The Department of Science and Technology, Government of India, along with Rocky Mountain Institute (RMI) and Mission Innovation announced the eight finalists of the Global Cooling Prize on November 15, 2019, in New Delhi. The Global Cooling Prize is an international innovation competition to incentivize the development of a residential cooling solution that has one-fifth climate impact as compared to the typical residential/room air conditioners sold on the Indian market today. The Prize was launched in November 2018 by the Union Minister of Science and Technology, Dr. Harsh Vardhan. The Prize is administered by RMI, Conservation X Labs, Alliance for an Energy Efficient Economy (AEEE), and CEPT University, and supported by a coalition of over 20 leading international nonprofit organizations.

The Finalist teams of the Global Cooling Prize include some of the world’s largest air conditioner (AC) manufacturers, promising start-ups and corporations from China, India, Japan, the United Kingdom, and the United States. The Finalist teams selected, in alphabetical order, are:
• Barocal Ltd, a new spin-out from a University of Cambridge lab (UK)
• Daikin Air-conditioning India Private Limited, Daikin Industries Ltd., and Nikken Sekkei Ltd. (Japan, India)
• Godrej and Boyce Mfg. Co. Ltd. and A.T.E. Enterprises Private Limited (India)
• Gree Electric Appliances Inc. of Zhuhai and Tsinghua University (China)
• Kraton Corporation, IIT Bombay, Porus Laboratories, and Infosys (US, India)
• M2 Thermal Solutions (US)
• S&S Design Startup Solution Private Limited (India)
• Transaera Inc. and Qingdao Haier Air Conditioner Gen Corp. Ltd (US, China)

The Finalist teams were announced at the Finalist Award Ceremony by Dr. Harsh Vardhan; Dominique Asquith, High Commissioner of the United Kingdom in India; and Iain
Campbell, Senior Fellow at RMI, along with other dignitaries from the Government of India. The event also saw the participation of senior representatives and experts from the Government of India, global financial institutions, international organizations, industry and academia, along with reporters from top-tier media around the world.

Since the Prize was launched in 2018, over 2,100 participant registrations from around the globe were submitted by innovators, start-ups, research institutes, universities, and key industry manufacturers in over 95 countries. Of the registered entities, 445 teams submitted preliminary ideas and 139 teams from 31 countries followed through with a full Detailed Technical Application to the Prize. These eight Finalists were selected by the Prize’s Technical Review Committee after thorough analysis of all the 139 detailed technical applications. The Finalists have been awarded US$200,000 each to develop and ship their prototypes to India for testing in the summer of 2020.

About the Breakthrough Cooling Technologies

The eight teams selected are developing a wide range of technologies, including smart hybrid designs of vaporcompression technology, evaporative cooling technology, and solid-state cooling technology that use little or no global warming refrigerants, to demonstrate their potential to meet the specific technical criteria set for the Prize. The Prize criteria comprises of two primary criteria that require the cooling solutions to have one-fifth or 80% lower climate impact than that of the baseline AC unit (1.5 TR AC unit with an EER 3.5 W/W and using R22 refrigerant, which is the most commonly sold residential/room air conditioner on the market in India today), at no more than two times the assessed cost of this baseline unit. The cooling solutions also have to meet seven supplementary criteria that include requirements around the maximum power draw, daily water usage, materials, refrigerants, volumetric size, no on-site fuel combustion, and operating criteria requiring the technology to achieve indoor conditions of no more than 27°C dry bulb temperature and 60% relative humidity across the full-year weather profile.

The designs submitted by each of the Finalist teams employ advanced technology innovations to meet the Prize criteria. These innovations include technology to handle the sensible and latent cooling loads separately, use of climate-friendly refrigerants or alternatives, smart controls that optimize hybrid operation mode based on outdoor and indoor conditions, as well as integrated small solar PV panel to the outdoor unit of the cooling system, among others, allowing signifi cant reduction in climate impact whilst meeting the other criteria of the prize.

