfort and indoor air quality. Measures to improve the performance of walls of historic buildings require a balance between energy performance, indoor environmental quality, heritage significance, and technical compatibility. Appropriate wall measures are available, but the correct selection and implementation require an integrated process throughout assessment (planning), design, construction, and use. Despite the available knowledge, decision-makers often have limited access to robust information on tested retrofit measures, hindering the implementation of deep renovation. This paper provides an evidence-based approach on the steps required during assessment, design, and construction, and after retrofitting through a literature review. Moreover, it provides a review of possible measures for wall retrofit within the deep renovation of historic buildings, including their advantages and disadvantages and the required considerations based on context.

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Optimal Renovation Strategies through Life-Cycle Analysis in a Pilot Building Located in a Mild Mediterranean Climate

Applied Sciences ◽

10.3390/app11041423 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1423

Author(s):

José Manuel Salmerón Lissen ◽

Cristina Isabel Jareño Escudero ◽

Francisco José Sánchez de la Flor ◽

Miriam Navarro Escudero ◽

Theoni Karlessi ◽

...

Keyword(s):

Life Cycle ◽

Life Cycle Cost ◽

Mediterranean Climate ◽

Building Envelope ◽

Economic Life ◽

Hot Water ◽

Optimal Solutions ◽

Building Stock ◽

Existing Building ◽

The Cost

The 2030 climate and energy framework includes EU-wide targets and policy objectives for the period 2021–2030 of (1) at least 55% cuts in greenhouse gas emissions (from 1990 levels); (2) at least 32% share for renewable energy; and (3) at least 32.5% improvement in energy efficiency. In this context, the methodology of the cost-optimal level from the life-cycle cost approach has been applied to calculate the cost of renovating the existing building stock in Europe. The aim of this research is to analyze a pilot building using the cost-optimal methodology to determine the renovation measures that lead to the lowest life-cycle cost during the estimated economic life of the building. The case under study is an apartment building located in a mild Mediterranean climate (Castellon, SP). A package of 12 optimal solutions has been obtained to show the importance of the choice of the elements and systems for renovating building envelopes and how energy and economic aspects influence this choice. Simulations have shown that these packages of optimal solutions (different configurations for the building envelope, thermal bridges, airtightness and ventilation, and domestic hot water production systems) can provide savings in the primary energy consumption of up to 60%.

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RINNO: Towards an Open Renovation Platform for Integrated Design and Delivery of Deep Renovation Projects

Sustainability ◽

10.3390/su13116018 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6018

Author(s):

Theo Lynn ◽

Pierangelo Rosati ◽

Antonia Egli ◽

Stelios Krinidis ◽

Komninos Angelakoglou ◽

...

Keyword(s):

Value Chain ◽

Residential Buildings ◽

Integrated Design ◽

Energy Performance ◽

Building Stock ◽

Existing Building ◽

Horizon 2020 ◽

Regulatory Standards ◽

Automation Systems ◽

Wide Range

The building stock accounts for a significant portion of worldwide energy consumption and greenhouse gas emissions. While the majority of the existing building stock has poor energy performance, deep renovation efforts are stymied by a wide range of human, technological, organisational and external environment factors across the value chain. A key challenge is integrating appropriate human resources, materials, fabrication, information and automation systems and knowledge management in a proper manner to achieve the required outcomes and meet the relevant regulatory standards, while satisfying a wide range of stakeholders with differing, often conflicting, motivations. RINNO is a Horizon 2020 project that aims to deliver a set of processes that, when working together, provide a system, repository, marketplace and enabling workflow process for managing deep renovation projects from inception to implementation. This paper presents a roadmap for an open renovation platform for managing and delivering deep renovation projects for residential buildings based on seven design principles. We illustrate a preliminary stepwise framework for applying the platform across the full-lifecycle of a deep renovation project. Based on this work, RINNO will develop a new open renovation software platform that will be implemented and evaluated at four pilot sites with varying construction, regulatory, market and climate contexts.

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