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ASHRAE Research Program
On Related Topics
Opening Remarks
Session on:
Relevant Research Programs and Initiatives for Finding Alternatives
Alternative Refrigerants for Air-Conditioning Industry in High-Ambient Temperature Countries; Bridging
Environment, Standards and Research
Intercontinental Hotel (Festival City)
Dubai, UAE (10-11 Sept, 2013)
Walid Chakroun
Kuwait University
Where Are We Now
 HFCs are greenhouse gases and the value of GWP quantifies this effect
on global warming-- In some applications, the “indirect” effect of
producing energy is much greater than the GWP effect of the
refrigerant itself.
 Total equivalent warming impact (TEWI)--include both direct and
indirect impacts of refrigeration systems--Life cycle climate
Performance LCCP
 Under the Kyoto Protocol, no specific mandates for reductions or
phase out of the HFCs -European Union enacting regulations on HFCs
--F-Gas Legislation-Some countries went even beyond by proposing an
amendment to the Montreal Protocol to start phasing down HFC.
 These developments led to renewed and increased interest in natural
refrigerants and the development of new low-GWP options.
Present Facts
 The process of switching to Low GWP is moving at different speeds
around the world—Challenges for High Ambient Temperature countries
 Refrigerants selection and their operating systems still not based on a
holistic analysis of multiple criteria- energy efficiency, system
performance, potential impact on community safety, risk to personal
safety, cost, and minimization of direct and indirect environmental
impacts.
 Some HFOs are available in limited quantities, Not yet fully tested in all
applications. Some HFOs and lower-GWP HFCs have mild flammability
and cost is high.
 No ideal refrigerant yet. Natural refrigerants, the HFCs, the unsaturated
HFCs (also known as HFOs), and possibly blends will continued to be
used.
Challenges- High Ambient Temperature
(TEAP, 2012)
 High ambient temperatures lead to high condensing temperatures and
pressures.—Consequences COPs drops 20%- 25%.
 Constrains in high discharge temperature and pressure lead to the choice of
“medium pressure” refrigerant such as HFC-134a or HFC-1234yf for single stage
systems.
 Lack of low-GWP refrigerants with a large refrigeration capacity in order to
replace R-404A or HCFC-22 in single stage refrigeration systems.
Issues for Considerations
 Concern about the high GWP of some HFCs ---calling to reduce it.
Research to extend lower-GWP HFCs into new applications and to
develop new refrigerants that minimize environmental impacts and
safety concerns
 Issues with natural refrigerants: flammability, toxicity, high pressures,
in some cases, lower operating efficiencies, their behavior in operating
systems
 Balancing the safety, energy efficiency, cost, and environmental impact
for refrigerants using a consistent and comprehensive methodology
across all refrigerants and system types using benchmarks like TEWI or
LCCP
 Advancing the design of equipment that facilitate reduced refrigerant
emissions--Methodologies and practices to minimize or prevent
refrigerant loss during installation, operation, maintenance,
decommissioning and end of life disposal.
ASHRAE Research Program
On Related Topics
Session on:
Relevant Research Programs and Initiatives for Finding Alternatives
Alternative Refrigerants for Air-Conditioning Industry in High-Ambient Temperature Countries; Bridging
Environment, Standards and Research
Intercontinental Hotel (Festival City)
Dubai, UAE (10-11 Sept, 2013)
Walid Chakroun
Kuwait University
Contents
Efforts in the Field of Refrigeration
and Energy Efficiency
 ASHRAE Position Documents
 ASHRAE Research Projects
 Conferences and Design Guides
 Research Recommendations
ASHRAE Position Document
ASHRAE position documents are
approved by the Board of Directors and
express the views of the Society.
ASHRAE Position Document
 Ammonia as a Refrigerant
o ASHRAE considers that the continued use of ammonia is necessary for food preservation
and air conditioning.
o ASHRAE will:

 Continue research on ammonia topics such as handling, application, operation, control of
emissions and new technology.

 Maintain and develop standards and guidelines for practical and safe application of
ammonia in refrigeration systems.

 Advise governments and code officials with information regarding ammonia.
ASHRAE Position Document
 Natural Refrigerants
o ASHARE believes that “natural refrigerants” offers the potential to improve the
environmental performance of refrigeration systems.
o Because of its alignment with sustainability initiatives, ASHRAE supports
research, assessment, and strategic growth in the use of natural refrigerants.
o In light of the current global scenario, ASHRAE’s response to the demand for
environmental sustainability is to promote the development of systems which
use natural refrigerants safely, economically and efficiently.
ASHRAE Position Document
 Refrigerants and their Responsible Use
o Environmental concerns have caused ozone-depleting potential, global warming potential,
energy efficiency, and life-cycle climate performance to become important factors.
o
This often results in conflicts between choices: if a lower global warming potential (GWP)
refrigerant is less efficient than the fluid which it replaces, any direct global warming
benefit may be offset by increased energy consumption.
o ASHRAE’s position is that the selection of refrigerants and their operating systems be
based on a holistic analysis of multiple criteria.
ASHRAE Research Projects
 1327-RP Flow Regime and Pressure Drop Determination for Two-Phase
Ammonia Upward Flow in Various Riser Sizes
The objective of this research project is to determine the minimum vapor velocity required
to sustain vertical upward flow of liquid ammonia when transported by vapor ammonia in
the same pipe.
 1410-RP Effect of System Chemicals toward the Breakdown of Lubricants
and Refrigerants
The objectives of this research project are to conduct a literature search to identify
additional, more recent classes of fundamental chemicals that are likely to produce
significant interactions with the HFC/POE systems.
ASHRAE Research Projects
 1467-RP Balancing Latent Heat Load between Display Cases and Store
Comfort Cooling
The overall objective of this project is to provide a comprehensive assessment of the
potential for energy savings in supermarkets by optimized design and operation of the
combined HVAC and refrigeration systems.

