Where Refrigerants are Heading in NZ

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Where Refrigerants are
Heading in NZ?
Don J. Cleland and Richard J Love
Centre for Postharvest and Refrigeration Research
Massey University, Palmerston North, New Zealand
NZ Coldstorage Association Conference
Wellington, 17 August 2014
Overview
•
•
•
•
•
•
•
•
Context
The Perfect Refrigerant
Alternative Refrigerants
Alternative Technologies
Future Options
Lessons from the Past
ETS Impacts & Challenges
Conclusions & Recommendations
2
Introduction
•
•
Enhanced work Health & Safety compliance after
Pike River disaster and Christchurch earthquake
Environmental pressures
–
–
–
–
•
growing population
urban migration
resource depletion
standard of living expectations
Ozone depletion
–
–
–
–
–
–
caused by man-made chemicals including refrigerants
response exemplary
Montreal Protocol (MP)
on track to solve
phaseout of CFCs & HCFCs
effectively no new HCFC imports from 2015
3
Global Warming
• Evidence not certain
– is there GW?
– anthropogenic or natural effect?
– magnitude & timeline of impacts
• Scientific proof growing
• Potential impact huge
• Precautionary principle
adopted
– minimise and mitigate
4
Proof that the World is getting warmer
5
After a new research project with substantially increased budget the
result was essentially the same:
Kyoto Protocol
• Basket of 6 gases
–
–
–
–
–
–
CO2: fuel use
CH4: decomposition
N2O: agriculture
SF4: electrical switchgear
Perfluorocarbons:fire extinguishers & foams
HFCs: refrigerants & foams
• Does not cover MP gases
• Stablise emissions for 2008-2012 to 108% of 1990 levels
• GWP quantifies impact relative to CO2
7
Refrigeration & GW
• Direct emissions (≈ 1%)
– many refrigerants have high GWP
– e.g. HFC-134a has GWP of 1300
• Indirect due to energy use (≈6%)
– ≈0.6 kg CO2/kWh
• ETS
– 2 tonnes per unit in transition
– ETS of initially $25/tonne CO2
equivalent
– actual 2014 CO2 unit price of about
$2-5/tonne CO2
4
Emissions Equivalent Mt CO2
– refrigeration about 15% of electricity
demand
– electricity generation about 40% of
emissions
Domestic Refrigeration
Split Stationary Air
Conditionerss
Packaged Air Conditioners
3.5
3
Refrigerated Air Conditioners
2.5
Light Vehicle Air
Conditioning
Heavy Vehicle Air
Conditioning
Transport Refrigeration
2
1.5
Commercial Refrigeration
1
Commercial Air Conditioning
Foam
0.5
Fire Fighting Equipment
0
1990
8
1995
2000
2005
Aerosol
2010
2015
Refrigerants
Source: Danfoss
9
The Perfect Refrigerant
Prosperity (Economic)
People (Society)
- low cost
- high performance
- energy efficient
- safe
- stable
- wide material
compatibility
- low cost equipment
- low GWP
- safe
o non-flammable
o low pressure
o distinctive colour or
smell
- low toxicity
- energy efficient
- low cost equipment
Planet (Environment)
- zero ODP
- low GWP
- energy efficient
- low toxicity
- unstable (short
atmospheric life)
10
Refrigerant Families
Criteria
HCFCs
HFCs
HFOs
NRs
low/medium
medium
high
low
medium
medium
medium
high
Capacity
good
good
good
very good
Energy Efficiency
good
good
good
very good
ODP
yes
no
no
no
GWP (ETS)
high
high
low
very low
good
generally
good
good except
flammability
often
significant
risks
traditional
synthetic
synthetic
wide
Refrigerant Cost
(no levy)
System Cost
Safety (e.g. flammability,
toxicity, high pressure)
Oil Compatibility
11
Refrigerant
Formula
ODP
GWP
Oil Compatibility
0.0
0.0
0.0
0.0
0.0
0.0
0.0
3260
POE
75
0.0
1530
POE
35
