Transcript Next Generation Water-Cooled Screw Chiller 75

India-US HFC workshop: February 18, New Delhi
WELCOME
By - Alex Pachai &
Kishor Patil
Technical Options for Commercial Refrigeration /
Transport Refrigeration / Large Chillers
GWP-driven policy pressure on HFCs ,Potential transition options &
challenges , Expected transition timeline and viability
THE ACCEPTABLE LEVEL OF GWP
WILL DEPEND ON EQUIPMENT TYPE,
APPLICATION, AND RECOVERY
“High” and “Low” GWP are relative terms and dependant on:

Application (mobile or stationary)

Average leak rate from the equipment

Recovery rate at the end of life
Result:
Different acceptable
levels of GWP
95% of global HFC use is currently between 700 and 4000 GWP
TEAP Proposed (May 2010) to classify GWPs by considering “Use
Patterns”
GWP
Classification
GWP<30
Ultra-low-GWP
GWP < 100
Very low-GWP
GWP < 300
Low-GWP
GWP < 1000
Moderate-GWP
GWP < 3000
High-GWP
GWP < 10,000
Very High GWP
GWP < 10,000
Ultra-High GWP
150 GWP
300 – 800 GWP
THE ROLE OF SAFETY CODES
ON REFRIGERANT OPTIONS
Equipment manufactures will only consider options
that will result in safe and affordable application.
 ASHRAE Standard 34: Adoption of the “2L” designation for
refrigerants with low flammability in 2010.
 Equipment Room Safety and electrical codes (ASHRAE
Standard 15, UL1995, etc.) must now be modified to ensure
safe use.
 Example: Recent EPA ruling allowing propane and isobutane
in residential refrigerators and freezers:
 Maximum charge amount
 Specific applications
 Prescribed safety code compliance
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D
Johnson Controls
Result:
The process of
adapting safety codes
will pace the adoption
of many flammable
and natural
refrigerant options.
This will require
industry and
government
cooperation.
Next Generation Low GWP Refrigerants:
Low GWP Man-Made Refrigerants:
Natural Refrigerants:
(NH3, CO2, Hydrocarbons, etc.)
HFO-1234yf:
Properties and characteristics have not changed:
•Flammability
•Toxicity
•High Working Pressure
•
Leading candidate to replace R-134a in mobile/
automotive applications
•
Low GWP (4), no Toxicity, slightly flammable.
•
May eventually have application in stationary HVAC
equipment but will require significant engineering and
safety code changes to make practical.
•Low Efficiency
Our ability to engineer solutions has improved since the early
1900s---Primarily Refrigeration and mobile AC applications.
HFO-1234ze:
•
Properties are good for Foam Blowing, not for HVAC
applications.
HFO/HFC/? Blends:
•
Better Performance at the cost of higher GWP
Significant technical and legislative challenges
New challenges For The Adoption Of Replacements
Safety:
 Toxicity
 Flammability
 Pressure
Sustainability:
 No ODP (What does this mean?)
 Balance of low GWP and energy efficiency.
95% of total Global Warming impact is from
energy use, while only 5% from GWP. We
must achieve balance for the environment.
Economic Cost and application fit:

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Adoption is dependant on affordability & fit
with application requirements
Johnson Controls
We cannot limit
options with a single
refrigerant policy.
Instead, we will need
to choose the best
long-term refrigerant
for each application.
When do “natural” refrigerants make sense in Chillers?
Natural Refrigerants remain excellent solutions in some very specific
chiller applications:

Ammonia

Hydrocarbons

Water (Li-Br Absorption and Vapor Compression)
Hydrocarbon
Energy Efficiency of resulting Systems must remain at HFC levels:

Industrial Refrigeration: Ammonia Used in 95% of Applications

Hydrocarbons have very high efficiency and very low GWP
System Cost and safety thresholds can be a Barrier to Adoption:

Remote locations, secondary loops and safety mitigation

Safety Measures or material compatibility can result in higher costs
Ammonia
When do HFO and HFCs make sense in Chillers?
Because of the requirements of safety, efficiency and cost, chemical
refrigerants will likely remain an option:

