STRATEGIC REFRIGERANT PLANNING
AN UPDATED, STEP-BY-STEP APPROACH TO
REFRIGERANT DECISION MAKING FOR CHILLER OWNERS
"It's not easy being green." - Kermit
the Frog
INTRODUCTION
With the current focus on correcting
past wrongs against the environment, Kermit's familiar lament
has a whole new meaning for building owners and managers. As we
wade through the seas of new and ever-changing regulation and
explore possible courses of action, one thing is certain: we must
begin now to plan for a CFC-free future.
Today, chlorine-based refrigerants
are the lifeblood of most air conditioning and refrigeration equipment.
Since 1932, these stable compounds have provided a safe, economical
medium for the transfer of heat. Air conditioning, once considered
a luxury, has become a vital part of modern society, touching
virtually every aspect of our daily lives.
Recent scientific studies have confirmed
that chlorofluorocarbon (CFC) refrigerants are a source of ozone-depleting
chlorine. Strict regulations mandate the phaseout of these refrigerants,
and in 1992 former President Bush announced that the U.S. would
unilaterally accelerate the phaseout of CFCs, terminating their
production at the end of 1995. Other legislation around the globe
- including the Montreal Protocol and the U.S. Clean Air Act -
calls for the phaseout of alternative refrigerants (hydrochlorofluorocarbons
or HCFCs). Not surprisingly, industry insiders and facilities
managers alike are predicting that the refrigerants needed to
service existing chillers will be both costly and in very short
supply.
While there are no simple solutions
to this complex challenge, there is a critical first step: Strategic
Refrigerant Planning. This important process will ensure that
your company's refrigerant-related decisions are firmly grounded
in the facts about your particular situation. Like all strategic
planning, Strategic Refrigerant Planning can be divided into three
basic steps: Analyze, Organize & Plan, and Execute.
STEP 1:
ANALYZE YOUR SITUATION
While the U.S. Environmental Protection
Agency (EPA) recommends assigning a Refrigerant Manager to handle
refrigerant planning, large companies may find that this demanding
job requires a team effort (although an individual may be designated
as a coordinator). A Refrigerant Management Team should include
representatives from throughout the company who deal with various
aspects of the refrigerant issue, including upper management,
facilities managers and technicians as well as legal, financial
and purchasing personnel. An Original Equipment Manufacturer (OEM)
should be assigned as a team member to supply up-to-date, in-depth
expertise on refrigerant choices, containment options, equipment
modification and so on.
Collect Data On Refrigerant Usage.
Data collection is the first step in the analysis phase. Start
by carefully reviewing your current refrigerant usage to determine
how much is used annually and where it goes. Most refrigerant
is "lost" through leaks, poor service practices and
at equip-ment disposal; of these, the biggest culprit is servicing.
It's useful to look at refrigerant losses on a percentage basis,
so you can concentrate on the biggest problem areas first. Data
should be recorded in a common Refrigerant Log (see example on
page 13), which should also detail the quantities and storage
locations of on-site refrigerant, including that which is in the
equipment. Make sure you are diligent in this effort: a quick
count of the refrigerant drums in storage is not enough; check
to be sure they are still filled with refrigerant!
In reviewing refrigerant usage, begin
with the equipment that's likely to have the greatest effect on
your operation. It is recommended that you start with equipment
that is 20 tons or larger. Log each unit's condition, age, refrigerant
type and leak record. Also note its physical location: is the
chiller easy to access for possible replacement, or is it obstructed
by pipes? Any refrigerant recovery/recycling equipment you have
should be included in the log as well. Document any unintentional
venting that has occurred, and the reasons why. Use a common Refrigerant
Log form for each unit to be sure you have all the information
needed to make fair comparisons later.
Gather Information On Standards
And Codes. While some team
members collect data, others should gather information on the
standards that relate to your operation. The American Society
of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE)
provides some excel-lent guidelines on properly installing, operating
and upgrading equipment. A relatively new safety code for mechanical
refrigeration equipment, ASHRAE 15-1994 will be reflected in the
new building codes drafted as alter-native refrigerants are adopted.