High glide
0.0
1730
POE
40
High P
0.0
1960
M,AB,POE
45
Medium glide
0.0
2620
M,POE
60
Medium glide
CCl3F
CCl2F2
115 (51%), 22 (49%)
1.0
1.0
0.23
R22
R123
CH Cl F2
C2H Cl2F3
0.055
0.02
R32
R125
R134a
R143a
R152a
R245ca
R507
CH2F2
C2HF5
C2H2F4
C2H3F3
C2H4F2
C3H3F5
125 (44%), 134a (4%), 143a
(52%)
32 (23%), 125 (25%), 134a
(52%)
32 (50%), 125 (50%)
125 (46.6%), 134a (50%),
600 (3.4%)
125 (65.1%), 134a (31.5%),
600a (3.4%)
125 (50%), 143a (50%)
R1234yf
R1234ze
C3H2F4
C3H2F4
R218
C3F8
R170 - ethane
R290 - propane
R600a - isobutane
R717 - ammonia
R718 - water
C2H6
C3H8
C4H10
NH3
H2O
3300
POE
HFOs
POE
0.0
4
0.0
6
POE
Perfluorocarbons (PFs)
0.0
7000
Natural Refrigerants (NRs)
0.0
~5
M,AB,POE
0.0
~5
M,AB,POE
0.0
~5
M,AB,POE
0.0
<1
M
0.0
<1
R744 – CO2
CO2
0.0
R1270 - propylene
C3H6
0.0
R407C
R410A
R417A
R422D
Other Weaknesses
CFCs
4000
8500
5590
HCFCs
1700
93
HFCs
650
2800
1300
3800
140
560
R11
R12
R502
R404A
Levy
($/kg)
M
M
M
-
MP phaseout
MP phaseout
MP phaseout
M,AB
M,AB,POE
-
MP phaseout
MP phaseout
POE
POE,PAG
0.0
1
M
15
64
30
87
3
13
A2L
A2L
A2L
76
0.1
0.1
A2L, high cost
High cost
161
Long EAL
-
A3
A3
A3
B2L, low P, no copper
0oC limit, very low P
-
12 Low critical temp., high P
-
A3
ASHRAE Classification
Source: Reindl, 2011
13
Oils
14
Alternative Technologies
• Possibilities
–
–
–
–
–
–
–
acoustic
magnetic
thermo-electric (Peltier)
vortex tube
Brayton (air) cycle
Stirling cycle
absorption/adsorption
• Issues
– low efficiency
– low capacity
– high cost
• Niche applications e.g. Peltier for low noise
• Absorption if low cost heat
15
Improvements to
Reverse Rankin Cycle
•
•
•
•
•
expanders
multi-staging
heat transfer enhancement
variable speed technology
transcritical if gas cooling
matches process need
• cascades & secondary
refrigerants
16
Future Options
• ETS cost for most HFCs incentivizes
– reduction in leakage
– reduction in charge
– replacement with low GWP refrigerants
• Likely replacements have concerns
– performance (e.g. CO2)
– cost (e.g. HFOs)
– safety (e.g. HCs or HFOs)
• Flammability harder to avoid
17
Total Impact
TEWI (kg CO2) = direct refrigerant + indirect energy use
= GWP M [x n + (1 - α)] + E n β
LCCP (kg CO2) = TEWI + emissions due to manufacture
where
•
•
•
•
M = refrigerant charge (kg)
x = leakage rate (% per year)
n = equipment life (years)
E = energy consumption (kWh/year)
α = recovery factor (%)
β = electricity emissions factor (kg CO2/kWh)
Leakage & energy use seldom known accurately when refrigerant chosen &
investing
5-20% leakage pa (Cowan et al., 2011)
ETS converts environmental consideration into an economic one
Net loss if lower GWP refrigerant has very poor energy efficiency
18
Leakage
19
Alternative Performance
Refrigerant
HFC-404A
Alternative
3260
150
Charge (kg)
5
5
Leakage (% pa)
5
5
Energy Use (kWh pa)
25,000
+5%
TEWI (kg CO2)
388,855
394,388 (+1.4%)
656+37,500 = 38,156
30+39375 = 39,405(+3.3%)
GWP
ETS + Energy Cost ($)
o
o
o
o
15 year equipment life
90% refrigerant recovery
Electricity emission factor of 1 kg CO2/kWh
Electricity cost of $0.1/kWh
• If charge & leakage low, then GWP less important than efficiency
20
Relative Performance
• Ammonia, HCs, CO2 (low temp.) often more efficient
than HFCs (up to 10%) e.g.
– theoretically R290 1-2% poorer than R22
– drop-in field trial gave 5-10% improvement for farm milk cooling
(Cleland et al., 2009)
• HFO1234yf close match to R134a
• R32 & HFOs similar to R22 and R410A (high temp.
applications)
• R404A (low temp.)
