Program Overview
Under the present labeling scheme ,the buildings are being labeled as per their actual Energy Performance Indices (EPI) on a scale of 1 to 5. The sets of standard EPI bandwidths developed to rate buildings under this scheme for different climatic zones indicate the range of variations in the energy performances of different office building types lying in a particular climatic zone.
To apply for rating of office buildings, a standardized format is developed for collection of actual energy consumption: data required includes building’s built up area, conditioned and non-conditioned area, type of building, hours of operation of the building in a day, climatic zone in which building is located, and other related information of the facility.
Based on the data provided by BEE, there are 261 buildings have been star rated under different categories of buildings as on date. BEE had launched the Star rating program for Offices (February 2009), BPOs (December 2009), Shopping Mall (January 2011) and Hospitals (July 2014). Memorandum of Understanding (MoU) is also signed between BEE and CPWD on 10th January,2019 for “Energy Efficiency in CPWD managed Buildings”
BEE star rating buildings
Star Rating System
Energy Performance Index (EPI) in kWh / sqm/ year is considered for rating the building. The table indicating the EPI with the corresponding Star Label under the various climatic zones are provided in below sections for reference- For buildings having air-conditioned area greater than 50% of their built-up area & For buildings having air conditioned area less than 50% of their built up area.
Baseline EPI for Star rating buildings
Under this programme, the user affixes the building rating label as per the label design and specification (both in terms of size and material), manner of display, and the rating plan as prescribed by the Bureau for the particular building type. BEE is continuously reviewing its technical approach to the development of the rating system to ensure an accurate, equitable, and statistically robust rating, because each building type has unique features that impact energy efficiency. BEE has also taken up the exercise of standardization of energy data collection which assists in comparative assessment and target setting in existing buildings.
Star Rating for building with>50% of air-conditioned built up area
Star Rating for building with<50% of air-conditioned built up area
Methodology for Energy Savings followed under Star Rating System for Existing Buildings
Methodology adopted for assessing the energy savings of star rated buildings is based on the difference between the reported EPI value and max EPI for star 1 rated building, multiplied by the total built-up area. The bandwidths considered for building energy star rating programme are as follows:
EPI shall be kWh/sqm/year in terms of purchased & generated electricity divided by built up area in sqm. However, the total electricity would not include electricity generated from on-site renewable sources such as solar photovoltaic etc. The rating is normalized to account for the operational characteristics that define the building use, hours of operation, climatic zone and conditioned space.
Total Built Area* (Conventional EPI – Me asured EPI f or Star Rated Building)
Where Conventional EPI = Max EPI for 1 Star Rated building for specific category of building in specific climate zone
Annual Energy Savings = (EPI Conventional – EPI Improved) x Total Built-up Area
Where, EPI Conventional = Max EPI of 1 Star Labelled building for specific category of building in specific climate zone
EPI Improved = Measured EPI of the Star Labelled building
Star Rating for building with >50% of air-conditioned build up area
Star Rating for building with <50% of air-conditioned build up area
Type of Buildings and Climate Zones:
The programme targets the following 4 climatic zones for air-conditioned and non-air-conditioned buildings:
- Warm & Humid
- Composite
- Hot and Dry
- Temperate
There are total of four types of commercial establishments that are part of this report, viz. Offices, Hospitals, BPOs, and Shopping Malls.
1. Office Buildings: BEE Star Rating Scheme for Office Buildings is notified in the year 2009. The baseline EPIs considered for star rating program in more than 50 % air-conditioned built-up area and less than 50 % air-conditioned built-up area is given below:
Table 1: EPI for star label office buildings
2. BPO Buildings: Star Rating Scheme for BPO buildings notified in December 2009. Average Annual hourly Energy Performance Index (EPI) i.e., (AAhEPI) in (Wh / hr/ sqm) has been considered for rating the BPO building. The table indicating the AAhEPI with the corresponding Star Label under the various climatic zones are presented as follows:
Table 2: EPI for star label BPO buildings
3. Shopping Malls: BEE Star Rating Scheme for Shopping Malls is notified in year 2011. Energy Performance Index (EPI) in kWh / sqm/ year is considered for rating the mall. The table indicating the EPI with the corresponding Star Label under the various climatic zones is presented in the table here:
Table 3: EPI for star label Shopping Malls
4. Hospitals: BEE had launched the Star rating program for Hospitals in July 2014. A benchmarking tool called the ECO bench, available online is used for evaluating the star rating for hospitals. This tool gives the performance distribution curve, EPI, Performance Rank and relevant Stars to hospital buildings.
Impact of BEE Star Rated Programme:
As the star rating is valid for 5 years and there are 49 number of buildings that had received star rating from 2015-16 to 2018-19; so, it has been assumed that these buildings have been sustaining the energy savings post the star rating certification.
Out of these buildings, total 22 commercial establishments have received BEE star ratings in FY 2018-19. These buildings were given BEE star rating during different months of the year; therefore, energy savings cannot be considered for entire one year.
As star rated EPIs are calculated on annual basis considering seasonal factors, therefore it cannot be broke-down on monthly basis. Therefore, in order to calculate the energy savings for star rated buildings certified during FY 18-19, 50% of total energy savings is considered.
On account of total number of star-rated buildings in last 4 years, the total energy (electrical) saved by these commercial establishments in the year 2018-19 is 82.5 MU. This has led to reduction of 0.068 Million Tonnes of CO2.
Note: As the electrical energy savings obtained under this programme is mainly due to replacement of inefficient electrical & mechanical appliances with BEE star rated electrical & mechanical appliances, therefore in order to avoid any duplication, the energy savings of Star Rating Programme is considered under S&L programme by BEE.