(Refer to Carrier publication 819-116 for an overview of ASHRAE
15.) ASHRAE Guideline 3 outlines several different approaches
for low-ering refrigeration equipment emissions. In addition,
several useful documents are available from the Air Conditioning
and Refrigeration Institute (ARI). ARI 700 is the current standard
required for adherence with the U.S. Clean Air Act. This will
soon be replaced by a new standard summarized in document IRG-1:
Handling and Reuse of Refrigerants in the United States (available
from ARI). ARI 740-1993 is a certification document for recovery
and recycling equipment, and is the guideline EPA will use when
certifying this equipment for manufacturers. ARI 700-1993 deals
with the quality of recycled refrigerant, specifying the purity
standards that refrigerant resellers must meet. ARI Guidelines
N and K include suggestions for storage containers for recovered
refrigerants, and guidelines for assigning colors to containers
for different types of refrigerants.
Of course, always consult local building
codes, many of which are already being updated to reflect ASHRAE
15- 1994 and address existing facilities. For detailed information
on refrigerant safety, the refrigerant manufacturers themselves
are excellent resources.
Review Containment Equipment And
Practices. Self-evaluation
is another important component of the Analysis phase. This should
include a complete review of the containment and recovery equipment
on site and your organization's practices for handling refrigerant.
According to federal law, company-owned recovery/containment devices
must be registered with EPA. ARI 740 is an excel-lent reference
on performance standards for this type of equipment.
EPA also mandates that any technician
who handles refrigerant must be certified. Now is the time to
be certain that you have a thorough training program in place,
supported by an up-to-date Code of Service Practice (see example
on page 11) which details the do's and don'ts of safe refrigerant
handling in terms that everyone can understand. The ultimate objective
is to upgrade your organization's service practices - particularly
critical in light of new refrigerants, equipment and safety concerns.
Finally, look at your chillers with
a critical eye. Are there existing recovery and/or containment
devices in use, and if so, are they permanently installed (piped
back into the unit) or portable? In your log, describe each unit's
location, noting whether potential spills would be vented up a
pipe or lost through a drain in the floor.
Then compare your findings to the latest
standards avail-able. For example, most low-pressure equipment
has a CFC-11 purge system for removing noncondensible gases, but
it typically does not vent to the outdoors. This is now required
under ASHRAE 15-1994. Note whether the unit has service valves.
Most older equipment does not, which means a technician can not
check fluid levels without affecting the refrigerant charge. And
don't overlook the condition of the mechanical room itself. It
is not unusual to find that equipment has been modified or upgraded
over the years, but the room itself has not been brought up to
date.
STEP 2:
ORGANIZE AND PLAN
Once the team has collected the critical
data about refrigerant usage, it's time organize that data, consider
your options, and prepare for the development of your Strategic
Refrigerant Plan. One of your overriding concerns, of course,
is to come into compliance with all current standards and codes.
At this point, it is highly recommended
that a code inspector be invited in to review any changes in local
code requirements. Depending on your situation, you may wish to
consult with a local building code inspector, an ARI representative
or a local member of ASHRAE. Once you're aware of the current
standards, prepare to conduct in-house code/standard awareness
training. Your OEM team member can be very helpful in this aspect
of your planning, as he or she is involved with key codes and
standards on a daily basis. Include refrigerant safety in your
training program, to be certain that everyone who handles refrigerant
knows what safe practices are, and what precautions to take. This
is very important in light of the new refrigerants with very low
exposure limits.
Explore Your Options.
In your efforts to move away from CFC refrigerants, a viable option
may be to maintain/ convert newer existing equipment. In this
instance, a positive course of action is to develop a refrigerant
agreement program in conjunction with the equipment manufacturer.
Through a service contract, the manufacturer provides you with
a guarantee of refrigerant availability and containment. This
generally requires upgrading the equipment by adding containment
devices to ensure compliance with the new emission standards outlined
in ASHRAE Guideline 3. Your contract with the manufacturer should
include an emission level guarantee to protect you from possible
refrigerant losses. It should also ensure an adequate refrigerant
supply over the life of the equipment, and a clear migration path
to HFC (chlorine-free) refrigerants.
Consider Containment Systems.
In its final ruling to enforce the U.S. Clean Air Act, EPA allows
a 15% leakage rate for commercial chillers and a 35% leakage rate
for industrial chillers. However, no one can afford to lose that
much refrigerant given the shortages that are expected during
the CFC phaseout. Containment is the first and least expensive
option. Consider the following scenario: under the ASHRAE 15-1994
recommendations, you may store 330 pounds of refrigerant on site
per system. If you reduce the leakage rate
on a typical chiller (i.e., with 500 tons of cooling capacity
and an operating charge of 1,200 lbs.) to 2%, you will have enough
serviceable refrigerant for nearly 14 years (multiply 1,200 lbs.
of refrigerant by a 2% per year leakage rate = 24 lbs; 330 divided
by 24 = 13.75 years).