– R410A promising but moderate GWP & equipment constraints
21
Cascades & Secondaries
•
•
•
•
•
Use refrigerants in optimal temp. range
Minimise & isolate charges of high GWP, flammable or toxic refrigerants
“Safe” refrigerants or secondaries in populated areas e.g. glycol
Energy penalty due to extra temp. difference and pumps
CO2 likely low stage & secondary
–
–
–
–
–
•
safe & low cost
efficient
low pumping power/pressure drop
low mass & volumetric flows
equipment availability & cost improving
High stage refrigerants situation specific
22
Relative Performance
System
Capital
Energy
Annual
Frozen Warehouse Complex;19,000 m2
Cost
Energy
Factor
(Edwards, 2006, 2008)
Life Cycle
Costs (20 yr)
DX R404A
$2,500,000
1.2
$1,00,000
$25,250,000
DX Ammonia
$3,063,000
1
$813,000
$22,063,000
Pumped Ammonia
$3,125,000
0.8
$650,000
$17,625,000
Secondary CO2
$3,625,000
0.87
$706,000
$19,875,000
Secondary T40
$3,750,000
+$50,000
$756,000
$20,875,000
Cascade CO2
$3,375,000
0.84
$688,000
$19,250,000
Edwards (2006)
23
Lessons from the Past
•
•
Concern that CFC alternatives less efficient & lower capacity
Reality was little difference if wise choices
– better heat transfer properties
– better oils
•
•
•
•
•
•
•
•
•
•
Initially many drop-ins but stabilized to manageable number of
replacements
Retrofits became routine
Initially little thermodynamic & equipment performance data but rapidly
rectified
High glide refrigerants more challenging
Material incompatibilities seldom acute
High pressure R410A a concern!
Extra costs passed onto customers
Familiarity bred contempt after initial fear of the unknown
Similar experience likely now but driven by cost rather than legislation
Scandinavia since 2007
– low GWP refrigerants for large systems
– proliferation of low charge systems
24
Past Future Predictions
Application
Automotive Air Cond.
Domestic appliances
Retail food - low temp
- med. temp
Chillers - centrifugal
- reciprocating
Insulating foams
Industrial refrigeration
Sector
Domestic Refrigerator
Commercial Equipment
Medium Temperature
Commercial Equipment
Low Temperature
Large Commercial &
Industrial
Mobile Air Conditioning or
Refrigeration
Air Conditioning
Original
R12
R12
R502
R12, R22,
R502
R11
R12
R12
R11, R12
R22, R502, NH3
Compressor Type
Sealed Unit
Sealed Unit
Accessible Hermetic
Reciprocating Open Drive
Sealed Unit
Accessible Hermetic
Reciprocating Open Drive
Reciprocating Open Drive
Centrifugal/Screw
Reciprocating Open Drive
Reciprocating Open Drive
Centrifugal/Screw
Accessible semi-Hermetic
Replacements
foreseen in 1990
Replacements
foreseen in 1994
HFC-134a, blends
HFC-134a, blends
HCFC-22, HFC-125
HCFC-22,HFC-134a HFC125, blends
HCFC-123
HFC-134a, blends
HFC-134a,
HCFC-22, blends
HCFC-123,HCFC-22
HCFC-22, NH3
HFC-134a
HFC-134a, R290
HFC-507, HFC-404A
HFC-134a, HFC-507
HFC-404A
Blends
HFC-134a
HFC-134a
Source: Lommers, 2003
various
HFC-507, HFC-404A, NH3
Refrigerant
R134a, R401A, R409a, R413a
R134a, R22, R401A1, R404A, R407A, R409A, R413A, R507
R134a, R22, R401A2, R404A, R407C, R413A, R507
R134a, R22, R401A2, R404A, R407C, R409A2, R413A, R507
R22, R402A, R402B, R403A, R404A, R407B, R408A, R410A, R507
R22, R402B, R403A, R404A, R407B, R408A, R410A, R507
R22, R402A, R402B, R403A, R404A, R407B, R408A, R410A, R507
R22, R134a, R401A, R401B, R402A, R403A,R404A, R407B4, R407C4,
R408A, R409A,R410A, R413A, R507, R717
R134a, R123, possibly R1243 , R22, R407A4, R401A4, R717
R22, R134a, R401C, R402A, R403A,R404A, R407C, R408A, R409A,
R409B,R416A, R507, possibly R22
R22, R134a, R401A, R409A, R410A,R413A
R134a, R123, R22, R410A
R22, R123, R134a, R401B, R404A, R407C, R409B, R410A, R507
25
Pathways – Past & Future
CFCs
HCFCs
HFCs
HFOs/NRs
Comments
11
123
134a
245ca
1234yf
717
low charge
134a
1234yf
600a
low charge
717
744
HFO?
low stage of cascade
blends?
