performance-based standards for energy efficient buildings
Transcript of performance-based standards for energy efficient buildings
Performance-based Standardsfor Energy Efficient Buildings
By S.K. ChouDepartment of Mechanical Engineering
National University of Singapore
Seminar on Building Control (Amendment) Act 2003 held on 13 February 2004
Introduction-Situation andObservations
Air conditioning typically contributes about half of theenergy consumption of a commercial buildingBuilding Sector accounts for more than one third ofthe total electrical consumption in SingaporeNeed for appropriate design guidelines and energystandards to take advantage of advancing technology,ease the compliance process and ensure thatcommercial buildings are designed and operated to ahigh standard of comfort and efficiency
Introduction-Situation andObservations
Appropriate engineering tools are required forthe design and operation of buildingsBuilding services maintenance can lead toimproved energy management and energysavingsSkills training and experience required to acton opportunities and maximise benefits
Energy Conservation in Buildings-Historical Development
1979: Prescriptive Standards incorporated inthe Building Control Regulations1982,1983: Launch of CP 24 Parts 1,2 and 3Mid 80s: Development of new OTTV1999: Compliance of CPs 13, 24 and 382001: Commencement of BCA-funded projecton energy efficiency index for non-residentialbuildings
Development of Guidelinesand Standards
Design of Building Envelopes
Design for Energy Efficiency
Design Tools
Design of Building Envelopes
Existing OTTV
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Design of Building Envelopes
New ETTV
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SCCFWWRSFUfWWRTUwWWRTDeqETTV
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Design for Energy Efficiency
Designing for Energy Performance - TheSystem Analysis ApproachEnergy Efficiency Index (EEI) BandsEnergy Management
Preparation for Prescriptive StandardCompliance
Check compliance with PrescriptiveStandard
No
Preparation for Energy Performance StandardCompliance
EndModifyDesignBuilding
EndYesApply Saving
options or modifyDesign Building
No
NoYes
Comply withPrescriptive Standard?
Comply with EnergyPerformance
Standard?
Designing for Energy Performance-The System Analysis Approach
Energy Efficiency Index (EEI) BandsAverage EEI 293.6kWh/m2/year for GFA < 20,000m2
Average EEI 233.6kWh/m2/year for GFA > 20,000m2
E ne rgy Inde x of S e le cte d C omme rcial B uild ings
0
100
200
300
400
500
600
Bu ild in g s
KW
h/m
2/y
< 20000m 2 > 20000m 2
Design for Energy Efficiency
Energy Efficiency Index (EEI) Bands
Short Term Targets (< 3 yrs)< 20,000m2: 300 to 320kWh/m2/year> 20,000m2: 240 to 260kWh/m2/year
Long Term Targets (> 5 yrs)< 20,000m2: 260 to 280kWh/m2/year> 20,000m2: 220 to 240kWh/m2/year
Design for Energy Efficiency
Design for Energy Efficiency
Energy ManagementEnergy AuditingTrainingMaintenanceBAS
Design Tools
DOE-2Simulation Codes
(Proprietary and public domain) BEST Software
Computation and Compliance– An example by BEST
ETTV and RTTV Calculation.Annual Energy Consumption Estimation.Peak Design Loads Estimation.Lighting and Receptacle Power AllowanceCalculation.Parametric Analyses.Energy Saving Options.
Sample Form (ETTV Input Form)
Sample Form (Energy Performance)
Sample Form (Shading)
Sample Form (Summary)