[PPT] - Alternative Refrigerant Evaluation for High- A Ambient-Temperature PowerPoint Presentation

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Alternative Refrigerant Evaluation for High- A bi t T t Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners Conditioners Technical Forum on R h P j t f Research Projects for Alternative Refrigerants in High Ambient Countries High Ambient Countries 31October 2015 Conrad Hotel Dubai UAE

ORNL is managed by UT-Battelle for the US Department of Energy

Conrad Hotel - Dubai, UAE

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Presented by

Dr. Omar Abdelaziz, ORNL

Group Leader, Building E i t R h Equipment Research, Energy and Transportation Science Division and Dr Suely Machado

Dr. Suely Machado

Carvalho, IPEN (BRAZIL); Senior Researcher C h i I t ti l E t Co-chair, International Expert Panel on Alternative Refrigerant Evaluation for HAT

ORNL is managed by UT-Battelle for the US Department of Energy

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Program Objective

Evaluate the performance of alternative lower

Gl b l W i P t ti l (L GWP) f i t Global Warming Potential (Low-GWP) refrigerants for mini-split air conditioning under high ambient temperatures. temperatures.

Help evaluate the viability of using alternative lower-

GWP refrigerants in said markets to avoid the costly g y transition from HCFC to HFC and then from HFC to lower-GWP refrigerants

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Panel of International Experts

Dr. Suely M. Carvalho (IPEN, Brazil) and

Co-Chairs

Dr. Patrick Phelan (Department of Energy, USA)

Panel Members

Dr. Radhey Agarwal (India)
Dr. Karim Amrane (USA)
Mr. Maher Moussa

(Kingdom of Saudi Arabia)

Dr. Enio Bandarra (Brazil)
Dr. J. Bhambure (India)

Mr Ayman El Talouny (UNEP) Arabia)

Mr. Ole Nielsen (UNIDO)
Mr. Tetsuji Okada (Japan)
Mr. Ayman El-Talouny (UNEP)
Dr. Tingxun Li (China)
Dr Samuel Yana Motta (Peru)
Dr. Alaa Olama (Egypt)
Dr. Alessandro Giuliano

P (It l )

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Dr. Samuel Yana Motta (Peru)

Peru (Italy)

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Panel Tasks

Provide independent technical input for the ORNL

t d study

Recommend alternative refrigerants to be tested
Review and comment on appropriate test

procedures

Assess results
Review the interim working paper and the final

report

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Panel Overall Timeline

Mid April: Meeting in Bangkok Early March: First Conference Call Mid April: Meeting in Bangkok Mid March: First Conference Call d p eet g a g o Mid June: Review Interim Report d p eet g a g o Mid June: Review Interim Report Early July: Publish Interim Report Early July: Publish Interim Report Early August: Meeting in Yokohama Early September: Review Final Report Early August: Meeting in Yokohama Mid October: Final Report Published

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Meeting of the Parties

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Final Report Available

ORNL/TM-2015/536
http://info.ornl.gov/sit

es/publications/Files/ P b59157 pdf Pub59157.pdf

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Evaluation Program Program

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Why ORNL

User facilities and flagship modeling

capabilities p

Decades of experience in alternative refrigerant

evaluation programs: p g

– CFC phaseout strategy – Global Warming Impacts of Ozone-Safe Refrigerants and HVAC&R T h l i HVAC&R Technologies – Global total equivalent warming impact (TEWI) analysis of HFC refrigerants and emerging technologies g g g g – Development of Low-GWP Refrigerant Solutions for Commercial Refrigeration Systems using a Life Cycle Climate Performance Design Tool

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Climate Performance Design Tool

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Industry Support

Equipment supplier: Carrier (Larry Burns)

– Designed for high-ambient performance up to 55°C – Rated capacity at ISO T1 = 5.28 kW (18 kBtu/h) – Rated coefficient of performance (COP): 2.78 for the R-22 baseline unit and 3 37 for the R-410A baseline unit baseline unit and 3.37 for the R 410A baseline unit

Refrigerant supplier:

