Prototypes will be evaluated based upon a series of tests that include an Indian Seasonal Energy Efficiency Ratio (ISEER) laboratory test, a lab simulated year-round performance test, and a field test.Learn More
The Technical Review Committee will evaluate the Detailed Technical Applications of the participants and select up to 10 teams. These finalists will then each be awarded up to US$200,000 which they will use to support the development and production of two prototypes of their cooling solution and ship it to India (if manufactured outside India) for the testing purposes. The testing phase will span over a period from May to September 2020.
Indian Seasonal Energy Efficiency Ratio (ISEER) laboratory test
The ISEER rating test, developed by the Bureau of Energy Efficiency (BEE) in India, assesses the cooling energy consumption and cooling load met by the air conditioner across a temperature range of 24°C to 43°C for 1,600 annual operating hours.
The first prototype of each selected participant will be sent to a National Accreditation Board for Testing and Calibration Laboratories (NABL) accredited lab for ISEER rating. The laboratory will conduct testing in accordance with ISO 16358-1:2013, IS 1391 (Part 1): 2017, and IS 1391 (Part 2): 2018 and will determine the prototype’s ability to deliver 1.5 TR cooling capacity under standard test conditions. The IS 1391 standard, as applicable to the testing of prototype design (example: unitary or split type), will be followed accordingly. The prototypes that receive an ISEER rating of less than 7 will be disqualified considering the fact that it is lower than the best available technology in market in India already.
The prototypes using novel and alternative technologies which cannot be tested in accordance with the standard ISEER requirements will be evaluated on a case by case basis at the sole discretion of the Technical Review Committee.
Lab simulated year-round performance test
The second prototype of each selected participant will be tested in a state-of-the-art laboratory environment at the CEPT University laboratory in Ahmedabad, Gujarat in India. Each competing technology including the baseline unit - which is a 1.5 TR fixed-speed EER 3.5 W/W mini-split AC unit of brand Voltas and model SAC 183 JZJ - will be tested for up to 12 days. The choice of the baseline unit is based on most commonly sold room AC by the market player with higher share in India.
The laboratory set-up will include two climate-controlled chambers:
- Internal chamber: where the air conditioning unit will be installed
- External chamber: which simulates the outdoor conditions
The prototype units including the baseline unit will be tested in the lab environment to evaluate their performance through a series of conditions simulating the range of a full year. The internal conditions will be simulated to represent a typical daily sensible and latent load profile observed in a home for internal gains (lighting, infiltration, appliances, occupants etc.) using electric resistance heat, controlled infiltration, and humidifier. The external conditions, for this test, will be simulated based on a set of 10 daily weather profiles that start from a mild day (with respect to dry bulb temperature (DBT) and relative humidity (RH)) and end at an extreme day (with respect to DBT and RH) with conditions becoming more challenging each successive day.
These select 10 days profile can be found here.
The prototypes and the baseline unit should be able to maintain below 27°C DBT and 60% RH indoor conditions when the outdoor air temperature is above 20°C DBT for the duration of the test period. All the units will be operated for these 10 typical days in continuous operation mode, excluding day to day transition and stabilization, and the performance will be extrapolated using an assigned weighting for each day to give annual performance. The middle days of the testing period represent the aggregate seasonal variation in DBT and RH and will account for the majority of the weighting for annual days. The weighting for the mild day (starting day), where prototypes will commence operation, is likely to have a weighting of no more than 5% and each extreme day, which represent the most challenging conditions, is likely to have a weighting of no more than 1% when extrapolating to annual performance. The uncertainty of measurements during the test will be evaluated using the methods specified in ISO/IEC Guide 98-1 to 4.
Unmet hours allowance: In addition to the number of hours that the baseline unit does not achieve the desired indoor conditions of below 27°C DBT and 60% RH, an additional allowance of 3.4% of the test period hours will be provided recognizing that the ramp up period and precision of operation of prototypes is likely to be less than that of the established baseline unit. The unmet hours will only be evaluated when the outdoor air temperature is above 20°C DBT. The below formula can be used to estimate the number of additional unmet hours of the technology during the test period.
Weighted unmet hours of a test day = Actual number of unmet hours on a test day * test day weighting * number of test days
The ability of the baseline unit and the prototypes to maintain indoor conditions below 27°C DBT and 60% RH and their performance against the technical criteria, will be compared to determine the relative performance. The performance aspects of the baseline unit and the prototypes will not be evaluated for the period when the outdoor air temperature is below 20°C DBT regardless of whether the solution continues to operate or not.
The prototypes will also undergo a field test in an actual residential apartment in India. The apartments will be selected in a mid to high rise building and will be representative of the apartments that are south-facing with proportionately equivalent exterior wall surface area and have a typical cooling load that can be met by a 1.5 TR air conditioner. The Prize organizers will ensure that similar conditions are observed during the test across all apartments.
The testing of the competing technologies in these apartments will be carried out in parallel with the baseline unit which is a 1.5 TR fixed-speed EER 3.5 W/W mini-split AC unit of brand Voltas. The model details of the baseline unit are - Voltas SAC 183 JZJ. The choice of the baseline unit is based on most commonly sold room AC by the market player with higher share in India.
Prior to installation and testing of the competing prototypes in the apartments, the organizers will ensure the following:
- The apartments will remain unoccupied to limit variation in loads due to human behavior.
- The apartments are identical in size and materially equivalent in every other aspect including the solar gain, shading conditions, envelope characteristics etc. Thermal imaging to be done to ensure similar envelope characteristics between test units.
- A blower door test is conducted in each apartment unit to ensure an equivalent air tightness. Wherever necessary, envelope will be properly sealed or leaked to ensure that air tightness characteristics are equivalent across all the apartments.
- Airflow measurements are taken for kitchen and exhaust fans, and adjustments are made to ensure even flow rates between units.
- Any modification that may be required to fit the prototype unit will be noted.
After conducting the checks, the organizers will install and test the performance of prototypes and baseline unit in these apartments. The objective is to assess the prototype’s ability to maintain the indoor conditions below 27 °C DBT and 60% RH for the duration of the test period when outdoor air temperature is above 20°C DBT in a hot and humid / hot and dry climate in India while demonstrating performance against the technical criteria. In addition to all the performance metrics of the technical criteria, on any given day of the field test the cooling solution should not consume more than 28 liters of water, if required for operation. The uncertainty of measurements during the test will be evaluated using the methods specified in ISO/IEC Guide 98-1 to 4.
Unmet hours allowance: In addition to the number of hours that the baseline unit does not achieve the desired indoor conditions of below 27°C DBT and 60% RH, an additional allowance of 3.4% of the test period hours will be provided recognizing that the ramp up period and precision of operation of prototypes is likely to be less than that of the established baseline unit during the field test. The unmet hours will only be evaluated when outdoor air temperature is above 20°C DBT.
The ability of the prototypes to maintain indoor conditions below 27°C DBT and 60% RH and their performance against the technical criteria, will be compared to the baseline unit installed in a materially equivalent apartment and subject to the same external and internal loads in order to determine its relative performance. The performance aspects of the baseline unit and prototypes will not be evaluated for the period when the outdoor air temperature is below 20°C DBT regardless of whether they continue to operate or not.