Non-residential Building Sector Research Articles

A Review of Non-Residential Building Renovation and Improvement of Energy Efficiency: Office Buildings in Finland, Sweden, Norway, Denmark, and Germany

Existing buildings are a source of great potential for energy efficiency through renovation. In this study, the national energy requirements equivalent for the major renovation of existing non-residential buildings using the example of office buildings in five European case countries are drawn out and discussed. The non-residential building sector has been found to be complex and heterogenous with much less available data than for the residential sector, but having greater average specific energy consumption per floor area. The existing non-residential building stock in the studied countries has been divided into varying amounts of groups and sub-groups. The energy requirements have been shifting from the increasing requirements for the U-values of the building envelope (before the 2000s) towards calculated energy demand for buildings as a whole (currently). The requirements for buildings in the near future will be carbon emission based. The energy efficiency of N-RBs in all of the studied case countries have been steadily improved during different decades of construction. Relatively older office stock combined with the relatively late introduction of national energy requirements was found to have a significantly larger potential for energy savings. Different terms and contents in national requirements were used to describe the principles of “major renovation” as from EPBD.

Energy and thermal analysis of DSF in the retrofit design of office buildings in hot climates

ABSTRACT In recent decades, the energy retrofit design of buildings has been one of the most effective methods to achieve high-performance buildings. The government office buildings in Iran account for 15% of the non-residential building sector; hence, energy retrofitting of existing office buildings could effectively reduce total energy consumption and Carbon dioxide emissions. This study aims to evaluate the effect of various facade systems with cool materials on the thermal behavior and energy performance of a typical existing office building in a hot climate. The proposed hybrid retrofit method combines design and energy retrofit strategies while evaluating the effects of different workspace layouts and facade systems on external surface temperatures and total energy consumption. Applying such a method, the most optimal design and energy retrofit strategies were selected using a combination of optimization and scenario-based approaches. The results showed that using double-skin facades could reduce annual energy consumption and Carbon dioxide emissions by 63%. Moreover, the results indicated the most efficient types of cool coatings materials for reducing cooling loads.

Assessment of the energy consumption in non-residential building sector in Brazil

This paper provides a pioneering, top-down analysis of the non-residential building stock in Brazil. A country-wide dataset was used, comprising 10,000 buildings divided into 12 typologies. Key indicators include floor area, energy use intensity, and operation patterns. In addition, predominant wall constructions, lighting systems, equipment, water heating, and HVAC systems for each typology were identified, including average density power for the systems. Data from the Brazilian Energy Balance report was correlated with the sample of buildings to determine the proportion of each building typology in the total energy consumption of the country, considering different energy sources. This study provides an innovative and up-to-date status of the characteristics of non-residential buildings in Brazil. A complementary statistical analysis addressed the correlation between energy use intensity and the building characteristics including an ANOVA test and a regression analysis in order to investigate the influence of the energy usage indicators (Lighting Power Density, Equipment Power Density, Cooling capacity) on the energy use intensity of each building typology in Brazil. This study is intended to serve as a reference for building characteristics and building energy performance in Brazil, and hence support diverse research regarding country-level building stock modeling, energy benchmarking, climate change impacts, and energy-efficiency related studies.

Techno-economic evaluation of building envelope solutions in hot arid climate: A case study of educational building

Building energy use is becoming increasingly important worldwide, with the increasing necessity to attain indoor thermal conditions. The high temperatures in hot climates cause human dissatisfaction resulting in higher use of air conditioning systems. As a result, energy in those buildings rises regularly driven by the increase in the air conditioning systems operation. In the non-residential building sector, the air conditioning system consumes the majority of the building’s energy to satisfy the thermal comfort requirements. With this aim, simulations have nowadays become an important tool to fulfill various high-performance buildings. Dynamic simulations have often been used by designers to evaluate buildings’ energy performance to accomplish specific goals, as minimizing energy usage and environmental impacts. This study analyzes the energy savings obtained by the execution of retrofitting measures in an educational building located in Egypt through dynamic simulations of the building performance. The main objective is the creation of a decision matrix to select an optimal solution for the building envelope based on the effectiveness of thermal insulation, cost, and environmental factors. Based on the precise physical characteristics of the building’s vacancy schedule, geographical location, weather conditions, and the nature of construction, overall energy consumption would be determined. A sensitivity analysis is undertaken to assess the key factors that influence building energy consumption through the validated baseline model. The envelope is chosen as it is vital for the building’s energy efficiency and could account for up to 50% of the total heat gain in a building. Thermal insulation is one of the most effective implementations to provide desirable thermal comfort and minimize heat transfer into buildings, resulting in an energy consumption reduction. Two insulation materials are assessed through the building simulation model, the cost of each measure is estimated, and the emissions mitigation produced is obtained. With this information, a decision matrix is created that allows highlighting the best option based on the effectiveness of the measure in Egyptian hot arid climates. Among different insulations surveyed in Egypt, the study highlighted the effectiveness of using Extruded polystyrene insulation (XPS) with a thickness of 25 mm, resulting in reductions of about 16% in Heating, Ventilation, and Air-Conditioning (HVAC) energy consumption and 8% of the overall energy consumption with a payback period of about 25 months and a 29% Return on investment (ROI).

