XV EUROPEAN CONFERENCE MILANO 7th-8th JUNE 2013 CSG
Latest Technology in Refrigeration and Air Conditioning Under the Auspices of the PRESIDENCY OF THE COUNCIL OF MINISTERS
An evaluation of low GWP refrigerants in A/C and in Refrigeration
An evaluation of low GWP refrigerants in A/C and in Refrigeration
15th EUROPEAN CONFERENCETECHNOLOGICAL INNOVATIONS
IN REFRIGERATION AND IN AIR CONDITIONINGMilano June 7th 2013
Bachir Bella
Contents
• Low GWP Refrigerants Candidates
• Drop-in tests w/ R32 & HFOs in Comfort
• Drop-in tests w/ HFOs in refrigeration
• Conclusion
Markets
RefrigerantsNH3
R134aR404A/507
R290
R134a R404A
R404A/507R407AR134a
CO2
R404A/507R407A/FR134aR290
R410AR407C
R410AR407C
ComfortResidential
ComfortComm.
Emerson – Global Player Offering Products Across Entire Landscape
0%
20%
40%
60%
80%
100%
120%
2005 2010 2015 2020 2025 2030 2035 2040 2045 2050 2055
NAPDevel'd Countries
F-Gas Review (Draft)
NAPA5 Countries
HFC Phase-Down Proposals Also On Table: North American Proposal (NAP) And F-Gas Proposal
F-Gas Proposal Reserved Right To Amend Based On Any International Agreement – Allowance For NAP Adoption
• Baseline Updated 2008-2010
• Excluded HFOs From Basket For Phase-down
• Fewer Steps In Phase-Down, But End Year And Target Held Same
NAP Update 4/2013
NA ProposalNon A5 Countries
F-Gas Proposal
NA ProposalA5 Countries
Refrigerants Choice was a Trade offs between Capacity, WP & Performance
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Capacity Vs. R22
GWP
R143aR125
R134a
R32
R152a
R290
R600a
R407C
R410A
R404AR407A
R407F
1400 < GWP < 4000
Today HFCs
R32 R134a R125 R143aR410A 50 0 50 0R407A 20 40 40 0R407C 23 52 25 0R407F 30 40 30 0R404A 0 4 44 52
Base for HFCs Blends
ODP = 0Class A1 ( Non toxic, Non flammable)
Next Refrigerants will be a Trade offs between Performance, GWP and Safety
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
0 500 1000 1500 2000 2500 3000 3500 4000 4500
Capacity Vs. R22
GWP
R143a
R125
R134a
R744
R32
R152a
R290
R600a
R1234..R407C
R410A
R404A
R407A
R407FR404A Like
R410A like
R404A like
R134a Like
Base for HFOs
R1234ze R1234yf R152a R32
L41a 12 15 0 73L41b 27 0 0 73DR5 0 27.5 0 72.5L40 30 20 10 40DR7 0 64 0 36L20 35 0 20 45
Source : Thomas E. Watson “AHRI low-GWP alternative refrigerant Evaluation program” Convegno Aicarr Vicenza, Nov. 2012
Flammable
Non Flammable
Flammability is evaluated by ‘Chance of Flame occurring’ and ‘Effect of Flame occurring’•Effect of Flame occurring -> Burning Velocity, Heat of Combustion
Burning Velocity – Basis For 2 & 2L Classification
Reference: Low GWP Refrigerant Options For Unitary AC & Heat Pumps – Mark Spatz, ASHRAE Jan 2011
Low Energy Release
High Energy Release
Unstable Flame, Low Pressure
Rise
Stable Flame, High Pressure
Rise
0
10
20
30
40
50
60
0 5 10 15 20 25 30 35 40 45 50
Burning Velocity, cm/s
Hea
t of C
ombu
stio
n, M
J/kg
R152a
Ammonia
R32
HFO-1234yf
R134a
methane
propane
butane
ASHRAE Class 3
ASHRAE Class 2
Class 2L
gasoline
New A2L Class –
R32, R1234yf, R1234ze
- IEC 60335-40 and ISO 5149 Are Key
Standards Related To Flammability
- Modifications Required For Both Ducted
and Non Ducted Applications
- Equations For Maximum Charge Being
Developed Relating To Room Size, Unit
Location & Height, Ventilation, and
Refrigerant LFL
Timely A2L Standards Crucial For Commercialization / Meet Phase Down
A3
A2
A2L
A1
R152a
ASHRAE 34 Class A (Non-Toxic)
Propane R290
Isobutane R600a
R410A, R134a, R407C
Highly
Flammable
Flammable
Mildly
Flammable
Non-
Flammable
Need To Accelerate A2L Standards Development Globally
A Commercial Scroll designed for R410A tested R32
Compressor Results Possible System Effect
Higher capacity (Avg. +7%) Smaller displacement
~ 2/3% higher efficiency Higher system full load efficiency
Same to slightly lower efficiency at low Cond. Temp.
