Baseline AC UnitLearn More
All the performance metrics will be compared with the baseline AC unit
Climate Impact: Energy and Refrigerant
Must have 5X lower climate impact than the baseline unit: Energy and Refrigerant Criteria
The cooling solution must show the potential for at least 80% lower climate impact than the climate impact of the baseline unit. The climate impact is evaluated through a combination of reduction in grid electricity consumption (kWh) and reduction in global warming potential (GWP) of the refrigerant used. The 80:20 weighting will be used for electricity and refrigerant respectively, to arrive at the overall climate impact of the cooling solution. The reduction in grid electricity consumption will also be assessed through a side-by-side operation testing - a combination of lab and real-world testing.
Residential cooling demand is expected to increase by 5X in developing countries over the next 30 years. A cooling solution that has 5X lower climate impact is needed to reverse the trend in increasing greenhouse gas (GHG) emissions due to this unprecedented growth in cooling demand. We believe 5X strikes the right balance between being a breakthrough that has not yet been done and being one that is achievable. Current best available air conditioning units are already approaching 3.5X lower climate impact than baseline. We reviewed a number of breakthrough technologies and have sketched out theoretical paths to achieving up to 5X less grid electricity use based on combining technology that already exists today. This when combined with a low GWP refrigerant could take us beyond the 5X climate impact requirement.
The weighting for electricity and refrigerant is based on RMI modeling and the report of the Technology and Economic Assessment Panel (TEAP) in 2018, which show that refrigerant emissions are ~ 20 percent of life-cycle GHG emissions for room air conditioners, and operational emissions are ~ 80 percent, taking into account developing market grid emissions intensity factors.
Evaluation and Scoring
To achieve a 5X lower climate impact, an overall reduction of 80% (electricity kWh and refrigerant GWP combined) as compared to the baseline will be required. For example, if a technology achieves a 75% reduction in grid electricity from the baseline and also uses a zero GWP refrigerant, it achieves a 100% reduction from the GWP baseline (R22 at a GWP of 1760). The overall percentage reduction achieved using the assigned 80:20 weighting would be 80% or 5X lower climate impact. This weighted percentage reduction from the baseline will then be converted to equivalent points. A zero percent reduction from the baseline i.e. a technology at baseline will receive zero points. A technology achieving 100% reduction from the baseline will receive 100 points. Any percentage reduction between 0% and 100% will be ratably converted to equivalent points between 0 to 100.
If a participant can demonstrate in their application that the cooling technology effectively delivers the full 5X lower climate impact through a combination of the standalone unit performance and reducing energy consumption in adjacent systems (example: reduced energy consumption for hot water generation), the Technical Review Committee may decide to consider such application as complying with the climate impact criteria. In such a case, the technical review committee will include the corresponding incremental climate impact and to the degree appropriate award additional points.
This scoring methodology will be used to evaluate the Detailed Technical Application of the participants and rank the top 10 finalists. To the extent that the total number of qualifying finalists selected, that meet or exceed the 5X lower climate impact criteria, falls short of the desired number of teams to go through to the final round, the Technical Review Committee may decide to invite designs that meet all other threshold criteria for the prize (mentioned below), show high early stage potential to exceed 80% climate impact reduction in the future and currently exceed at least a 64% climate impact reduction from the baseline, to develop prototypes for testing.
Following field and lab testing of the baseline unit and proposed solution, the top 10 cooling solutions will receive an updated score following the same scoring methodology.
If a technology achieves a 75% reduction in grid electricity from the baseline and also uses a zero GWP refrigerant, it achieves a 100% reduction from the GWP baseline (R22 at a GWP of 1760). The overall percentage reduction achieved using the assigned 80:20 weighting would be 80% or 5X lower climate impact. Therefore, this technology will receive 80 points. Similarly, if the technology is powered by solar PV mounted on it without exceeding the overall unit volumetric sizing criteria and uses zero GWP refrigerant, it achieves an overall reduction of 100% from the baseline and will receive 100 points.
Installed cost to consumers must not be more than 2X that of the baseline AC unit when manufactured at a scale of 100,000 units
The installed cost of the cooling solution to consumer at a manufacturing scale of 100,000 units must be no more than 2X the baseline AC unit’s cost. The participant must provide the unit bill of materials cost, cost of external components and cost of consumables required to operate the solution, at a proposed manufacturing scale of 100,000 units per year. The bill of materials cost (comprised of the above noted three types of cost) of the competing technologies will be independently assessed by a panel of industrial engineers at a manufacturing scale of 100,000 units using the submitted bill of materials. The typical margins, labor costs and distribution costs will be added to this assessed cost to arrive at the total installed cost to the consumer excluding the standard installation labor cost and any Goods and Services Tax (GST).