HFOs

HFCs

Blends of HFOs & HFCs
Equipment Size and application will dictate types used:

Large Commercial Air-Conditioning Applications

Commercial Roof-top Equipment

Refrigeration Applications in Populated Areas/Buildings
Most Economical Solution:

Technology and material compatibility already exist

Viable solution for conversion/retrofit of existing equipment
When do “flammable” refrigerants make sense in Chillers?
Several of the most efficient and lowest GWP refrigerants have some
level of flammability. Its use in chillers is dependant upon:

Charge Amount

Relative Level of Flammability (flame speed, energy of combustion)

Location of Equipment (Indoor/Outdoor)

Cost of required safety measures
HFO 1234yf?
Precedence exists for use in certain applications:

Industrial Refrigeration and Process Cooling
Will require Code and Standard Changes for Com/Res AC Duty:

Classification under ASHRAE Standard 34 (January 2010)

Safety Code Changes: ASHRAE Standard 15, UL 1995, etc.
Hydrocarbon
R-32?
Fluid Development Timeline
Blend of Existing Fluids
- Define fluid requirements
- Screen candidates via modeling
- Select preferred blend
- Stability/compatibility testing
- In house system testing
- Request regulatory approvals
(ASHRAE, SNAP)
- Customer/field testing
- Product literature/stewardship
- Secure source of supply
- Put supply chain in place
- Commercialize
0
Year
New Fluid
- Define fluid requirements
- Identify new compounds
- Synthesize small samples
1
- Acute toxicity screen and stability
- Make larger samples
2
- Continue acute toxicity testing,
flammability, compatibility
- Make larger samples, develop mfr route
3
4
- Continue subchronic toxicity testing, in house
system testing, environmental testing
- Customer/field testing
- Request regulatory approvals, registrations
(ASHRAE, SNAP, REACH)
- Review/upgrade building codes/standards
- Construction of pilot facility
5
- Put supply chain in place
- Product literature/stewardship
6-10
- Construction of first small commercial
facility and larger scale facilities
c
Timing is approximate: Failures such as poor toxicity results can restart the process
Equipment Development Timeline
0
Year
New equipment
- Discussions with producers on desired new fluid attributes
- On-going research into not-in-kind technologies (decades away)
1
2
- System modeling with early candidates for all applications
3
- Materials compatibility testing
- System testing (performance, reliability) when new fluid is available
4
- Solution selection (timing & choice varies by application)
- Review/upgrade building codes/standards
5
- Factory retooling & manufacturing machinery lead times
- Product development & commercialization roll-out
- Service training & infrastructure development
6-13
- Parts development & infrastructure creation
- Various product launches (some solutions may be available early)
H
Timing is approximate: Resource availability constrains quicker approach
Bottom Line
Innovation takes time
Developing refrigerants, testing toxicity, environmental impact evaluation etc. is
one side of the story which takes time and the options are decreasing (6 to 10
years).
Developing refrigeration systems, performance testing and selection of
components cannot always be done in parallel (additional 3 to 10 years)
Once the products are developed:
How do we gain acceptance in the market place?
Is the safety regulation in place?
Will the regulation be policed/enforced?
Is the education of service technicians in place?
Low hanging fruit:
Regular service and leak checks are essential to prevent direct emissions
(saving cost on refrigerants for top-up)
Regular service can help keeping up the efficiency of equipment saving power
India-US HFC workshop: February 18, New Delhi
Commercial/Transport/Industrial Refrigeration
Segmentation characteristics
Potential transition options & challenges
Transport and commercial refrigeration
Different applications drive potentially solutions:
• Stationary low temperature refrigeration – Ice Cream Freezer /
Cold Rooms / Vertical Deep Freezers ( Below –10 Deg C )
• Stationary medium temperature cooling – Cold Rooms / Beverage
Coolers / Display Cases ( Typically +2 - 0 Deg C )
• Transport refrigeration – Trailers / Trucks ( - 15 Deg C To +10
Deg C )
• Marine refrigeration ( -30 Deg C To + 2 Deg C )
• Bus/rail HVAC –( Comfort Cooling + 18 Deg C Air Temp )
What are the characteristics of each?
Stationary low temperature refrigeration
• Dedicated designs allow for customized solutions