Expected similar ESEER
-20 -15 -10 -5 0 5 10 15 20 -20 -15 -10 -5 0 5 10 15 20
25 5 % 5 % 5 % 5 % 5 % 4 % 2 % 1 % 0 % 0 % 0 % 0 %
30 5 % 5 % 6 % 5 % 5 % 5 % 5 % 1 % 1 % 0 % 0 % -1 % -1 % -1 %
35 6 % 6 % 6 % 6 % 6 % 5 % 5 % 1 % 1 % 0 % 0 % 0 % -1 % -2 %
40 6 % 7 % 7 % 6 % 6 % 6 % 1 % 1 % 1 % 1 % 0 % -1 %
45 7 % 7 % 8 % 7 % 7 % 7 % 2 % 2 % 2 % 1 % 0 % -1 %
50 8 % 9 % 9 % 9 % 9 % 8 % 2 % 3 % 3 % 3 % 2 % 0 %
55 10 % 10 % 10 % 10 % 10 % 4 % 4 % 4 % 4 % 2 %
60 13 % 13 % 13 % 12 % 5 % 6 % 6 % 4 %
62 14 % 14 % 14 % 7 % 6 % 5 %
Evaporating Temperature (°C) Evaporating Temperature (°C)
Co
de
ns
ing
Te
mp
era
ture
(°C
)
Cooling Capacity Variation COP
25 m3/h Scroll compressor
7, 62
0, 65
0
10
20
30
40
50
60
70
-40 -30 -20 -10 0 10 20 30
ESEER
HP MTwarmer
HP MTaverageHP MT
colder
Defrost
DHW
R410A
R32
warm climates
Discharge temperature and the operating envelops with R32 and R410A
20
40
60
80
100
120
140
5/50 � C -5/50 � C -10/45 � C
Dis
char
ge
tem
pe
ratu
re (�C
)
R32R410A
R32 Map limited for HP, reversible systems and Chillers in warm climates
R32 Discharge temp. rises up to 35 K limiting heavily the operating envelope
to extend the EnvelopeVapor or Liquid Injection could be used
Cooling Capacity increases up to 26% COP Improves up to 14% Discharge Temperature drops in the range 11 to 16 K
This temperature drop will extend the envelope by 5 / 8 K Reversible Chiller and HP needs VI or Liquid injection to widen the envelope
LI enlarges the application envelope with negative impact on the COP
20 m3/h Scroll compressor w/ vapor injection
Evap.Temp.
Cond.Temp.
Cooling Cap. COPDischarge
Temp.
(°C) (°C) (%) (%) (K)
-20 25 17% 10% -16
-15 35 20% 12% -11
-10 45 26% 14% -12
-5 50 24% 13% -11
Variation with Vapor Injection
100
110
120
130
140
150
40 45 50 55
Dis
char
ge
Tem
per
atu
re (�
C)
Condensing Temperature (� C)
R32 Discharge temperature w/ Vapor Injection
+ 5K Condensing
Reliabilit Limit
Tevap = -10°C
NO VIwith VI
Drop in Tests w/ LGWP Refrigerants on Residential Comfort Scroll
70%
80%
90%
100%
110%
Vari
ation
vs.
