Alternative Refrigerant Evaluation for HighAmbient-Temperature. Environments. Side Event at the 38th OEWG Vienna, Austria 18 July 2016

Transcription

1 Alternative Refrigerant Evaluation for HighAmbient-Temperature Environments Side Event at the 38th OEWG Vienna, Austria 18 July 2016 ORNL is managed by UT-Battelle for the US Department of Energy

2 Presented by Dr. Omar Abdelaziz, ORNL Group Leader, Building Equipment Research, Energy and Transportation Science Division and Dr. Suely Machado Carvalho, IPEN (BRAZIL); Senior Researcher Co-chair, International Expert Panel on Alternative Refrigerant Evaluation for HAT ORNL is managed by UT-Battelle for the US Department of Energy

3 Program Objective Evaluate the performance of alternative lower-gwp refrigerants for mini-split air conditioning under high ambient temperatures. Evaluate the performance of alternative lower-gwp refrigerants for packaged rooftop air conditioning under high ambient temperatures. Help evaluate the viability of using alternative lower-gwp refrigerants in said markets to avoid the costly transition from HCFC to HFC and then from HFC to lower-gwp refrigerants 3 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

4 Panel of International Experts Dr. Radhey Agarwal (India) Fotouh Al-Ragom (Kuwait), Dr. Karim Amrane (USA) Dr. Enio Bandarra (Brazil) Dr. J. Bhambure (India) Mr. Ayman El-Talouny (UNEP) Daniel Giguère (Canada) Dr. Tingxun Li (China) Co-Chairs Dr. Suely M. Carvalho (IPEN, Brazil) and Dr. Patrick Phelan (Department of Energy, USA) Panel Members 4 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries Dr. Samuel Yana Motta (Peru) Mr. Maher Moussa (Kingdom of Saudi Arabia) Mr. Ole Nielsen (UNIDO) Mr. Tetsuji Okada (Japan) Dr. Alaa Olama (Egypt) Dr. Alessandro Giuliano Peru (Italy)

5 Panel Tasks Provide independent technical input for the ORNL study Recommend alternative refrigerants to be evaluated Review and comment on appropriate evaluation procedures Assess results Review the interim working paper and the final report 5 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

6 Timeline for Phase I: Mini-Split AC evaluation Early March: First Conference Call Mid April: Meeting in Bangkok Mid June: Review Interim Report Early July: Publish Interim Report Early August: Meeting in Yokohama Early September: Review Final Report Mid October: Final Report Published Meeting of the Parties 6 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

7 Final Report Available ORNL/TM-2015/536 publications/files/pub pdf 7 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

8 R-22 Alternative Refrigerants ASHRAE GWP Refrigerant Manufacturer Safety Class AR4 AR5 R-22 a - A1 1,810 1,760 N-20b b Honeywell A DR-3 b Chemours A2L ARM-20b b Arkema A2L L-20a (R-444B) b Honeywell A2L DR-93 b Chemours A1 1,258 1,153 DR-7(R-454A) b Chemours A2L R-290 a - A3 3 3 a Sources: IPCC AR4, 2007; IPCC AR5, 2013 b GWP values for refrigerant blends not included in IPCC reports are calculated as a weighted average using manufacturer-supplied compositions. 8 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

9 R-410A Alternative Refrigerants Refrigerant Manufacturer ASHRAE Safety Class GWP AR4 AR5 R-410A a - A L41-2 (R-447A) b Honeywell A2L L41-Z (R-447B) b Honeywell A2L DR-55 b Chemours A2L ARM-71a b Arkema A2L HPR-2A b Mexichem A2L R-32 a Daikin A2L a Sources: IPCC AR4, 2007; IPCC AR5, 2013 b GWP values for refrigerant blends not included in IPCC reports are calculated as a weighted average using manufacturer-supplied compositions. 9 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

10 Test Conditions Test condition Outdoor Dry-bulb temp. Dry-bulb temp. Indoor Wet-bulb temp. Relative humidity C C C % AHRI B AHRI A T3* T Hot Extreme Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

11 Test Conditions Test condition Outdoor Dry-bulb temp. Dry-bulb temp. Indoor Wet-bulb temp. Relative humidity C C C % AHRI B AHRI A T3* T Hot Extreme Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