Independent handling of the sensible and latent cooling loads off ers the opportunity to signifi cantly improve the energy efficiency of the cooling system. To meet the latent cooling loads, one of the Finalist solutions uses a novel desiccant material in the form of a ‘moisture storage battery’ that can handle the moisture-laden air efficiently and regenerate itself (i.e. release the adsorbed moisture) using the waste heat of the condenser unit of an air conditioner. Another Finalist solution is using a patented membrane system to remove the humidity, thus allowing the dehumidified air to be sensibly cooled using low energy evaporative cooling approaches. Another approach to independent handling of sensible and latent cooling loads proposed by some of the Finalists is to use multiple independently controlled evaporator systems such that air temperature and moisture control can be handled separately based on the load requirement, thus improving the performance of the system.

Direct or indirect evaporative cooling approaches are being adopted by several Finalists where the evaporative cooler is being integrated with the vapor compression system to optimize the overall energy performance of the cooling solution. The solutions proposed by the Finalists use the direct evaporative cooling approach to either cool the outdoor air before it comes into contact with the condensing unit, particularly during high ambient conditions, or to cool the room directly by sensing the outdoor weather conditions effectively bypassing the vapor compression system, or both. One of the Finalist solutions has proposed the use of indirect evaporative cooling upstream of the vapor compression system and direct evaporative cooling of the outdoor air at the condensing unit. This approach not only reduces the sensible load to be met by the vapor compression system but also improves the condensing efficiency, thereby improving the overall energy efficiency of the system. The use of water as a working fluid in the evaporative cooler has been optimized by recovering the condensate and reusing it in the operation cycle, thus avoiding any excessive water consumption.

One of the Finalist solutions has adopted a solid-state cooling approach to cooling instead of traditional vapor compression or evaporative cooling approaches. In the proposed Barocaloric cooling solution, instead of applying pressure to liquid or gaseous refrigerants to achieve phase change, pressure is applied to organic ‘plastic crystal’ materials to cause solidstate phase transition that results in large thermal change in the material, producing a cooling effect. These organic plastic crystals are flexible materials that are widely available and are low-cost and non-toxic.

Smart logic and sophisticated control systems are a key design feature of all Finalist cooling solutions. By introducing a logic and control system that can sense the outdoor conditions, some of these cooling solutions are able to operate in hybrid mode by auto-switching between ventilation, evaporative cooling, and vapor compression modes, depending on the indoor and outdoor environment, thereby optimizing the overall energy performance of the cooling technology.

A key aspect of the cooling solutions from the Finalist teams is the choice of refrigerant. The solutions selected as Finalists demonstrate the use of low global warming potential (GWP) refrigerants in their designs such as R-152a (GWP <150), R-290 (GWP <3), HFO 1234ze (GWP <1), solid refrigerant 2-Bromoadamantane (GWP 0) and alternate working fluids such as water that will have dramatically lower climate impact over the lifetime of the AC as compared to the dominant refrigerants such as R-410A or R-22 used today. The Prize has become a test bed to examine the use of these low-GWP refrigerants for residential application, and thus, has the potential to accelerate
the HFC phase-down under the Kigali Amendment to the Montreal Protocol.

Next Steps of the Global Cooling Prize

The Finalist teams will be developing two working prototypes of their cooling solution and shipping these to India for testing purposes on or before April 15, 2020. These prototypes will be tested in accordance with the Testing Protocol of the Global Cooling Prize during the months of May through August in New Delhi and Ahmedabad in India. The protocol comprises of three diff erent testing methods: (i) Indian Seasonal Energy Efficiency Ratio (ISEER) laboratory test, (ii) Lab simulated year-round
performance test; and (iii) Field test.

In the lab simulated year-round performance test, one prototype from each of the Finalists will undergo a dynamic year-round performance test at the state-of-the-art testing
facility at CEPT University in Ahmedabad, India. The prototype will be tested in the lab environment for a period of up to 12 days reflective of all weather conditions in India. In the field test, the second prototype will be installed and tested in an actual residential apartment home in a mid to high rise apartment building in New Delhi, India. The Technical Review Committee will evaluate and adjudicate the performance of these prototypes during the testing stage. Based on the performance of these solutions on the prize criteria through the testing stages of the Prize, the ultimate grand winner(s) of the Global Cooling Prize will be selected in November 2020. The grand prize winner(s) will receive an award of US $1 million to commercialize and scale their technologies.

To learn more about the Finalist teams and their technologies, please visit globalcoolingprize.org