– Honeywell (Ankit Sethi) Honeywell (Ankit Sethi) – Chemours (previously Dupont) (Barbara Minor) – Mexichem (Sean Cunningham) – Arkema (Laurent Abbas)

AHRI (Xudong Wang)

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( g g)

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R-22 Alternative Refrigerants

Refrigerant Manufacturer ASHRAE safety GWPa AR4 AR5 Refrigerant Manufacturer safety class AR4 AR5 R-22 – A1 1,810 1,760 N-20Bb Honeywell A1 988 904 DR-3b Chemours A2L 148 146 ARM-20Bb Arkema A2L 251 251 ARM 20B Arkema A2L 251 251 L-20Ab Honeywell A2L 295 295 DR-93b Chemours A1 1,258 1,153 R 290 A3 3 3 R-290 – A3 3 3

a Sources: IPCC AR4, 2007; IPCC AR5, 2013. b GWP values for refrigerant blends not included in IPCC reports are

calc lated as a eighted a erage sing man fact rer s pplied compositions

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calculated as a weighted average using manufacturer-supplied compositions.

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R-410A Alternative Refrigerants

R f i t M f t ASHRAE f t GWPa Refrigerant Manufacturer safety class AR4 AR5 R-410A – A1 2088 1924 ARM-71Ab Arkema A2L 460 461 R-32 Daikin A2L 675 677 DR-55b Chemours A2L 698 676 L-41b Honeywell A2L 583 572 HPR 2Ab Mexichem A2L 600 593

a Sources: IPCC AR4, 2007; IPCC AR5, 2013. b GWP values for refrigerant blends not included in IPCC reports are

calc lated as a eighted a erage sing man fact rer s pplied compositions

HPR-2Ab Mexichem A2L 600 593

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calculated as a weighted average using manufacturer-supplied compositions.

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Test Conditions

Test diti

Outdoor Indoor

Dry bulb Dry bulb Wet bulb Relative condition Dry-bulb temp. Dry-bulb temp. Wet-bulb temp. Relative humidity °C (°F) °C (°F) °C (°F) % ( ) ( ) ( ) AHRI B 27.8 (82.0) 26.7 (80.0) 19.4 (67.0) 50.9 AHRI A 35.0 (95.0) 26.7 (80.0) 19.4 (67.0) 50.9 T3* 46 (114.8) 26.7 (80.0) 19 (66.2) 50.9 T3 46 (114.8) 29 (84.2) 19 (66.2) 39.0 Hot 52 (125.6) 29 (84.2) 19 (66.2) 39.0 Extreme 55 (131.0) 29 (84.2) 19 (66.2) 39.0

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Facilities

Multi-Zone Environmental Chambers: “Outdoor” chamber is

6.1×4.6 m; the 8.5 m square “indoor” chamber can be divided into up to four spaces controlled at different divided into up to four spaces controlled at different conditions to represent separate zones. Dry-bulb temperature is controlled at −23 to 55°C (−10 to 131°F) and relative humidity at 30 to 90%

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relative humidity at 30 to 90%.

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Instrumentation: R-22 system

Custom-built air enthalpy tunnel complying with AHRI

Standard 210/240 and ANSI/ASHRAE Standard 37: air flow 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)

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

Barometric pressure sensors: ±0.6 hPa/mb

Power meters: ±0.2% reading

All instrumentation was calibrated either by ORNL metrology or by a third-

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All instrumentation was calibrated either by ORNL metrology or by a third party calibration laboratory before the experimental campaign began.

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R-22 Experiment Setup

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R-22 Experiment Setup

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R-22 Experiment Uncertainty

Air-side uncertainty:

– Capacity = ±2.3% – COP = ±2.4%

Refrigerant-side uncertainty:

– Capacity = ±0.7% COP <±0 8% – COP = <±0.8%

Energy balance between air-side and

refrigerant side measurements: refrigerant-side measurements:

– AHRI A: −2.3% to 2.89% – AHRI B: −1.99% to 2.37%

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AHRI B: 1.99% to 2.37%

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Instrumentation: R-410A system

Code tester complying with AHRI Standard 210/240 and

ANSI/ASHRAE Standard 37 ANSI/ASHRAE Standard 37

Coriolis mass flow meter: CMF25 with ±0.5% error

Pressure sensors: ±0 08% BSL

Pressure sensors: ±0.08% BSL
RTD: ±0.15°C (0.27°F) @ 0°C

W t b lb 0 15°C (0 27°F) @ 0°C

Wet-bulb sensors: ±0.15°C (0.27°F) @ 0°C
Barometric pressure sensors: ±0.6 hPa/mb
Power meters: ±0.2% reading

All instrumentation was calibrated either by ORNL metrology or by a third-

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y gy y party calibration laboratory before the experimental campaign began.

