Building Energy Performance Assessment Research Articles

On the Establishment of Climatic Zones in Europe with Regard to the Energy Performance of Buildings

Nowadays, subjects such as eco-design requirements, product rating or code compliance with regard to energy efficiency are expanding towards a pan-European level. This leads to the necessity of defining zones within the European region, which share common climatic characteristics and will further facilitate the quick estimation of building energy performance. Towards this direction stands the current paper; it presents an approach for defining climatic zones in Europe on the basis of the amount of heating and cooling degree days. It is applied for the climate classification of selected European cities and is compared with the conventional scheme based solely on heating degree days. Since the approach is orientated mainly towards the assessment of building energy performance, its outcomes are evaluated with regard to the actual heating and cooling energy needs of a reference building unit with office use located in representative cities of the proposed climatic zones and facing the four cardinal orientations. The classification of climatic zones on the basis of both heating and cooling degree days leads to more realistic results, since nowadays cooling needs form a substantial part of the energy balance of the building, especially in the Mediterranean regions.

Using indicators to profile energy consumption and to inform energy policy in a university—A case study in Ireland

The services sector has the least amount of energy end use data available, which poses significant challenges to companies within the sector attempting to benchmark their energy performance and inform energy management decisions. This paper explores through a case study analysis the use of simple performance indicators and how additional data and new metrics can greatly enhance the understanding of energy trends and in particular the assessment of building energy performance. The country chosen for the analysis is Ireland, where the services sector has experienced high energy demand growth since 1990 (4.1% annually) compared with the EU-15 (1.5% annually). Despite this growth, the available energy data is poor, in particular for the public service sub-sectors. The case study chosen is an institution within the education sub-sector, University College Cork. The paper presents some simple energy performance indicators that have been used to date to inform energy policy. The paper then introduces new approaches and tools for assessing energy performance in buildings and how these may be utilised to improve the energy policy decision making and energy management. It discusses how these approaches are been implemented for buildings with separate functions, presents some initial results and discusses future planned work.

Comparison of user performance when applying system identification for assessment of the energy performance of building components

The application of system identification techniques to the energy performance assessment of buildings and building components requires a high level of knowledge of physical and mathematical processes. This factor, combined with the quality of the data, the description of the monitoring procedure and test environment, together with the experience of the user of the analysis software itself, can produce varying results from different users when applying different models and software packages. Past international system identification competitions (1994 and 1996) demonstrated the spread in results that can be expected regarding the application of different models and techniques to the same benchmark data. The PASLINK EEIG has attempted to consolidate and strengthen knowledge and expertise of system identification techniques within the grouping and also ensure that data analysis meets minimum quality levels. This paper compares the spread in results obtained during the previous competitions to that obtained during the workshops carried out by the PASLINK EEIG following 10 years of networking activities in the field. The objective is to identify the extent to which the networking activities have strengthened the position of the individual teams working in the field and to identify the areas where quality assurance is met and, furthermore, where further improvements can be made. A direct comparison of the quality of results obtained during data analysis from the previous decade is made with recent results after a significant period of collaboration and networking activities.

Performance assessment of low-energy buildings in central Argentina

This paper summarizes the results obtained from the energy and thermal performance assessment of residential and non-residential low-energy buildings that were designed to minimize fossil energy use. They are located in the province of La Pampa, central Argentina, in a temperate continental climate that shows extreme hot and cold records during the summer and winter seasons, respectively. The common applied technologies for saving energy were passive solar heating, natural ventilation for cooling and daylighting. The glazing area in the principal functional spaces facing to the North oscillates between 11 and 17% of the building useful areas. All the studied buildings are massive, with the exception of an auditorium that was designed with a lightweight insulated technology. The mean thermal transmittance of the envelope is 0.45 W/(m 2 K). Double glazing and hermetic carpentry were used to reduce thermal losses ( U-value = 2.8 W/(m 2 K)). The volumetric heat loss coefficient ( G-value) oscillates between 0.90 and 1.00 W/(m 3 K). During the design and thermal simulation convective-radiative heat transfer coefficients were estimated through a dimensional equation ( h = 5.7 + 3.8 ws, wind speed). On internal surfaces, convective-radiative heat transfer coefficients of 8 and 6 W/(m 2 °C) (for surfaces with and without solar gain, respectively) were applied. The monitoring process provided information on the energy and thermal behaviour under use and non-use conditions. The measured value of energy consumption was similar to the expected value that was used during the pre-design stage. Building technologies work well during the winter season, allowing 50–80% of energy savings. However, overheating is still an unresolved problem during the summer. Interviews with occupants revealed that they need both, information about functional details, and good-practice guidance to manage thermal issues of the building. In most cases, the annual consumption of energy was lower than those established by the Low Energy Housing German Standards and the Minirgie Switzerland Certificate. Despite their relative cost increase during the last years, the use of insulation technology and the application of passive solar devices involved an extra cost of only 3% in our works. Provided the expected depletion of natural gas production in the coming decade, the importance of applying energy-efficiency guidelines will increase very soon in Argentina in order to match the requirements of a new national energy matrix.