12 Alternative Refrigerant Evaluation for Mini-Split AC Systems at High Ambient Temperature Environment

13 Equipment Carrier mini-split AC systems Designed for high ambient performance up to 55 C Rated Capacity at ISO T1 (~AHRI A) = 5.28 kw (18 kbtu) R-410A unit: COP of 3.37 (EER ~ 11.5) R-22 unit: COP of 2.78 (EER ~ 9.5) 13 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

14 Instrumentation: Mini-Split AC R-22 system Custom-built air enthalpy tunnel complying with AHRI Standard 210/240 and ANSI/ASHRAE Standard 37: air flow measurement uncertainty ±0.4% Coriolis mass flow meter: CMF25 with ±0.5% error Pressure sensors: ±0.08% BSL T-type thermocouples: ±0.28 C (0.5 F) Dew point sensors: ±0.2 C (0.36 F) Barometric pressure sensors: ±0.6 hpa/mb Power meters: ±0.2% reading Instrumentation calibrated either by ORNL metrology or by a third-party calibration laboratory before the experimental campaign began. 14 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

15 R-22 Experiment Setup 15 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

16 R-22 Experiment Setup 16 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

17 R-22 Experiment Uncertainty Air-side uncertainty: Capacity = ±2.3% COP = ±2.4% Refrigerant-side uncertainty: Capacity = ±0.7% COP = <±0.8% Energy balance between air-side and refrigerant-side measurements: AHRI A: 2.3% to 2.89% AHRI B: 1.99% to 2.37% Energy Balance = Q air Q ref Q air 100% 17 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

18 Instrumentation: Mini-Split AC R-410A system Code tester complying with AHRI Standard 210/240 and ANSI/ASHRAE Standard 37 Coriolis mass flow meter: CMF25 with ±0.5% error Pressure sensors: ±0.08% BSL RTD: ±0.15 C ( C Wet-bulb sensors: ±0.15 C ( C Barometric pressure sensors: ±0.6 hpa/mb Power meters: ±0.2% reading Instrumentation calibrated either by ORNL metrology or by a third-party calibration laboratory before the experimental campaign began. 18 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

19 R-410A Experimental Setup 19 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

20 R-410A Experimental Setup 20 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

21 R-410A Experiment Uncertainty Air-side uncertainty: Capacity: ±1.6% COP: ±1.5% Refrigerant-side uncertainty: Capacity: ±0.65% COP: ±0.81% Energy balance between air-side and refrigerant-side measurements: AHRI A: 3.6% to 0.05% AHRI B: 3.97% to 0.05% 21 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

22 Soft Optimization of Alternative Refrigerants Optimization sequence: Optimize charge Find best capillary tube Increase/decrease charge Find best capillary tube Check performance at T3 to ensure superheat and subcooling to maintain capacity at extreme conditions 22 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

23 R-22 Mini-Split AC Unit Results Baseline: R-22 with mineral oil

24 R-22 Unit Refrigerant ASHRAE safety class Capillary Tube Length, mm (Inch) Charge mass kg (oz) R-22 (baseline) A1 508 (20) (50) N-20b A1 152 (6) (73.6) DR-3 A2L 178 (7) (70.8) ARM-20b A2L 178 (7) (56) L-20a (R-444B) A2L 356 (14) (55.3) DR-93 A1 152 (6) (64.5) R-290 A3 203 (8) (25.8) ID: N/A for R-22, 1.65 mm (0.065 ) for alternative refrigerants 24 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

25 COP Impact on COP 5.0 B A T3* T3 Hot Extreme R-22/mineral oil L-20a (R-444B) DR-3 N-20b ARM-20b R-290/POE DR Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

26 Cooling Capacity, kw Impact on Capacity 8 B A T3* T3 Hot Extreme R-22/mineral oil L-20a (R-444B) DR-3 N-20b ARM-20b R-290/POE DR Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

27 T comp T comp, R-22, C Impact on Compressor Discharge Temperature (T comp ) B A T3* T3 Hot Extreme L-20a (R-444B) DR-3 N-20b ARM-20b R-290/POE DR Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

