Energy Auditing of a Building using Green BIM

Transcription

1 Volume 1, Issue 1, July-September, 2013, pp , IASTER Online: , Print: Energy Auditing of a Building using Green BIM 1 Gokulavasan.M, 2 Ramesh Kannan.M 1 PG Student, Structural Engineering, VIT University, Chennai Campus, India, 2 Assistant Professor, Department of Civil Engineering, VIT University, Chennai, India, ABSTRACT The energy auditing for building is the most important step that can contribute to energy conservation. It is a significant activity in energy management strategy. Specific technical skills are required for efficient performance of an energy audit building. Building Information Modelling (BIM) is a computer based analytical process that helps to evaluate the energy performance of a building and make it more energy efficient by making necessary modifications in the design before the building is constructed. It offers powerful capability assess alternative energy strategies and system in the earliest phase of design. This paper includes a preliminary study for a typical G+1 residential building and calculation of its energy performance. The initial approach was to create the 2D plan for a residential building with the help of the AutoCAD 2013 and 3D modelling of that building using Revit 2013 and energy auditing was done. Keywords: Building Information Modelling, energy audit, energy efficiency, simulation, sustainability. I. INTRODUCTION The energy auditing in a building is feasibility study. Normally energy audit is an inspection survey and analysis of energy flows for energy conservation in a building process or system to reduce the amount of energy input in to the system without negatively affecting the output. Energy audit is not only service to identify energy use and it is also used to identify the opportunities for energy conservation. The audit will produce the data on which such a programme is based. The study will be revealed to the owner, client or management team of the building the option available for reducing the energy waste, the cost involved and the benefits achievable from implementing those energy conservation opportunities (ECOs). The energy management programme is a systematic ongoing strategy for controlling a building energy consumption pattern [1]. The development of energy auditing methodology based on energy efficient design (EED) principle was adapted in commercial buildings. Various auditing applications to existing buildings prioritizing the retrofitting opportunities is claimed to be energy saving.[2].four low rise residential college building were selected in finding the relationship between green/passive building strategies and energy performance. As initial finding the implementation of appropriate green building strategies is able to provide positive impact to the overall energy performance of the residential colleges [3]. Taiwan is located near the equator subtropical zone. The design scheme on light management system to reduce power consumption of the power system in a Taiwan research is done to the building by means of the utilization of natural daylight [4]. Energy auditing of shanghai commercial building mainly focus on the consumption of equipment, especial on air-conditioning system, lighting system and elevator. In winter season energy audit investigation field measurement of the indoor environment has been carried out [5]. The first step is to improve the energy efficiency of buildings by identifying opportunities to reduce energy 7

2 consumption. Energy audit result has been conducted during 2010 in a Portuguese school building technology, professional school and artistic school of Pombal [6]. Envelope thermal transfer value (ETTV) equation calculates the energy conservation of residential building and hence lowering the ETTV will result in reduced building heat load. Further development of ETTV equations provides unit reduction in annual cooling energy [7]. The renewable and sustainable energy sources are available. Renewable forms of energy are constantly replenishing themselves with little or no human effect. Firewood, water and solar energy is the example of the renewable form of energy. Sustainable forms of energy are not only renewable but they also have the ability to keep the earth s echo system up and running in perpetuity. Now a day s Building information modelling demand is rapidly growing one. It can obtain unprecedented insight in to how building will perform long before construction begins. It can help you design more efficiently, deliver higher quality and obtain earlier approvals, more sustainable with fewer complications during the process of construction. Ultimately this approach helps more consistent, predictable outcomes. Autodesk Revit helps you to model and analyse design concepts and more accurately maintain your vision through design, documentation and construction. Building as they are designed today contributes to serious environmental problem because of excessive consumption of energy. Energy resource efficiency for new construction can be affected by adopting an integrated approach to the building design. This primary step approaches are listed below: 1. Incorporate solar passive technique in a building design to minimise the load on conventional system. Passive system provides visual and thermal comfort by using natural energy source. 2. The solar passive systems vary from one climate to other. Energy flows in this system are by natural means such as radiation, conduction, and convection with minimal. 3. Use renewable energy system to meet a part of building load. 4. Design HVAC system and energy efficient lightening once the passive solar architectural concepts are applied to the design. In building requirements of electrical energy to rectify the use of solar energy reduce consumption of conventional form of energies. Various input data before configuring building 1. Geometry of the building 2. Orientation of the building 3. Building construction which includes the thermal properties of all the building elements including walls, roofs, windows, floors, ceiling, and doors. 4. Functional usage of the building 5. Weather data II. MODELLING AND ANALYSIS OF BUILDING The typical G+1 residential building is considered in Chennai zone, the total area of the building is 1565 square feet. Building is located in the Chennai zone at the latitude of 13 north and latitude of east 8

3 Figure. 1 G+1 Residential building plan The above Fig.1 represents the plan of the G+1 typical residential building by using AutoCAD software. Figure. 2 Model of G+1 residential building The residential building plan is implemented to the Revit software for modelling purpose. Fig.2 represents the 3D modelling of the typical G+1 residential building. III. METHODOLOGY 1. Conceptual Mass Design Using Building Information Modelling The concept design of a building including its element and space objects. Spaces are multi-storey spaces must be representing at distinct spaces at each level of the buildings. The site, building location, elevation and orientation are should be considered. 2. Adjust and Prepare BIM for Energy Analysis Specify the setting according to our requirements i.e. type of the building, location and various energy model parameters. Required changes in HVAC systems and other energy criteria. 3. Enable Energy Model Building design BIM was prepared for analysis by enabling the energy model. The model of the building is divided in two different spaces by the BIM cloud service. 9