Assessing energy performance in the latest versions of Hong Kong Building Environmental Assessment Method (HK-BEAM)

The latest (4/04 and 5/04) versions of the Hong Kong Building Environmental Assessment Method (HK-BEAM), one covering new buildings and the other existing buildings, have been formally launched in 2005. The paper describes the building energy performance assessment method in these latest HK-BEAM versions. With the use of the energy budget approach, the assessment framework is applicable to a wide range of buildings that may comprise different mixes of premises types. The new scheme provides bonus credits for provisions that allow utilization of renewable energy sources. For existing buildings, it makes allowances for plant performance degradation and constraints to implementation of improvement measures in existing buildings. So far, the new assessment method has been applied to six building developments, including commercial complexes and residential developments. The assessment results are presented and discussed in the paper.

Establishment of energy management tools for facilities managers in the tropical region

PurposeTo establish national energy performance benchmarks and an energy efficiency classification system for commercial office buildings from whole building to sub‐systems level for building professionals including facility managers.Design/methodology/approachIssuing of survey form and questionnaires to 16 building owners before field interview. Building physical data and systems nameplate, quantities and types were verified on site. The past 24 months electricity consumption bills were also collected from building owners. Physical environmental conditions and short‐term power measurement on building systems were done to determine the level of energy consumption and performance.Research limitations/implicationsThe classification and benchmarking methodology developed is useful for the regions to establish their own database and tools.Practical implicationsThe building energy performance assessment and auditing methodology are useful to both building owner/manager and energy services companies (ESCOs) in carrying out systematic assessment and analysis on building energy characteristics. The benchmark system established will also serve as a reference to building professionals to adopt a more holistic approach in designing an energy efficient building. Useful also for building owners who are considering carrying out retrofitting works on their existing building or systems.Originality/valueThe study provides detailed whole building and systems benchmarks for Singapore. The results provide an objective evaluation system of commercial office building energy performance.

Building Energy Efficiency Assessments in Hong Kong and the Way Forward

The Hong Kong Government has issued five codes of practice on energy efficiency of buildings, including one on overall thermal transfer value (OTTV) of buildings and four on major services installations in buildings. Compilance with the OTTV code is now a legal requirement to new commercial and hotel buildings. Although the other four codes were also intended for mandatory implementation, they are being implemented under the voluntary Hong Kong Energy Efficiency Registration Scheme for Buildings (HKEERSB). The Hong Kong Building Environmental Assessment Method (HK-BEAM) is a private sector voluntary scheme, which assesses a wide range of environmental issues, including energy efficiency. The scope, methods and criteria of building energy performance assessment in the two schemes are largely different. Yet, the performance-based assessment method and the philosophy adopted for setting the zero credit levels in HK-BEAM make it a suitable alternative compliance route to the codes. The need for, and the benefits of having such an alternative route to prescriptive controls in the codes are discussed and exemplified through a comparison of the assessment results of a building that has undergone both the HKEERSB and the HK-BEAM assessments. The study revealed that the minimum performance level that would pass the lighting and air-conditioning codes would lead to zero credits under the HK-BEAM assessment, which is a reflection that buildings obtaining some credits would have an energy performance standard above the minimum set by the codes, and that it would be important to allow trade-offs amongst the assessed issues in the codes.