28 Performance Relative to Baseline at Different Test Conditions

29 COP AHRI A: 35 C Outdoor and 27 C Indoor 110% R-290/POE 105% 100% R-22 w/ 95% L-20a (R-444B) 90% ARM-20b N-20b 85% DR-3 DR-93 80% 80% 85% 90% 95% 100% 105% Cooling Capacity 29 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

30 COP ISO T3: 46 C Outdoor and 29 C Indoor 110% 105% 100% 95% R-290/POE L-20a (R-444B) R-22 w/ mineral oil 90% N-20b 85% DR-3 DR-93 ARM-20b 80% 80% 85% 90% 95% 100% 105% Cooling Capacity 30 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

31 COP Hot: 52 C Outdoor and 29 C Indoor 110% 105% 100% 95% 90% 85% N-20b DR-3 R-290/POE DR-93 L-20a (R-444B) ARM-20b R-22 w/ mineral oil 80% 80% 85% 90% 95% 100% 105% Cooling Capacity 31 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

32 COP Extreme: 55 C Outdoor and 29 C Indoor 110% 105% 100% 95% 90% 85% N-20b DR-3 R-290/POE DR-93 L-20a (R-444B) ARM-20b R-22 w/ mineral oil 80% 80% 85% 90% 95% 100% 105% Cooling Capacity 32 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

33 R-410A Mini-Split AC Unit Results

34 R-410A Unit Refrigerant R-410A (baseline) ASHRAE safety class Capillary Tube Length, mm (Inch) Charge mass kg (oz) A1 673 (26.5) (33) ARM-71a A2L 610 (24) (27) R-32 A2L 1016 (40) (25) DR-55 A2L 660 (26) (28.6) L-41 (R-447A) A2L 864 (34) (27.5) HPR-2A A2L 965 (38) (28.5) ID: 2 mm (0.079 ) for R-410A, 1.65 mm (0.065 ) for alternative refrigerants 34 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

35 COP Impact on COP B A T3* T3 Hot Extreme R-410A R-32 DR-55 L-41 (R-447A) ARM-71a HPR-2A 35 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

36 Cooling Capacity, kw Impact on Capacity 6 B A T3* T3 Hot Extreme R-410A R-32 DR-55 L-41 (R-447A) ARM-71a HPR-2A 36 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

37 T comp T comp, R-410A, C Impact on Compressor Discharge Temperature B A T3* T3 Hot Extreme R-32 DR-55 L-41 (R-447A) ARM-71a HPR-2A 37 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

38 Performance Relative to Baseline at Different Test Conditions

39 COP AHRI A: 35 C Outdoor and 27 C Indoor 110% 105% 100% HPR-2A DR-55 ARM-71a R-410A R-32 95% 90% L-41 (R- 447A) 80% 90% 100% 110% Cooling Capacity 39 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

40 COP ISO T3: 46 C Outdoor and 29 C Indoor 110% 105% 100% 95% L-41 (R- HPR-2A 447A) DR-55 ARM-71a R-410A R-32 90% 80% 90% 100% 110% Cooling Capacity 40 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

41 COP Hot: 52 C Outdoor and 29 C Indoor 110% 105% 100% HPR-2A L-41 (R- 447A) ARM-71a DR-55 R-410A R-32 95% 90% 80% 90% 100% 110% Cooling Capacity 41 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

42 COP Extreme: 55 C Outdoor and 29 C Indoor 110% 105% 100% L-41 (R- 447A) ARM-71a HPR-2A DR-55 R-410A R-32 95% 90% 80% 90% 100% 110% Cooling Capacity 42 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

43 Overall Conclusions (Mini-Split Units) The results are for soft optimized systems only; efficiency and capacity of the alternative refrigerants can be expected to improve through design modifications before introducing a new product to market. Multiple alternatives for R-22 performed well, and most R- 410A alternatives matched or exceeded the performance of R-410A. These may be considered as prime candidate lower GWP refrigerants for high-ambient-temperature environments. 43 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

44 R-22 Conclusions The A1 alternative refrigerants lagged in performance and require from 29 to 47% more refrigerant mass compared to R-22 baseline system charge. Some of the A2L refrigerants showed capacity within 5% and efficiency within approximately 10% of the baseline system at ambient temperature at or above 46 C, albeit with a slightly higher compressor discharge temperature. The A3 refrigerant (R-290) exhibited higher efficiency; however, it did not match the cooling capacity (8 to 10% lower). It also resulted in lower compressor discharge temperatures. 44 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