Ultimately, the key question is whether you can maintain
a leakage rate of 2% in the areas of service and operations. The
answer hinges on your on-site containment devices and practices.
On-site refrigerant containment devices may be either permanently
installed, such as large storage tanks, or portable. In both cases,
careful attention to service practices is critical. Depending
on the type of equipment installed, many excellent options are
available for on-site containment:
Chillers that operate above atmospheric pressure
typically do not require all of the add-on containment devices
described above. Several reliable portable containment devices
are also on the market today. Portable devices may offer an economic
advantage in that they can be shared by many facilities. However,
it's important to check local code requirements for portable refrigerant
storage, along with local and federal transportation department
requirements.
In addition to EPA certification, refrigerant recycling
and recovery equipment that is transported between different sites
is subject to additional federal and state Department of Transportation
requirements.
Regardless of the types of containment devices you
choose to install, it's vital that a Code of Service Practice
be established for the safe handling, conservation and containment
of refrigerant. Once the Refrigerant Management Team is well-versed
in these new practice standards, a training pro-gram should be
established to educate every employee involved with refrigerant.
Replacement vs. Conversion.
The decision to replace or convert existing equipment should be
made only after a careful look at the actual costs involved in
both scenarios. Surprisingly, conversion costs can total as much
as 90% of replacement unit costs. For example, consider the conversion
of a negative-pressure chiller from CFC-11 to the nearest replacement
refrigerant, HCFC-123. Significant costs are incurred in replacing
the many chiller components (seals, o-rings, gaskets and more)
not compatible with HCFC-123, a highly aggressive solvent. Add-on
containment devices can easily add up to 25% of the cost of a
new unit (see fig. 1). Machine room upgrades required for compliance
with ASHRAE 15-1994 - refrigerant sensors, ventilation system
improvements and more - must be considered. The new ASHRAE standard
requires that any change in refrigerant be followed-up with an
inspection by the local building code authority. Finally, the
net result of a negative-pressure chiller conversion is usually
reduced capacity and lower efficiency, which affect the building
load and, hence, power costs.
Refrigerant Sensor | $6,500 |
High-Efficiency Purge | $5,500 |
Refrigerant Management System | $7,000 |
Pressurizing / Alarm System | $5,000 |
Backup Relief Valve | $4,000 |
External Oil Filter and Isolation Valve | $1,500 |
TOTAL INSTALLED COSTS | $29,500 |
Fig. 1
When comparing conversion costs to replacement costs, specify replacement units with high-quality, built-in containment devices, to avoid the expense of adding them later. Look for devices that meet the stringent standards of the American Society of Mechanical Engineers (ASME). ASME-certified vessels must be capable of performing under conditions seven times more demanding than typical operating conditions. The symbols "U" or "UM" are used to identify ASME-certified vessels.
As you compare non-CFC replacement equipment, care-fully
consider the long-term ramifications of HCFC-based equipment.
These chlorine-based refrigerants are also subject to a phaseout,
though on a slower pace than other CFCs. Safety is the watchword
in selecting new equipment: does your choice mitigate future safety
risks? Since non-CFC equipment efficiencies have improved tremendously
in recent years, be sure to factor in projected operating cost
savings from performance gains.
Each Chiller Is A Separate Case.
A general rule of thumb, and a helpful starting point for the
containment/conversion/replacement discussion, is to consider
the age of the chiller (see fig. 2). Typically, the preferred
choice for "new" chillers (less than seven years old)
is containment. Older chillers are best converted or replaced,
depending on their age and condition.
The ultimate solution is never just a matter of age,
of course. It depends in large part on the particular circumstances
surrounding each chiller.
Factors to consider include:
Once you've looked at these specifics, step back
and consider them in light of the broader issues. Consider the
question of chiller replacement in view of any modernization programs
planned for the facility. Control system upgrades, air distribution
problems and indoor air quality programs may help tip the scales
in favor of replacement now rather than later. Don't overlook
your sound requirements; performance in this area varies greatly
from one manufacturer to another. The same advice goes for manufacturers'
service contracts.
Whether you're converting or replacing, switching
from one refrigerant to another demands that you become an expert
on the new refrigerant you're considering and fully understand
its application in advance. A balance of safety, containment and
performance must be carefully reviewed. To minimize your risk,
request a performance guarantee from the chiller manufacturer,
and preferably a certification to the ARI 550-1992 Standard for
rotary and screw chillers. An ARI certification test can be conducted
on your new chiller at the factory.
