Page 80 - GRIHA Manual Volume III - Introduction to National Rating System
P. 80
Building and system design optimization 73
8. Once the inside design conditions are specified, run the simulation software and generate
annual energy consumption profiles. Calculate the building EPI (kWh/m /year) based on the
2
results obtained through simulations.
9. Check if this EPI value meets the EPI benchmark set under GRIHA for the specific building
category. If not, then the next step is to incorporate different energy-saving measures to the
building model and analyse their impacts.
10. Through a parametric analysis, impact of different energy conservation measures (ECMs) is
analysed through simulation. This exercise helps in identifying ECMs that contribute towards
improving the energy performance of the building.
The broad categories under which different energy-saving measures can be defined are as follows.
l Building design optimization: This refers to interventions related to building design like modifying
the building orientation, wall shading, roof shading, and so on. For detailed information on the
subject of building design optimization, refer the manual for GRIHA Criterion 13.
l Building envelope optimization: This refers to interventions related to modifications in the
building envelope—wall, roof, and glazing. The performance of the building depends on
density, thermal conductivity, and specific heat capacity of different layers in wall/ roof . So,
the choice of materials for building envelope should be as per the requirement of the climate
type in which the building is located. As per GRIHA, it is mandatory that effective SHGC of
the fenestration is compliant with the maximum SHGC requirement prescribed by ECBC-2007.
While choosing the materials for building envelope, it is recommended that the prescriptive
requirements of ECBC-2007 for wall, roof, and fenestration U-values are considered as the
minimum benchmark.
l Lighting system optimization: Lighting load can be optimized by appropriate design of lighting
system and selection of energy-efficient lamps and energy-efficient fixtures. The lighting
2
system should be designed such that the lighting power density (W/m ) is as recommended
by ECBC-2007, and visual comfort maintained inside the building is as per the comfort
recommended by the NBC-2005.
l HVAC system optimization: HVAC system optimization includes selection of appropriate system,
selection of energy-efficient components, integration of HVAC controls, installation of energy-
saving equipment like economizers, heat recovery wheel, and so on.
11. Once all the energy-saving strategies have been finalized, the final model should be developed
using optimized building envelope, lighting system, and HVAC system parameters. Run
2
simulation to calculate the EPI (kWh/m /yr) for this final proposed case.
12. Check if this EPI value meets the EPI benchmark set under GRIHA for the specific building
category.
Two mandatory points can be awarded if the building EPI meets the EPI benchmark set under
GRIHA for the specific building category and the thermal comfort conditions are fully met
as well.
For non-AC buildings
13. In case of non-air-conditioned buildings, the requirement is that the thermal comfort
conditions as specified in Table 14.2 of GRIHA Criterion 14 are met for 90% of all occupied hours
8. Once the inside design conditions are specified, run the simulation software and generate
annual energy consumption profiles. Calculate the building EPI (kWh/m /year) based on the
2
results obtained through simulations.
9. Check if this EPI value meets the EPI benchmark set under GRIHA for the specific building
category. If not, then the next step is to incorporate different energy-saving measures to the
building model and analyse their impacts.
10. Through a parametric analysis, impact of different energy conservation measures (ECMs) is
analysed through simulation. This exercise helps in identifying ECMs that contribute towards
improving the energy performance of the building.
The broad categories under which different energy-saving measures can be defined are as follows.
l Building design optimization: This refers to interventions related to building design like modifying
the building orientation, wall shading, roof shading, and so on. For detailed information on the
subject of building design optimization, refer the manual for GRIHA Criterion 13.
l Building envelope optimization: This refers to interventions related to modifications in the
building envelope—wall, roof, and glazing. The performance of the building depends on
density, thermal conductivity, and specific heat capacity of different layers in wall/ roof . So,
the choice of materials for building envelope should be as per the requirement of the climate
type in which the building is located. As per GRIHA, it is mandatory that effective SHGC of
the fenestration is compliant with the maximum SHGC requirement prescribed by ECBC-2007.
While choosing the materials for building envelope, it is recommended that the prescriptive
requirements of ECBC-2007 for wall, roof, and fenestration U-values are considered as the
minimum benchmark.
l Lighting system optimization: Lighting load can be optimized by appropriate design of lighting
system and selection of energy-efficient lamps and energy-efficient fixtures. The lighting
2
system should be designed such that the lighting power density (W/m ) is as recommended
by ECBC-2007, and visual comfort maintained inside the building is as per the comfort
recommended by the NBC-2005.
l HVAC system optimization: HVAC system optimization includes selection of appropriate system,
selection of energy-efficient components, integration of HVAC controls, installation of energy-
saving equipment like economizers, heat recovery wheel, and so on.
11. Once all the energy-saving strategies have been finalized, the final model should be developed
using optimized building envelope, lighting system, and HVAC system parameters. Run
2
simulation to calculate the EPI (kWh/m /yr) for this final proposed case.
12. Check if this EPI value meets the EPI benchmark set under GRIHA for the specific building
category.
Two mandatory points can be awarded if the building EPI meets the EPI benchmark set under
GRIHA for the specific building category and the thermal comfort conditions are fully met
as well.
For non-AC buildings
13. In case of non-air-conditioned buildings, the requirement is that the thermal comfort
conditions as specified in Table 14.2 of GRIHA Criterion 14 are met for 90% of all occupied hours