45 R-410 Conclusions R-32 showed better capacity and efficiency, but it resulted in higher compressor discharge temperatures. DR-55 had consistently higher COPs and matched the capacity at higher-ambient conditions. HPR-2A s efficiency exceeded the baseline at all ambient temperatures higher than 35 C. R-447A and ARM-71a had lower capacity, but R-447A had better COP at ambient temperatures higher than 46 C. 45 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

46 Packaged Rooftop Units

47 RTUs R-22 Unit SKM PACL-51095Y 380/415V, 3 Ph, 50 Hz Capacity* = 92.8 kbtu/h (27.2 kw) EER = N/A R-410A Unit PETRA PPH V, 3 Ph, 60 Hz Capacity* = 132 kbtu/h (~ kw) EER* = (COP ~ 3.12) *Gross capacity at ISO 5151 T1 (Indoor DBT 27 C, WBT 19 C) 47 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

48 R-22 Experiment Setup (RTU) 48 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

49 R-410A Experimental Setup (RTU) 49 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

50 T comp T comp, R-22, C Impact on Compressor Discharge Temperature (T comp ) 0 A T3 Hot R-444B ARM-20b R-454A 50 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

51 Performance Relative to R-22 at AHRI A Conditions (R-22 RTU) COP/COP R % 105% 100% 95% 90% 85% R-22 w/ POE R-444B ARM-20b R-454A 80% 90% 95% 100% 105% 110% Capacity/Capacity R Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

52 Performance Relative to R-22 at Hot Conditions (R-22 RTU) COP/COP R % 105% 100% 95% 90% 85% R-22 w/ POE R-444B ARM-20b R-454A 80% 90% 95% 100% 105% 110% Capacity/Capacity R Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

53 R-22 Conclusions (RTU) Test run using electronic expansion valve to simulate potential TXV retrofit All 3 refrigerants showed almost equal or higher cooling capacity (fixed air flow rate) R-444B benefited the most when tested under constant external static pressure conditions: at Hot test conditions the COP was 95% that of the baseline and the capacity was 102% that of the baseline Higher the ambient temperature, lower the relative COP Lower compressor discharge temperature 53 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

54 T comp T comp, R-410A, C Impact on Compressor Discharge Temperature (Tcomp) A T3 Hot Extreme L-41z DR-55 ARM-71a 54 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

55 COP Performance Relative to R-410A at AHRI A Conditions (RTU) 110% 105% 100% L-41z ARM-71a DR-55 95% 90% 90% 95% 100% 105% 110% Cooling Capacity 55 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

56 COP Performance Relative to R-410A at Extreme Conditions (RTU) 110% L-41z ARM-71a 105% DR % 95% 90% 90% 95% 100% 105% 110% Cooling Capacity 56 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

57 R-410 Conclusions (RTU) All 3 refrigerants showed higher efficiency at all conditions DR-55 matched the capacity at all conditions (fixed air flow rate) L-41z and ARM-71a had comparable capacity at Hot and Extreme conditions, but slightly lower capacity at A and T3 conditions Compressor discharge temperature was higher by 5 to 10 C 57 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

58 Future of Air Conditioning

59 Need to Look Forward A/C technologies and markets have seen: Substantial declines in product and lifecycle cooling costs in many A/C markets Higher sales volumes Higher energy efficiency Transition away from ozone-depleting substances (ODS) In the next decade, we expect: Rapid growth of A/C markets in developing nations with hot, humid climates Increased frequency of extreme heat waves due to global warming Continued efficiency improvements Transition to low-global Warming Potential (GWP) refrigerants Advancement of non-vapor-compression A/C technologies 59 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

60 Refrigerant Cost Vs. Life Cycle A/C Cost India RAC estimate based on Shah et al. (2016) estimates for equipment cost breakdown, markups, and average operating cost for a 7 year lifetime assuming 67.3 Rs to USD conversion. U.S. CAC estimate uses latest CAC TSD estimates of manufacture product cost (Table 5-14), markups (Table 6.8.1), and national average annual and discounted lifetime operating cost (Table 8.4.1) for a 3-ton split-system CAC including blower for a >20 year lifetime. 60 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