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R-410A Experimental Setup

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R-410A Experimental Setup

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R-410A Experiment Uncertainty

Air-side uncertainty:

– Capacity: ±1.6% – COP: ±1.5%

Refrigerant-side uncertainty:

– Capacity: ±0.65% COP ±0 81% – COP: ±0.81%

Energy balance between air-side and

refrigerant side measurements: refrigerant-side measurements:

– AHRI A: −3.6% to 0.05% – AHRI B: −3.97% to 0.05%

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AHRI B: 3.97% to 0.05%

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Optimization of Alternative Refrigerants

Optimization

sequence: sequence:

– Optimize charge – Find best capillary tube 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

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extreme conditions

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R-22 Unit Results

Baseline: R-22 w ith mineral oil

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R-22 Unit

Refrigerant Manufacturer ASHRAE safety Charge mass kg (oz) g y class kg (oz) R-22 (baseline) – A1 1.417 (50) N-20B Honeywell A1 2.087 (73.6) DR-3 Chemours A2L 2.007 (70.8) ARM 20B A k A2L 1 588 (56) ARM-20B Arkema A2L 1.588 (56) L-20A (R-444B) Honeywell A2L 1.568 (55.3) DR 93 Chemours A1 1 828 (64 5) DR-93 Chemours A1 1.828 (64.5) R-290 – A3 0.731 (25.8)

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Impact on COP

B A T3* T3 Hot Extreme 4.0 5.0 2.0 3.0 COP 0.0 1.0 R‐22/mineral oil L‐20A (R‐444B) DR‐3 N‐20B ARM‐20B R‐290/POE DR 93

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DR‐93

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Impact on Capacity

B A T3* T3 Hot Extreme 6 8 ty, kW 2 4 g Capaci 2 Cooling R‐22/mineral oil L‐20A (R‐444B) DR‐3 N‐20B ARM‐20B R‐290/POE DR 93

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DR‐93

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Overall Evaporator Temperature Glide

B A T3* T3 Hot Extreme 5 Glide ator, °C ‐5 erature Evapora ‐10 Temp at the R‐22/mineral oil L‐20A (R‐444B) DR‐3 N‐20B ARM‐20B R‐290/POE DR 93

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DR‐93

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Impact on Compressor Discharge Temperature (Tcomp) Temperature (Tcomp)

B A T3* T3 Hot Extreme 5 10

line , °C

‐5 Tcomp, basel 20 ‐15 ‐10 Tcomp – T ‐20 T L‐20A (R‐444B) DR‐3 N‐20B ARM 20B R 290/POE DR 93

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ARM‐20B R‐290/POE DR‐93

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Performance Relative to Baseline at AHRI A Conditions 35°C (95°F) Outdoor and 27°C ( ) (80°F) Indoor

110% R‐290/POE 105% 110% L‐20A (R‐ 95% 100% COP 444B) DR 3 N‐20B ARM‐20B DR 93 85% 90% DR‐3 DR‐93 80% 80% 85% 90% 95% 100% 105%

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Cooling Capacity

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Performance Relative to Baseline at ISO T3 Conditions 46°C (114.8°F) Outdoor and 29°C ( ) (84.2°F) Indoor

110% R‐290/POE 105% 110% L‐20A (R‐ 95% 100% COP 444B) DR 3 N‐20B ARM‐20B DR‐93 85% 90% C DR‐3 80% 85% 80% 85% 90% 95% 100% 105%

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Cooling Capacity

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Performance Relative to Baseline at Hot Conditions 52°C (125.6°F) Outdoor and 29°C ( ) (84.2°F) Indoor