12
502
Pre-1990
404A
507
22
404A
407C
507
410A
417A
422D
Pre-2005
Pre-2012
HFO?
blends?
717
744 if water heating needed
744 low stage of cascade
170+290
low charge
HFC-32
low charge
170+290
low charge
744 low stage of cascade
HFO?
blends?
Post-2012
26
ETS Impacts & Challenges
• Cost will be passed onto customers
• Potential for increased margins
• Incentives for
–
–
–
–
–
good practice (reducing charge & leakage)
life cycle costing & impacts assessment
innovative design & service practice
early replacement of older less efficient plant
development of skills to work with flammable refrigerants
• Disadvantages
– higher refrigerant inventory costs
– higher risk of refrigerant theft
– higher business risk if ignorant about issues & alternative
refrigerants
– incentives to delay R22 replacement
– uncertainty about availability and cost of HFOs in the short term
– poorer customer relations due to poor understanding of ETS
– greater number of refrigerants in short term
27
Barriers
• Surveys by Burhenne & Chasserot (2011)
and Colbourne (2011)
– knowledge levels
– technology availability
– safety concerns and related psychological
factors
– too restrictive regulations and standards
28
Conclusions
The ETS on refrigerants will
– increase costs
– provide incentives for best practice
– enhance commercial opportunities for well-informed
and proactive customers & service providers
– increase consideration of NR options
– provide the chemical industry motivation to develop
efficient & safe synthetic alternatives
– provide an opportunity for the refrigeration industry
to lift its performance
– not be a significant threat
29
Recommendations
•
•
•
•
•
•
•
•
Reduce refrigerant charges in new systems
Increase tightness of existing systems
Expect flammable refrigerants so understand the risks
Keep informed about environmental issues & refrigerant
options & performance
Use a life cycle costing approach so long term focus
Shift to lower GWP refrigerants when significant system
changes are needed
Carefully plan and schedule replacement of existing large
R22 systems (short term delay may be astute)
Try to use NRs if safety issues can be addressed costeffectively
30
Back to the Future?
©2008 Risto Ciconkov
31
Questions
d.cleland@massey.ac.nz
References
1.
2.
3.
4.
5.
6.
7.
8.
9.
Burhenne, N., Chasserot, M. (2011) Natural refrigerants in the HVAC&R industry – a
study of global market and policy trends. Proceedings International Congress of
Refrigeration, Prague, Czech Republic, August 2011, paper 147.
Calm, J.M., Hourahan, G.C. (2011) Physical, safety and environmental data for current
and alternative refrigerants. Proceedings International Congress of Refrigeration,
Prague, Czech Republic, August 2011, paper 915.
Cleland, D.J., Keedwell, R.W., Adams, S.R. (2009) Use of hydrocarbons as drop-in
replacements for HCFC-22 in on-farm milk cooling equipment, International Journal of
Refrigeration 32: 1403-1411.
Colbourne, D. (2011) Barriers to the uptake of low GWP alternatives to HCFC
refrigerants in developing countries. Proceedings International Congress of
Refrigeration, Prague, Czech Republic, August 2011, paper 628.
Cowan, D., Lundqvist, P., Maidment, G., Chaer, I. (2011) Refrigerant leakage and
constainment – overview of the activities of the IIR working party on mitigation of direct
emissions of greenhouse gases in refrigeration. Proceedings International Congress of
Refrigeration, Prague, Czech Republic, August 2011, paper 856.
DCCEE (2012), Australian National Greenhouse Accounts: National Inventory Report
2010,
Department of Climate Change and Energy Efficiency, Canberra, http://www.climatech
ange.gov.au/emissions
Edwards, B.F. (2006) CO2 refrigeration. Presented at IIR-IRHACE 2006 Conference,
Auckland, NZ, 16-18 February, 2006.
Edwards, B.F. (2008) Personal communication; Realcold Ltd, New Zealand
Lommers, C.A. (2003). Air-Conditioning and Refrigeration Refrigerant Selection33
Guide
- 2003, AIRAH, Melbourne.
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