The cost of any renewable generation source incorporated as part of the design will be considered in determining the total cost to the extent that it is required to achieve the threshold 5X lower climate impact i.e. the total cost of the solution including the appropriate proportion of renewable source cost must be no more than 2X the cost of the baseline AC unit.
Based on the assessment of the latest market availability for the baseline room air conditioner (RAC) sold by the industry leader with the highest market share in India, and in anticipation of our purchase of identical units for baseline unit testing the baseline cost is determined to be INR 36,515 or $534 based on 2018 average USD to INR currency exchange rate.
Even at an initial 2X higher cost to consumers, RMI analysis shows that a 5X lower climate impact cooling solution would help consumers save money with a less than three-year payback period. Using the electricity rates for residential consumers to be INR 6 per kWh (typically in Delhi), our analysis shows that consumers will see a total net-present-value savings of about US$1,500 over a 10-year lifetime.
Evaluation and Scoring
Points will be awarded to the cooling technology based on assessed cost estimates. A hypothetical zero cost will receive 40 points and a five-times cost from the baseline will receive zero points. Any assessed cost figure between zero and five times of the baseline cost will be ratably converted to equivalent points.
If a competing technology is not able to achieve the 2X cost limit at assessed scale but the participants can demonstrate in their application that the cooling technology brings reduced cost benefits in adjacent systems, the Technical Review Committee may decide to consider such applications as complying with the criteria and reflect the corresponding reduction in costs.
A technology that has the assessed cost (at manufacturing scale of 100,000 units) at par with the baseline cost i.e. INR 36,515 or $534, will receive 32 points. A solution that costs twice the baseline unit (2X) i.e. INR 73,030 or $1,068, will receive 24 points using the scoring method described above.
Should consume no more than 700 W of power from the grid
The maximum power drawn by the solution from the electricity grid should not exceed 700 W while delivering the rated cooling capacity of 1.5 TR (5.3 kW) under standard outdoor conditions as well as over the span of lab and real-world test. The maximum or peak power draw will be measured by using demand meters which sample at a very high frequency (fraction of a second) to determine the maximum power drawn by the equipment in a given time period. The maximum draw, 700 W, represents a 60 percent reduction from baseline, and a 30 percent reduction from typical high performing units available in the market.
Reducing power demand is critical in avoiding new power generation and distribution systems that would otherwise be needed to meet increased demand for cooling. Based on our analysis using the NREL's BEOPT tool, and review of currently available air-conditioning technology, we believe a 60 percent power reduction is achievable. Our research also shows that a 2X decrease in power is associated with a 3X reduction in energy consumption. Extending this relationship to about 5X level of efficiency suggests that a 60 percent reduction in power draw is achievable.
Based on our research, typical high-performance units available today are at ~1000 - 1200 W max power draw.
In addition, alternative technologies such as solar photovoltaics (PV), battery storage, and deep space radiative cooling could offer further opportunity for reducing maximum power draw.
Should consume no more than 14 liters of water per day when averaged over a year, with a daily maximum limit of 28 liters, if any is required for operation
The onsite water consumption, if any is required for operation of the proposed solution, should not exceed 14 liters per day when averaged over a year with a maximum daily limit of 28 liters.
The cooling technology should be water neutral; that is, the technology must not use more water than it saves at the utility level through reduced energy consumption. Additionally, the new AC unit must use less than 10 percent of the water used for domestic purposes by a single household.
On average, the power sector in India consumed 2.1 cubic meters of water per megawatt-hour (2.1 liters per kilowatt-hour) of energy produced in 2014. Since the new AC unit will have 5X lower climate impact, the increased efficiency will reduce water consumption by 28 liters per day (during summer months).
To be conservative, in a high renewable-energy scenario in 2030, the power sector will consume 1.57 liters of water per kilowatt-hour of electricity produced. Using this number, the higher-efficiency AC unit will save 20 liters of water per day during the summer months. A household in India consumes an average of 400 liters of water per day for domestic purposes.
Should have zero onsite emissions from any fossil fuel based captive power source or heat source
The cooling solution should not combust fossil fuels onsite to generate a heating medium or electricity for operation of the unit.
The proposed cooling solution should not use any onsite combustion technology to operate the unit. Including distributed combustion sources not only possesses potential safety concerns for residential applications, but also undermines the impact of increasing penetration of renewables in the electricity grid and the corresponding reduction in grid emissions intensity.
Should use a refrigerant that has zero Ozone Depleting Potential (ODP), is of lower toxicity (Class A) and complies with IEC 60335-2-40 or ISO 5149
The cooling solution should use a refrigerant that has a zero ODP in line with the Montreal Protocol.
The cooling solution should use a lower toxicity (Class A) refrigerant as per ISO 817:2014 standard.