Finally, consider the long-term availability of various
refrigerants (see fig. 3). As the graph indicates, HFC-134a is
forecasted to be in great supply well into the next century due
to its widespread use in a number of applications, including the
auto industry. HCFC-123 is predicted to remain in short supply
indefinitely due to its limited use by chiller manufacturers,
and its legislated phaseout by the Montreal Protocol. Although
HCFC-22 is also subject to a phaseout, a tremendous amount of
serviceable refrigerant should remain available since legislation
prohibits this refrigerant from being vented to the atmosphere.
fig. 2
fig. 3
STEP 3:
EXECUTE YOUR ACTION PLAN
Once your preliminary planning homework
is done, the team can focus its efforts on formulating the Strategic
Refrigerant Plan. At the core of this plan is your company's refrigerant
position policy, which should be stated in writing and utilized
as a benchmark for all decision-making. In essence, a refrigerant
position policy answers the basic question: "How is our company
going to address the phaseout of chlorine-bearing refrigerants?"
An effective way to organize your refrigerant plan is by site,
by building and/or by refrigerant type. In any case, the plan
should address all facilities with refrigeration equipment.
In order to ensure that your plan is
a vital, working document (versus merely a collection of commendable
goals and objectives), include an Operation/Maintenance Schedule
that clearly identifies the "who, what, where and when"
of each strategic activity. Schedules and deadlines should reflect
internal factors such as capital budgets, as well as external
factors such as equipment availability.
Analyze Return On Investment.
The plan should also include an analysis of the financial impacts
of your action plan. In evaluating containment versus replacement,
or replacement versus conversion, you'll need some quantitative
data showing which course of action yields the best return on
investment. To do this, you must consider the expected life of
the chiller, service/ maintenance costs and the cost of any necessary
building upgrades. Of course, an energy analysis should be critical
supporting evidence for your decision to replace a chiller.
An example of costs for modifications
and equipment purchases are shown in figure 4 for an at-a-glance
comparison of investment, operating costs and life cycle estimates
(see fig. 4):
Maintenance of the retrofitted machine
would increase, since containment devices would be monitored and
serviced. Operational costs would be modestly reduced, since refrigerant
is contained. Utility bills remain constant.
CONTAIN | CONVERT | REPLACE | |
Equipment (installed0 | $29,000 | $63,000 | $125,600 |
Refrigerant Charge | - | 5,400 | 6,400 |
Mech. Room Upgrade | - | 19,500 | 19,500 |
Resale of CFCs | - | (4,500) | (4,500) |
Refrigerant | |||
Leak Savings | (2%, 1,920) | (2%, 2,144) | - |
Operations: | |||
Service and Maintenance | 6,300 | 8,100 | 3,300 |
Power, Per Year | 180,400 | 184,800 | 138,600 |
TOTAL FIRST YEAR | |||
INVEST/OPERATE COST | $214,280 | $274,156 | $288,900 |
fig. 4
YEAR | |||
1 | $214 | $274 | $289 |
2 | 180 | 185 | 139 |
3-10 | 180 | 185 | 139 |
11 | 289 | 289 | 139 |
12 | 139 | 139 | 139 |
13-25 | 139 | 139 | 139 |
TOTAL OUTLAYS | $4,208 | $4,313 | $3,764 |
fig. 5
New HCFC-123 refrigerant must be purchased at about
$4.30/pound, and the same containment equipment as previously
noted must be installed. The owner also earns money on the resale
of CFC-11 (about $3.75/pound prior to reclaim). Operational costs
go up slightly for power and maintenance (this may be significant
on older chillers), but refrigerant leak reduction brings a small
savings the first year.
New refrigerant would cost about $4/pound and the
owner again earns cash on the CFC-11 aftermarket. Operational
costs drop by about 40% based on service for a new unit, and a
significant efficiency gain brings power draw to 0.63 kW/ton.
What the numbers mean.
Building ownership strategies will dictate which of the three
options makes the most sense. A number of external factors should
be examined, including how long the owner wants to keep the property,
and how the owner would like to deliver the building to a prospective
buyer.
A critical item is the change in year 11, when replacement
becomes vital for the containment and conversion routes. While
this is a normal operational year for the replacement unit, the
aging units would be replaced at about $289,000 in today's dollars.
The contain and convert options offer lower investments
up front, but the owner who replaces saves operational dollars
over years 2-11. Prospective tenants and buyers, depending on
their needs and lease terms, may be interested in either lower
operating costs or lower initial costs.