NZEB and market-based renovation case study of an existing office building

The goal of decarbonizing the building stock in the EU requires a multi-fold increase of the current renovation rates. In Estonia, the non-residential building sector has had little or no public support to improve the energy efficiency. Therefore, it is essential to study the energy efficient and cost-optimal measures for non-residential building renovation to give guidance to real estate companies and other stakeholders about the renovation alternatives. Furthermore, crucial is to provide input to the government to develop the renovation grant and incentives for renovation. In this study, energy renovation measures and savings to improve the energy performance to NZEB level were identified in a large (16 990 m2heated area) office building. For that purpose, energy use was measured, simulation model developed and calibrated, feasible and more comprehensive energy improvements and costs analysed. The improvement of lighting, AHU, heating, installation of a 69 kW PV system, and window replacement was needed to achieve the goal with a primary energy use of 163 kWh/m2. However, some of the applied measures had long payback times of 40-70 years and are not realistic to be implemented without renovation incentives.

Analysis of the embodied carbon dioxide in the building sector: A case of China

Many studies and standards in the building sector have often focused on the mitigation of operational carbon with little consideration of the embodied carbon from buildings. Although there exist some studies on embodied carbon, they are analyzed based on the project level or case studies, and few studies explore the embodied carbon dioxide in the building sector. To achieve the peaking of China’s carbon emission by 2030, a process-based approach and a disaggregated input-output model in this study were adopted to estimate the annual embodied carbon dioxide from the China’s building sector, respectively. The results of embodied carbon dioxide emissions were 1421.70 Mt and 1599.62 Mt in the building sector in 2015, respectively. In terms of building types, the embodied carbon dioxide in the residential building sector is about 1.5–2.2 times that of the non-residential building sector. In addition, it is indicated that, unlike the small magnitude of embodied carbon compared with operational carbon in life cycle of buildings, the annual embodied carbon dioxide accounts for roughly one-half in the total carbon dioxide emissions in the building sector in 2015. The study provides an understanding of the embodied carbon and its composition of different industrial materials that would be useful for China to develop its future CO2 emission control plan.

Life Cycle Energy Assessment of a School Building under Envelope Retrofit: An Approach towards Environmental Impact Reduction

Energy efficiency of existing buildings is a concept to manage and restrain the growth in energy consumption and one of the crucial issues due to the magnitude of the sector. Educational buildings are in charge of about 15% of the total energy consumption of the non-residential building sector. However, not only operational but also embodied energy of a building should be reduced to get the overall benefits of energy efficiency, where, using energy efficient architectural measures and low emitting materials during every retrofit action can be a logical step. The majority of buildings in Turkey and EU was built earlier than the development of the energy efficiency in the construction sector, hence, without energy retrofit, consume an enormous amount of energy that can be averted significantly by the implementation of some even not advanced retrofit measures. Furthermore, demolishing of a building to construct a new one is not a rational approach concerning cost, time and environmental pollution. The study has been focused on the impact assessment of the various architectural scenarios of energy efficiency upgrading on the Life Cycle Energy Consumption (LCEC) and Life Cycle CO2 (LCCO2) emission. Within the scope of the study, a primary school building is selected to be analysed. Through analysis, the total embodied and operational energy use and CO2 emission regarding the life cycle phase of the building is quantitatively defined and investigated in the framework of life cycle inventory. The paper concentrates on the operation and embodied energy consumption arising from the application of a variety of measures on the building envelope. An educational building with low LCCO2 emissions and LCEC in Turkey is proposed. To exemplify the approach, contributions are applied to a case study in Istanbul as a representative school building. The primary energy consumption of the case study building is calculated with a dynamic simulation tool, EnergyPlus. Afterwards, a sort of architectural energy efficient measures is implemented in the envelope while the lighting and mechanical systems remain constant. The energy used in the production and transportation of materials, which are the significant parts of the embodied energy, are taken into account as well.