110% R‐290/POE 105% 110% L‐20A (R‐ 444B) N 20B 95% 100% COP DR‐3 N‐20B ARM‐20B DR‐93 85% 90% 80% 80% 85% 90% 95% 100% 105%

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Cooling Capacity

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Performance Relative to Baseline at Extreme Conditions 55°C (131°F) Outdoor ( ) and 29°C (84.2°F) Indoor

110% R‐290/POE 105% 110% L‐20A (R‐ 444B) N‐20B 95% 100% COP DR‐3 N 20B ARM‐20B DR‐93 85% 90% 80% 80% 85% 90% 95% 100% 105%

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Cooling Capacity

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Performance of R-444B at Different Test Conditions Conditions

110% 100% 105% 3* T3 H t Extreme 90% 95% COP B A T3* Hot 85% 90% 80% 80% 85% 90% 95% 100% 105% Cooling Capacity

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Cooling Capacity

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Performance of ARM-20A at Different Test Conditions Test Conditions

110% 100% 105% B A T3* 90% 95% COP T3* T3 Hot 85% 90% Hot Extreme 80% 80% 85% 90% 95% 100% 105% Cooling Capacity

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Cooling Capacity

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Performance of R-290/POE at Different Test Conditions Test Conditions

110% 100% 105% B A T3* 90% 95% COP T3* T3 Hot 85% 90% Hot Extreme 80% 80% 85% 90% 95% 100% 105% Cooling Capacity

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Cooling Capacity

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R-410A Unit

R f i t M f t ASHRAE f t Charge mass Refrigerant Manufacturer safety class Charge mass kg (oz) R-410A A1 ( ) R 410A (baseline) – A1 0.936 (33) ARM-71A Arkema A2L 0.765 (27) R-32 Daikin A2L 0.709 (25) DR-55 Chemours A2L 0.811 (28.6) L-41 (R-447A) Honeywell A2L 0.780 (27.5) HPR-2A Mexichem A2L 0.808 (28.5)

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Impact on COP

B A T3* T3 Hot Extreme 3 4 5 1 2 3 COP 1 R 410A R 32 DR 55 R‐410A R‐32 DR‐55 L‐41 (R‐447A) ARM‐71a HPR‐2A

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Impact on Capacity

B A T3* T3 Hot Extreme 5 6 ty, kW 3 4 Capacit 1 2 Cooling R‐410A R‐32 DR‐55 L 41 (R 447A) ARM 71a HPR 2A

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L‐41 (R‐447A) ARM‐71a HPR‐2A

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Impact on Compressor Discharge Temperature Temperature

25 15 20

seline, °C

10 15 Tcomp, bas 5 Tcomp – B A T3* T3 Hot Extreme R 32 DR 55 L 41 (R 447A) ARM 71a HPR 2A

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R‐32 DR‐55 L‐41 (R‐447A) ARM‐71a HPR‐2A

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Performance Relative to Baseline at AHRI A Conditions 35°C (95°F) Outdoor and 27°C ( ) (80°F) Indoor

110% R‐32 DR‐55 105% ARM‐71a HPR‐2A 100% COP L‐41 (R‐ 447A) 95% 90% 80% 90% 100% 110% Cooling Capacity

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Cooling Capacity

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Performance Relative to Baseline at ISO T3 Conditions 46°C (114.8°F) Outdoor and 29°C ( ) (84.2°F) Indoor

110% L 41 (R HPR‐2A 105% R‐32 DR‐55 L‐41 (R‐ 447A) ARM 71a 100% COP ARM‐71a 95% 90% 80% 90% 100% 110%

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Cooling Capacity

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Performance Relative to Baseline at Hot Conditions 52°C (125.6°F) Outdoor and 29°C ( ) (84.2°F) Indoor

110% R‐32 DR‐55 L‐41 (R‐ HPR‐2A 105% 447A) ARM‐71a 100% COP 95% 90% 80% 90% 100% 110% Cooling Capacity

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Cooling Capacity

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Performance Relative to Baseline at Extreme Conditions 55°C (131°F) Outdoor ( ) and 29°C (84.2°F) Indoor