61 Emerging R&D Solutions Advanced Vapor-Compression Systems A/C technologies that significantly lower refrigerant GWP and energy consumption while maintaining cost-competitiveness; for example: Low-GWP refrigerants (e.g., natural refrigerants and synthetic olefins) Climate-specific designs Emerging Non-Vapor-Compression (NVC) Systems A/C technologies that do not rely on refrigerant-based vaporcompression and can provide energy savings (with highvolume cost similar to today s); for example: Solid-state & caloric (thermoelectric, magnetocaloric) Electro-mechanical (evaporative, thermoelastic) Thermally driven (absorption) 61 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

62 Elements of sustainable, low-emissions A/C systems Developing a Cohesive Solution Set for Indirect and Direct A/C emissions 62 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

63 Pathway to the Future International Collaboration Promptly adopt an ambitious global HFC phase-down amendment to the Montreal Protocol Engage & support the industry through collaborative efforts Domestic Policy / Regulation Implement domestic HFC phase-down regulations Develop robust refrigerant management schemes Implement and strengthen minimum efficiency standards Provide example policies, strategies, and support Emerging Technology R&D Support R&D for low- GWP and NVC technologies Support sustainable building design, renewable integration, and waste heat recycling Collaborate with developing nations to support adoption of new technologies 63 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

64 The Future of Air Conditioning for Buildings Published July 2016 by EERE BTO. ngs/downloads/future-airconditioning-buildingsreport Prepared by Navigant Consulting, Inc. with support from Oak Ridge National Laboratory (ORNL) and review by DOE, EPA and White House OEQ 64 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

65 Acknowledgment Extraordinary team at ORNL: Dr. Som Shrestha, Dr. Bo Shen, Dr. Ahmed Elatar, Mr. Randy Linkous Extraordinary team at Navigant Consulting: Mr. William Goetzler, Mr. Matthew Guernsey, Theo Kassuga Dr. Patrick Phelan (USA) and Dr. Suely Carvalho (Brazil) for their support and chairmanship of the panel of international experts. The U.S. Department of Energy BTO, and specifically Mr. Antonio Bouza for his support. Panel of International Experts ORNL BERG/BTRIC 65 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

66 Questions? Omar Abdelaziz, Abdelaziz et al., 2015, Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners, ORNL/TM-2015/536, available online at: 66 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

67 References IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. Miller (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA; section : Direct Global Warming Potentials. Available: IPCC, Myhre, G., D. Shindell, F.-M. Bréon, W. Collins, J. Fuglestvedt, J. Huang, D. Koch, J.-F. Lamarque, D. Lee, B. Mendoza, T. Nakajima, A. Robock, G. Stephens, T. Takemura and H. Zhang, 2013: Anthropogenic and Natural Radiative Forcing. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex, and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Available: 67 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries

68 Commercial Residential Low-GWP Product Availability Products using low-gwp, 4 th generation refrigerants are already available in some applications. Offer comparable or improved efficiency relative to today s typical equipment Currently available in four key product categories, including ductless split systems, by far the largest market segment globally (>60% of the market) Flammability and cost are key limiting factors Equipment Status Approved for use in U.S. U.S. SNAP Application Submitted Best GWP Detail Example 2012 Global Annual Sales (US$B) Room and portable <10 R-290; R -32 $3.4 Ducted split & single-package <700 Multiple candidates $3.3 Ductless split system <10 R-32; R-290 $48.5 Packaged terminal <700 R-32 $0.2 Packaged rooftop unit <700 Multiple candidates $4.6 Ductless (VRF/VRV) <700 R-32 $10.7 Scroll / recip. chiller <700 DR-55 (R-452B) Screw chiller <10 R-513A; R-1234ze(E) Centrifugal chiller <10 R-1233zd(E), R-1234ze(E) Source for market size: Approximate 2012 global sales data (includes equipment using all refrigerants) from BSRIA; U.S approval status from EPA website Commercially available in some global markets; Product under development; Tested in Lab 68 Alternatives for Air-Conditioning Industry in High Ambient Temperature Countries $8.3 (all chillers)