1507-RP Binary Refrigerant Flame Boundary Concentrations
To ensure the validity of flammability safety classifications issued by SSPC34, standard
reference data is needed. Tools such as the proposed flammability property database will
allow for the development of blends that are properly investigated and classified to meet
demanding future needs.
ASHRAE Research Projects
 1535-RP A Heat Transfer and Friction Factor Correlation for Low Air-Side
Reynolds Number Applications of Compact Heat Exchangers
The objective of this research is to develop airside heat transfer and pressure drop
correlations for high performance compact heat exchangers under low air velocity
conditions.
 1564-RP Measurement of Oil Retention in the Microchannel Heat
Exchangers
This work will provide essential design data for state-of-art microchannel heat exchangers
by showing how much oil is held up, causing the heat transfer performance degradation
and additional pressure drops at various operating conditions.
ASHRAE Research Projects
 1584-RP
Assessment of Alternative Approaches to Predicting the
Burning Velocity of a Refrigerant
The objective of this project is to identify technically acceptable parameters that may be
used to accurately predict or estimate the burning velocity of refrigerants.
 1602-RP Thermal-Fluid Behavior of Mixed Refrigerants for Cryogenic
Applications
Mixed refrigerants are widely used to extend vapor compression type cycles to lower
temperatures. The thermodynamic and thermal-fluid behavior of these mixtures is
critically important to the industrial designer.
ASHRAE Research Projects
 1646-RP Measurements of Thermal Conductivity of Pipe Insulations at
Below Ambient Temperatures and in Wet Condensing Conditions with
Moisture Ingress
Prior to the work performed under the ASHRAE funded research project RP-1356, there
was no procedure for determining the thermal performance of pipe insulation systems
below ambient conditions. Moisture ingress into piping can lead to degraded service life
and lower performance of the systems, corrosion of the pipes, and mold growth on the
surfaces inside the buildings.
Conferences and Design Guides
 ASHRAE Research Project 1634 - Design Guide for
Sustainable Refrigeration Facilities and Systems
oASHRAE research project co-sponsored and co-funded by UNEP.
oThe Guide will serve as an important new international reference with valuable
recommendations, methods and examples.
oSubjects include refrigeration system and facility design, cooling loads,
equipment choices and performance modeling—all within the framework of
sustainability and life-cycle design.
oThe Guide will have a global perspective, recognizing the rapid growth of the
“food chain” in developing and recently developed countries,
where refrigerant and system choices are viewed with a “clean sheet”, offering a
timely opportunity to provide valuable guidance.
Conferences and Design Guides
 ASHRAE Special Project 137 -Refrigeration
Commissioning Design Guide
o The Refrigeration Commissioning Guide will provide user-friendly, how-to
guidance for commissioning of refrigeration systems in commercial and
industrial facilities.
o The intended audience of this Guide includes but is not limited to system
owners, architects, design engineers, contractors, facility managers, and
maintenance service providers, as well providers of commissioning services.
o Goal to be available by end of 2013
Conferences and Design Guides
 Refrigeration Management Plan (RMP)
o
ASHRAE has established an exploratory committee evaluate the interest and
commitment of the various refrigerant industry stakeholders in a
voluntary refrigerant management program aimed at minimizing the emissions
and overall environmental impact of refrigerants used in the HVAC&R industry.
Conferences and Design Guides
 ASHRAE/NIST Refrigerants Conference: Moving
Towards Sustainability
o 4th jointly sponsored conference held last October. Refrigeration Committee will
consider future Refrigerants Conferences in the series as well.
o Conference focused on low GWP alternatives stemming from international
concerns about the adverse environmental impacts of refrigerants with high
ODP and GWP. These alternatives include new generations of unsaturated
fluorochemicals, with continued examination of “natural” refrigerants.
Conferences and Design Guides
 ASHRAE, IIR, EPA, Ammonia institute are collaborating with the National
institute of standards in a conference on refrigeration Technology
o the Conference focuses on low GWP alternatives stemming from international
concerns about the adverse environmental impacts of refrigerants with high
ODP and GWP.
o These alternatives include new generations of unsaturated fluorochemicals, with
continued examination of “natural” refrigerants.
Conferences and Design Guides
 ASHRAE, AHRI, QEERI, REHVA, CIBSE, IAPMO
( International Association of Plumbing and
Mechanical Officials) are collaborating in the FIRST
International Conference on Energy & INDOOR
ENVIRONEMENT FOR HIGH AMBIENT TEMPERATURE
COUNTRIES
 Feb. 24-26, 2014 to look at Energy , IAQ, and Refrigeration issues in high
temperature countries.
Map of Refrigerant Change
Research Recommendations
 balancing the safety, energy efficiency, cost, and environmental impact for
refrigerants using a consistent and comprehensive methodology across all
refrigerants and system types using benchmarks like LCCP, life cycle
assessment (LCA) or TEWI
 advancing the design and development of refrigeration and air conditioning
equipment that facilitate reduced refrigerant emissions
 developing methodologies and practices to minimize or prevent refrigerant loss
during installation, operation, maintenance, and decommissioning of
refrigeration systems
 developing new refrigerants that minimize environmental impacts and safety
concerns