German Energiewende—different visions for a (nearly) climate neutral building sector in 2050

In order to contribute to the German Energiewende (energy transition) adequately, the building sector has to be almost completely decarbonised in the long term. Our analysis investigates how the German building stock can be transformed into a nearly climate-neutral state by 2050. Using a stock modelling approach based on a typology of the German residential and non-residential building sector, we develop different visions (target states) of what a nearly climate-neutral building stock could look like. All developed target states achieve the overall goal of reducing the non-renewable primary energy demand in 2050 by at least 80%. In order to span a broad target corridor, the target states differ in the two central target dimensions: efficiency (reduction in final energy demand) and energy/technology supply mix (especially the herein contained share of renewable energies). Additionally, using the energy system model REMod-D, the interactions of the building stock with the energy system as a whole are investigated. We explore the differences between a target state focussing on efficiency measures and a target state where efficiency is partly compensated for by an increased use of renewable energies. We learn that from a private cost perspective no clear recommendation can be derived as to which target state should be given priority. This means that other criteria become more relevant, such as social acceptance regarding the different measures, or the challenges that arise from rolling out additional renewable energy capacity on top of what is necessary to achieve the climate goals in other sectors.

Improving sustainable office building operation by using historical data and linear models to predict energy usage

Offices and retail outlets represent the most intensive energy consumers in the non-residential building sector and have been estimated to account for more than 50% of a building’s energy usage. Accurate predictions of office building energy usage can provide potential energy savings and significantly enhance the efficient energy management of office buildings. This paper proposes a method that applies multiple linear regression (MLR) and artificial neural network (ANN) models to predict energy consumption based on weather conditions and occupancy; thus, enabling a comparison of the use of these two types of modelling methods. In this study, four models of office sites at research institutions in different New Zealand regions were developed to investigate the ability of simple models to reduce margins of error in energy auditing projects. The models were developed based on the monthly average outside temperature and the number of full-time employees (FTEs). A comparison of the actual and predicted energy usage revealed that the models can predict energy usage within an acceptable error range. The results also demonstrated that each building should be investigated as an individual unit.

A review on Latvian Historical Building Stock with Heavy Walls

The conservation of historic buildings’ cultural values and the improvement of their energy performance can be perceived as rather contradictory. A thermal insulation cannot always be applied on the exterior surface of external walls. In that case, interior insulation measures should be investigated and currently represent the most difficult retrofit measure in historic buildings. The main objective of this study is to carry out literature review and to examine most commonly found historic building heavy wall types in Latvia, determine their physical properties, classify them by different types, observe and describe main historic building envelope deterioration symptoms and their possible causes. The study shows that historical buildings consume one third of total final heating energy consumed by both residential and non-residential building sector. The study also reveals that historical building external wall hygrothermal properties have not been widely studied in Latvia. This study will serve as basis for development of effective, comprehensive decision guidelines to improve the energy performance of historic buildings by investigating interior insulation measures.

Material stocks of the non-residential building sector: the case of the Rhine-Main area

The building sector is known to have the largest inventories of materials in industrialized societies. In comparison to residential buildings, non-residential buildings (NRBs) are much more diverse in function, components and their respective materials. In order to provide insights in material stocks of the non-residential area, this study focused on the case of the Rhine-Main area, a metropolitan region holding extensive stocks of office buildings as well as factory, logistic and other NRBs. The investigation covered analysis of spatial data and examination of single buildings. The structure of the NRB sector was comprehensively characterized in a case-study area as to function and age-classes of existing buildings in terms of building gross volume. The two types “factory” and “commercial/retail and services buildings” accounted for about half of the existing buildings. As to age, about one third of the buildings was found to originate before 1948. This indicates the high importance of renovation activities as a prerequisite for the continuous use of NRBs. Specific material contents of buildings were assessed, showing a large variety. Combining spatial and building related information, a methodological approach was developed which provides area-wide information on material stocks incorporating the allocation to function and age-class of NRBs. This approach may be used for regional estimation of potentials of secondary resources and for Material Flow Analysis in order to estimate potentials and flows of secondary resource.