110% R‐32 DR‐55 L‐41 (R‐ 447A) HPR‐2A 105% DR 55 ) ARM‐71a 100% COP 95% 90% 80% 90% 100% 110% Cooling Capacity

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Cooling Capacity

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Performance of R-32 at Different Test Conditions Conditions

110% A T3* Hot Extreme 105% B T3 100% COP 95% 90% 80% 90% 100% 110% Cooling Capacity

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Cooling Capacity

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Performance of DR-55 at Different Test Conditions Conditions

110% B A T3* Hot 105% B T3 Extreme 100% COP 95% 90% 80% 90% 100% 110% Cooling Capacity

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Cooling Capacity

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Performance of HPR-2A at Different Test Conditions Conditions

110% T3* T3 Hot Extreme 105% A T3 T3 100% COP B 95% 90% 80% 90% 100% 110% Cooling Capacity

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Cooling Capacity

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R-22 Conclusions

The A1 alternative refrigerants lagged in

f performance.

Some of the A2L refrigerants showed capacity

within 5% and efficiency within approximately 10% within 5% and efficiency within approximately 10%

f the baseline system at ambient temperature at or

above 46°C, albeit with a slightly higher compressor , g y g p discharge temperature.

The A3 refrigerant (R-290) exhibited higher

g ( ) g efficiency; however, it did not match the cooling

capacity. It also resulted in lower compressor

discharge temperatures

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discharge temperatures.

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R-410 Conclusions

R-32 showed better capacity and efficiency, but it

lt d i hi h di h resulted in higher compressor discharge temperatures. DR 55 had consistently higher COPs and matched

DR-55 had consistently higher COPs and matched

the capacity at higher-ambient conditions.

HPR 2A’s performance exceeded the baseline at all
HPR-2As performance exceeded the baseline at all

ambient temperatures higher than 35°C.

R 447A and ARM 71a had lower capacity but
R-447A and ARM-71a had lower capacity, but

R-447A had better COP at ambient temperatures higher than 46°C.

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Overall Conclusions (1)

Under all testing conditions, the performance of the

it d d d th td t t units degraded as the outdoor temperature increased. The obtained results are for soft optimized systems

The obtained results are for soft-optimized systems
nly; the efficiency and capacity of the alternative

refrigerants would be expected to improve through g p p g design modifications before a new product was introduced to market.

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Overall Conclusions (2)

Viable replacements exist for both R-22 and R-410A

t hi h bi t t t at high ambient temperatures.

Multiple alternatives for R-22 performed well, and

most R 410A alternatives matched or exceeded the most R-410A alternatives matched or exceeded the performance of R-410A. These may be considered as prime candidate lower-GWP refrigerants for p g high-ambient-temperature environments.

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Acknow ledgment

Extraordinary team at ORNL: Dr. Som Shrestha, Mr.

R d Li k Randy Linkous

Extraordinary team at Navigant Consulting: Mr.

William Goetzler Mr Matthew Guernsey Theo William Goetzler, Mr. Matthew Guernsey, Theo Kassuga

ORNL BERG/BTRIC
ORNL BERG/BTRIC
BTO support
Panel of International Experts

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Questions?

Omar Abdelaziz, abdelazizoa@ornl.gov

Abdelaziz et al., 2015, “Alternative Refrigerant Evaluation for High-Ambient-Temperature Evaluation for High Ambient Temperature Environments: R-22 and R-410A Alternatives for Mini- Split Air Conditioners”, ORNL/TM-2015/536, available

nline at:
nline at:

http://info.ornl.gov/sites/publications/Files/ Pub59157.pdf

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Pub59157.pdf

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References

IPCC, 2007: Climate Change 2007: The Physical Science Basis. Contribution of

Working Group I to the Fourth Assessment Report of the Intergovernmental g p p g 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 2.10.2: Direct Global Warming Potentials. Available: g https://www.ipcc.ch/publications_and_data/ar4/wg1/en/contents.html

IPCC, 2013. 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: https://www.ipcc.ch/pdf/assessment- report/ar5/wg1/WG1AR5_Chapter08_FINAL.pdf

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