4 4. Run Energy Simulation The model is ready for analysis which is connected to the cloud server from where each and every space is validated for energy simulation. IV. RESULTS AND DISCUSSION Energy demand is the Heating and cooling load that may be used for the purpose of Heat Ventilation Air Conditioning system sizing. Energy demand represents the maximum thermal load on the building for the specified design days for the winter and or cooling season. It will be calculated for each zone and the total demand is obtained by aggregating the zone peak loads for the specified design hour. It will be calculated based on the proposed building space layout, proposed construction types assigned to building elements, HVAC system, outside air requirements, internal loads from people, lighting and equipment, internal loads from people. Annual energy consumption is the energy used every year for heating, cooling, lighting and equipment the building. It may be determined for each space, zone, and or as a total consumption for the building. Energy simulation results for G+1 residential building at Chennai location from Autodesk Revit conceptual energy analysis data are following- 1. Building Performance Factors Table.1 Table represents the building performance factors S.No Criteria Description 1 Location Chennai,TamilNadu,India. 2 Outdoor Temperature Max:104 o F/Min:50 o F 3 Floor Area 1565 sf 4 Average Lighting power 0.45W/ft 2 5 People 3 people 6 Exterior window Ratio Electrical Cost $0.05/kWh 8 Fuel Cost $0.14/Therm 2. Energy Use Intensity Table.2 Table represents the energy use intensity S.No Criteria Description 1 Electricity EUI 19kWh/sf/yr 2 Fuel EUI 11kBTu/sf/yr 3 Total EUI 19kBTu/sf/yr 3. Life Cycle Energy Use/Cost Table.3 Table represents Life cycle energy use/cost S.No Criteria Description 1 Life Cycle Electricity Use 1,611,216 kwh 2 Life Cycle Fuel Use 9,324 Therms 3 Life Cycle Energy Cost $34,994 10

5 4. Renewable Energy Potential Table.4 Table represents Renewable energy potential S.No Criteria Description 1 Roof Mounted PV system(low efficiency) 32,546 kwh/yr 2 Roof Mounted PV system(medium efficiency) 65,129 kwh/yr 3 Roof Mounted PV system(high efficiency) 97,693 kwh/yr 4 Single 15 Wind Turbine Potential 288 kwh/yr 5. Annual Carbon Emission 6. Annual Energy Use/Cost Figure.3 Chart represents the annual carbon emission 7. Energy Use : Fuel Figure.4 Pie chart represents annual energy use/cost Figure.5 Pie chart represents energy use/fuel 11

6 8. Energy Use : Electricity 9. Monthly Heating Load Figure.6 Pie chart represents energy use/electricity 10. Monthly Cooling Load Figure.7 chart represents monthly heating load 11. Monthly Fuel Consumption Figure.8 chart represents monthly cooling load Figure.9 chart represents monthly fuel consumption 12

7 12. Monthly Electricity Consumption 13. Monthly Peak Demand Figure.10 chart represents monthly electricity consumption 14. Annual Wind Rose(speed distribution) Figure.11 chart represents monthly peak demand Figure.12 chart represents annual wind rose speed distribution 15. Annual wind Rose (frequency distribution) Figure.13 chart represents Annual wind rose frequency distribution 13

8 16. Monthly Wind Roses Figure.14 chart represents monthly wind Roses 17. Monthly design data Figure.15 chart represents monthly design data 18. Annual temperature bins 19. Diurnal Weather Averages Figure.16 chart represents annual temperature bins Figure.17 chart represents diurnal weather averages 14

9 20. Humidity Figure.18 Chart Represents Annual Relative Humidity Frequency Distribution V. CONCLUSION Energy auditing provides accurate result than the conventional methods in terms of cost efficiency at the material usage in the pre phase of construction. The detailed energy consumption data stands as a platform to perform complex calculations which in terms provides practical results without any assumptions. The site specific energy auditing analysis proves to be the best method of analysis in the emerging construction design. REFERENCES [1] Assoc. Prof. Wong yew wah, schoo, Energy audit for buildings, BCA seminar on energy efficiency in building design, [2] Sustainable energy authority of Ireland, Commercial buildings special working groups, Development of new commercial buildings energy audit methodology based on the EED principle, [3] Adi Ainurzaman jamaludin, Nila Inangda, Ati Rosemary Mohd Ariffin, Energy performance: A comparison of four different multi-residential building designs and forms in the equatorial region, IEEE first conference on clean energy and technology CET [4] Li Wang, Win-Bin Lin, Energy saving of green buildings using Natural daylight. IEEE xplore, [5] Xin wang and chen huang, Energy audit of building: a case study of commercial building in shanghai. [6] J. Gomes, D. Coelho and M.Valdez, Energy audit in a school building technology, professional and artistic school of Pombal, INESC Coimbra, Portugal. [7] K. J. Chua, S. K. Chua, Energy performance of residential building in Singapore, 29 October