• Today, HFC-404A delivers high capacity with good
energy efficiency
• Some potential fluorocarbon alternatives are emerging,
although no clear solutions identified yet
• Large charge size limits use of flammable refrigerants
• CO2 is a potentially viable replacement candidate
• Sub-critical operation with “cascade” design
• Maintain energy efficiency at higher cost
Environmental improvement with some cost add
Stationary medium temperature cooling
• Dedicated designs allow for customized solutions
• Today, HFC-134a delivers strong energy efficiency with
medium capacity
• Potential fluorocarbon alternatives are emerging,
although with mild flammability considerations
• Large charge size limits use of flammable refrigerants
• CO2 has more challenges at higher operating conditions
• Sub-critical operation with “cascade” design is not fully viable
• Important to identify efficient and safe fluorocarbon alternative
CO2 solution is less certain due to efficiency
Transport refrigeration – Trailers, Trucks
• Designs must cover broad operating range from low termp to
medium temp to heating applications
• Cascade systems (sub-critical operation) are not practical due to frequent
off-time which requires worse-case component designs
• Therefore, CO2 solution reduces efficiency even with cost add for most
geographies…efficiency maintenance possible in colder climates
• Today, HFC-404A delivers high capacity with good energy efficiency
• Some potential fluorocarbon alternatives are emerging, although no
clear solutions identified yet
• Flammable solutions challenging but could be possible in limited
applications, given lack of current viable solutions
Some possible alternatives although
none are the clear winner
Marine refrigeration
• Designs must cover broad operating range from low termp to
medium temp to heating applications
• Cascade systems (sub-critical operation) are not practical due to frequent
off-time which requires worse-case component designs
• Therefore, CO2 solution reduces efficiency even with cost add
• Today, HFC-404A delivers high capacity with good energy efficiency
• Some potential fluorocarbon alternatives are emerging, although no
clear solutions identified yet
• Flammable, toxic solutions are not viable given the inability to
adequately ventilate emissions within closed shipboard conditions
Efficient and safe alternatives are not yet known
Bus/rail HVAC
• Dedicated designs feasible due to narrower operating
range
• Today, HFC-407C delivers high capacity with good
energy efficiency
• Some potential fluorocarbon alternatives are emerging,
although no clear solutions identified yet
• CO2 and HFO-1234yf less feasible compared with auto
application since bus/rail requires higher cooling loads
compared to auto cooling demand
Efficient and safe alternatives are not yet known
Low GWP offerings do exist today
While the market has not fully moved to low GWP
solutions, offerings are being introduced where
conditions allow:
• Cascade CO2 stationary refrigeration systems are becoming
common in Europe and New Zealand
• Some CO2 transport refrigeration systems are being offered in
Europe trailer and marine applications
• Ammonia refrigeration systems have been and continue to be
prevalent in industrial refrigeration and food preservation
applications
Why the slow ramp-up?
Factors limiting more rapid adoption
• CO2 systems like cool climates
• Two-stage cascade systems can minimize negative impact on
efficiency in warmer climates, although with some cost increase
• Single stage systems can operate at sub-critical levels, with good
energy efficiency, although only in cooler climates
• Large charge ammonia systems have code limitations when operating in
high people density applications
• Transport refrigeration systems are primarily limited to single stage systems
given their significant off-times (as opposed to stationary refrigeration
systems), which limits their energy efficient use in warmer climates
• More complex systems requires a mature service infrastructure to maintain
optimum on-going operation
Yet, we have some success
to build from
Summary
• Commercial and transport refrigeration covers a wide
range of differing applications
• One solution does not fit all
• CO2 appears a viable solution in stationary, low temp
applications
• New solutions needed for full effective coverage of this
broad segment
Time needed to identify new
solutions for entire segment
Questions
&
Answers
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