The cooling solution should be capable of meeting test market regulations, or in their absence, international guidelines IEC 60335-2-40 (2018 or latest amended version) or ISO 5149:2014 pertaining to safety and environment performance of systems using flammable refrigerants. It is preferred that the compliance to these standards is met for safe operation, however, the participating team will not be disqualified in case of a non-compliance with these standards.
In addition to the above requirements, including the GWP of the refrigerant reflected in the Climate impact calculation, the Technical Review Committee may also take into consideration the charge quantity where materially different to that of the baseline unit.
To mitigate the environmental impact from cooling, the refrigerant that is used should abide by the Montreal Protocol of zero ODP refrigerant. The refrigerant used should also meet the Class A toxicity criteria and comply with the test market or international safety standards to ensure it is safe to use in the air conditioners deployed in the residential sector.
Should be usable in existing homes, rather than requiring a "designed in" engineering solution
The total volumetric size of the cooling solution should not be more than two times the volumetric size of the baseline unit i.e. the total volumetric size should not exceed 0.52 cubic meters. The total volumetric size must include any dedicated renewable power generation resources and any external components that make up the proposed solution.
In addition, the installation of the cooling solution should not require any major infrastructure upgrades or structural modification to existing dwellings. For example, the installation of the super-efficient and climate friendly air conditioner units cannot mandate replacement of walls or major structural, electrical, or plumbing upgrades to existing multifamily apartment buildings.
The cooling solution is expected to be installed in new construction buildings as well as in existing building stock. Since the prevalent vapor-compression technology does not require major in-apartment electrical or plumbing work, the new super-efficient and climate friendly air conditioning units should be able to scale in the same market conditions.
The cooling solution should be of a reasonable size such that it can be easily transported and installed in most buildings. In order to ensure a viable solution that is widely applicable, total volumetric size is limited to twice the size of baseline RAC unit, i.e. less than 0.52 cubic meters, for this competition and is determined based on the combined volume of the indoor unit and outdoor unit of the baseline RAC unit procured for this competition.
Use of materials with excessively high embodied carbon or rare earth materials should be minimized
There will be no threshold requirements in relation to embodied carbon and rare earth materials, but the Technical Review Committee will, at their discretion, include life cycle impact assessment of any solution if they believe, in their judgement, that the solution includes materials with excessively high embodied carbon or rare earth materials, in their final determination of suitability for progression to award.
The cooling solution should not result in unintended consequences in the future by the use of materials that have excessively high embodied carbon or by using high quantities of rare earth materials. A life cycle impact assessment of any technology allows us to understand these consequences in greater depth. The cooling solutions should therefore focus on optimizing, and where possible, minimizing the use of such materials, in developing the next generation innovative cooling solutions.
Should be designed to meet a 1.5 TR (5.3 kW) cooling load at standard outdoor conditions and maintain below 27°C DBT and 60% RH indoor conditions
The solution should be able to deliver the cooling capacity of 1.5 TR (5.3 kW) under the standard test outdoor conditions of 35°C dry bulb temperature (DBT) and 24°C wet bulb temperature (WBT) as specified in IS 1391 (Part 1): 2017, IS 1391 (Part 2): 2018 and ISO 16358:1 - 2013. The IS 1391 standard, as applicable to the testing of prototype design (example: unitary or split type), will be followed accordingly.
During the Detailed Technical Application stage, the submission should demonstrate that the cooling solution is able to maintain below 27°C DBT and 60% RH indoor conditions at all times when the outdoor air temperature is above 20°C DBT only. Further, an unmet hours allowance of 3.4% of the annual hours will be provided on the operation criteria to all the participating solutions and will only be evaluated when the outdoor air temperature is above 20°C DBT.
During testing in the lab and real-world apartments (see Testing Protocol Overview below), the prototype of your cooling solution 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. The prototypes as well as the baseline unit will be operated in a continuous operation mode for all the days of the testing period to determine their energy consumption while assessing their ability to maintain the desired indoor conditions. An “unmet hours” allowance of 3.4% of the test period hours will be provided, 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, and will only be evaluated when outdoor air temperature is above 20°C DBT, recognizing that the ramp up period and precision of operation of prototypes is likely to be less than that of the established baseline unit.
In order to maintain comfort and a healthy indoor environment, humidity must be controlled. Also, a temperature of 27°C DBT is increasingly being used internationally as the standard indoor set point for air-conditioning ratings. We recognize that the baseline unit has been developed over the years to deliver a stable performance under different operating conditions and hence unmet hours allowance is considered recognizing the performance glitches that prototypes may encounter during early stage. We also want to recognize that room air-conditioners are typically not operated in high ambient climates when the outdoor air temperatures are below 20°C DBT and so we will not evaluate the performance of the baseline unit or cooling solutions when the outdoor air temperatures are below 20°C DBT for the purpose of the prize.