R41
0A
R32 DR5 L41b
Cooling Capacity COPc
SH = 11K, SC 8K5°C / 50°C
70%
80%
90%
100%
110%
-6.7/35 °C -6.7/50 °C -6.7/35 -6.7/50
Vari
ation
vs.
R41
0A
R32 DR5 L41b
Heating Capacity COPh
• R32 capacity increases less towards commercial scroll, and COP is lower vs. R410A• DR5 performances are close to R410A• L41b is 20% less capacity
(*) Blends Performance are referred to the Dew Point at standard conditions
HFOs should better perform when referred to the mid-point instead of dew point
5 m3/h Scroll compressor
A drop-in experiment has been carried out on a R404A compressor with DR7 and L40
12
• DR7 Capacity close to R404A • L40 Lower capacity in the range 79% to 95%.• Either L40 or DR7 offer better efficiency at high condensing
temperature
Med. Temp.Low Temp. Med. Temp.Low Temp.
0.92
1
0.94
0.975
0.95
1.04
0.79
0.85
0.82
0.86
0.83
0.95
0.7
0.75
0.8
0.85
0.9
0.95
1
1.05
1.1
-31.7/21.1 °C -31.7/40.6 °C -17.8/21.1 °C -17.8/37.8 °C -6.7/21.1 °C -6.7/48.9 °C
DR7, L40 Relative Capacity vs. R404A (Dew Point Based)Actual compressor Tests - 6Hp Scroll
11 K Superheat, 0 k SubcoolDR-7 L-40
1.04
1.11
1.01
1.07
1.00
1.1
1.03
1.1
1.02
1.07
1.00
1.13
0.7
0.75
0.8
0.85
0.9
0.95
1
1.05
1.1
1.15
1.2
-31.7/21.1 °C -31.7/40.6 °C -17.8/21.1 °C -17.8/37.8 °C -6.7/21.1 °C -6.7/48.9 °C
DR7, L40 Relative COP vs. R404A (Dew Point Based)Actual compressor Tests - 6Hp Scroll
11 K Superheat, 0 k SubcoolDR-7 L-40
17 m3/h Scroll compressor
Drop-in System tests Carried out on walk-in system with DR7 and L40
13
• Walk-In System• Box Temperature -23°C
– Standard AHRI 1250
DR7 and L40 Exhibit Relatively Better Performance vs. theoretical due to Mid-Point vs. Dew-Point
96%
98%
100%
102%
104%
106%
108%
110%
112%
85% 90% 95% 100% 105% 110%
% R
404
COP
% R404 Capacity
L-40
DR-7
• DR5 gives more cooling capacity and a COP from 2 to 6% higher vs. R404A. • L40 has only 3% less capacity and its COP is 3 to 4% higher compared to R404A.
Performance Summary
• Potential w/ these candidates with optimized scroll compressor• The blends should perform better in a real system as the reference
is the mid point temperature
Application Reference AlternativeCoolingCapacity
COPDischarge
Temp.
R32 +4 / 13 % -2 / +6% Up to +40 K
L41
DR5
R32 +2 / +6 % -7 / 0% Up to +40 K
L41 -20 / -18% -8 / -2%
DR5 -5 / -2% -5 / 0%
L40 -21 / -5% 0 / +13% Higher
DR7 -8 / +4% 0 /+11% Higher
R410A
Residential A/C & HP
Refrigeration R404A
Commercial A/C & HP
Conclusions
Important To Reduce GWP Without Sacrificing Efficiency Due To Increasing Efficiency Standards
R32 Shows Limitation due to Higher Discharge Temperature While R32 based Blends have Less Limitation
HFO Blends Overall Performance Potentially Comparable To today HFCs But Cost And Availability Still Unknown
Both Compressors and Systems Can Be further Optimized For R32 and HFO Blends
Acceleration Of A2L Standards Development For New Equipment Is Critical to Reach Phase Down Targets
16
GRAZIE !
Questions?
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