Prospects for Appearance Wood Products Ecodesign in the Context of Nonresidential Applications

Abstract As environmental awareness grows, societal demand for more environmentally friendly products increases. Demand for environmental responsibility also reached the building material and construction sector. Green building has become more widespread over the past decade and can be considered a challenge for specifiers and building products manufacturers. Ecodesign, an application of the sustainable development concept, is one of the available tools to address this challenge. This article aims at proposing an ecodesign pathway for appearance wood products in the nonresidential building sector. Through extrapolating results from a previous interior wood door case study, it has been possible to obtain environmental profiles for the main segments of the appearance wood products family for nonresidential buildings. These profiles have allowed devising ecodesign solutions. Results show that for this whole family of products, raw materials are what cause the most environmental impacts, followed by shipping ...

Designing a whole-life building cost index in Singapore

Purpose – The purpose of this paper is to investigate the whole-life costs of non-residential green-rated building developments in Singapore to derive useful information for research and practice. When industry stakeholders like building owners, architects, engineers, quantity surveyors, builders and facility managers have detailed information about the initial and operating costs of different types of buildings, they will be able to apply whole-life costing to their existing or new projects with the intention of achieving value for money, as well as environmental sustainability. The developed index is useful to green policymakers and building owners. Design/methodology/approach – Data are collected from building projects certified by the Building and Construction Authority (BCA) of Singapore under the Green Mark scheme, starting from 2005. Statistical analysis is performed on the collected data to generate the information required to build the index as well as cost database. The Paasche price index method is used to produce a weighted composite index for Singapore’s non-residential building sector. Findings – The results show the classification of whole-life costs components by two main groups – “development and construction costs”, and “operating and maintenance costs”. There are a total of 68 cost significant items selected from 13 construction work categories. Comparing the weights for three non-residential building types, the highest is obtained for industrial building, which is followed by institutional and commercial buildings. Research limitations/implications – Without data, the description of the research has primarily dealt with the formulation of the proposed index because designing an appropriate methodology is key to ensure widespread acceptance and use. Practical implications – Prospective users have to be aware that the index cannot provide information about change in absolute terms and is not very accurate as such in reflecting the actual level of costs or prices of the variable of interest. However, it is a good indicator of the relative change over time in the level of costs or prices. Originality/value – It is expected that this method contributes additional information to BCA’s existing tender price index about a building’s operating costs as well since the proposed index is a measure of change in the average whole life-cycle costs of buildings over time.

Using life cycle thinking to analyze environmental labeling: the case of appearance wood products

Growing public concern about the current state of our planet led to the creation of numerous regulations, standards, and certifications for the protection of humans and the environment. Ecolabels were defined for products such as cleaning products, paints, and many others. Wood building products are no exception. The objective of this study is to analyze the existing ecolabelling programs for appearance wood products in nonresidential applications and to evaluate them relatively to their effective role in environment protection or reduction of environment footprint. The research was conducted on the most common International Organization for Standardization (ISO) type I ecolabels in North America, the European Union, and Japan. Certification schemes applicable to appearance wood products for nonresidential applications were considered. In a life cycle assessment perspective, certification criteria were compared regarding their ability to consider and integrate environment impacts. A wide range of ecolabels can apply to appearance wood products, from indoor air quality to wood from sustainable forest management. Moreover, it has been found that among all certification schemes studied, those integrating the whole life cycle were the most relevant. The remaining limitation of ISO type I ecolabels is the lack of environmental information enabling the differentiation between products bearing the same ecolabel. This can be overcome by ISO type III environmental product declarations. Thus, allowing a better understanding of the implications related with the use of wood products compared to other materials in the nonresidential building sector.

Energy and exergy analysis of the Greek hotel sector: An application

Energy consumption in buildings vary significantly, depending on factors as the use of the building, the construction type, maintenance, existing heating, cooling and lighting systems and other types of services. Hotel buildings have high energy consumption rate, as a result of their unique operational characteristics. Energy consumption in hotels is among the highest in the non-residential building sector in absolute values. Available specific information on the energy characteristics, thermal performance, energy losses, electric loads, and comfort conditions play significant role for the sustainable development of hotel's systems. These data can also be used to identify whether there is space for improvement in new or existing hotels by comparing them against predicted or actual building energy performance. The aim of the present paper is to analyze the energy and exergy utilization in four hotels in Rethimno, Crete (Southern Greece) and in Kassandra, Halkidiki (Northern Greece).