For the owner who plans to keep the building for-ever
(or at least 25 years), a more aggressive CFC phaseout plan is
recommended, based on the numbers. The replacement option works
out very well in this analysis, but cash outlays are conveniently
extrapolated over 25 years - precisely the assumed lifetime of
the replacement chiller.
Risk/Liability Assessment.
Another important component of your Strategic Refrigerant Plan
is a Risk/Liability Assessment document which addresses how your
approach mitigates risk and ensures safety. The safety issue is
especially critical in light of new equipment and refrigerants.
Companies shoulder an increased risk of liability when they adopt
a particular approach or practice with the knowledge that other
safer alternatives are avail-able. Ensuring that your company
is in compliance with codes helps to mitigate risk. Even so, every
plan should address the ramifications of a possible refrigerant
spill - what the risks are, who will be exposed, how the area
will be evacuated, where the refrigerant will go, and so on. With
your legal counsel, review the risks and liabilities associated
with refrigerant exposure in light of the exposure limits recommended
in documents such as the Program for Alternate Fluorocarbon Toxicity
Testing (PAFTT).
A proactive approach to the assessment of risk includes
a careful examination of EPA's Section 114 letter, the document
EPA sends to companies discovered intentionally venting CFC/HCFC
refrigerants to the atmosphere. Based on the content of the violator's
answers, EPA determines how much of a fine to assess (fines start
at $25,000 per day). Ensuring that you have a solid plan and answers
to the Section 114 questionnaire up-front is yet another way to
reduce your company's risk. The intent of the U.S. Clean Air Act
and EPA's enforcement rulings is to ensure that refrigerants are
not vented to the atmosphere. Having a thorough refrigerant plan
in place puts you on the path toward full compliance.
Code Compliance: A Moving
Target. Wouldn't it be simple if companies could take a "set
it and forget it" approach to code compliance? The fact is,
codes are a moving target, ever-changing and typically becoming
more stringent over time. That is why your plan must include an
ongoing training program, and
a strategy for maintaining facilities at set levels over the long
term.
This requires a mechanism for staying
abreast of new refrigerant legislation and other events that will
impact the short- and long-term refrigerant supply. What hap-pens
if refrigerants have earlier phaseouts than expected? Since a
well-maintained chiller can have a useful life of 30 years or
more, you must evaluate the long-term effectiveness of your solutions.
ONE COMPLEX ISSUE, THREE BASIC STEPS
The steps in the development of a Strategic
Refrigerant Plan - Analyze, Organize & Plan, and Execute -
are clear and straightforward. Yet the issue itself is undeniably
complex. The prospect of giving up the "lifeblood" refrigerants
that the industry has grown up with can be daunting even to the
most experienced facilities managers. The financial and environmental
impacts are profound - two excellent reasons to begin now to develop
a sound, strategic plan for your company's chlorine-free refrigerant
future. Your original equipment manufacturer stands ready to assist
with this important task, providing unique expertise and an objective
assessment of current conditions and their implications for your
facility.
Starting your refrigerant management
plan
CODE OF SERVICE PRACTICE FOR HANDLING,
CONSERVATION & CONTAINMENT OF REFRIGERANT
Objective:
To provide an industry-wide
Code of Practice for the servicing of Air Conditioning/Refrigeration
Equipment and Systems for the purpose of conserving refrigerant,
improving personal safety, and preserving the environment.
DO:
DON'T:
REFRIGERANT LOG
Date:
Technician:
Machine Data
Manufacturer: Refrigerant Type:
Model Number: Design Refrigerant Charge:
Serial Number:
Unit Identification:
Location:
Leak Identification
Leak Location:
Leak Repaired: Yes No Why Not:
Leak Detector Used:
Status/Comments:
Amount of Refrigerant Added:
Recovery/Recycle
Equipment Used:
Amount Recovered: Recycled: Yes No .
Re-installed: Yes No .
Disposition:
Status/Comments:
Amount of Refrigerant Added:
Unintentional Venting:
Situation:
Approximate Amount Vented:
Amount of Refrigerant Added:
Summary:
Total of refrigerant added as a percent of design refrigerant charge:
General Comments:
ESSENTIAL REFERENCES
Air-Conditioning and Refrigeration Institute
(ARI)
4301 North Fairfax Drive
Suite 425
Arlington, VA 22203
Phone: (703) 524-8800
Fax: (703) 528-3816
ARI 550-92 Centrifugal And Rotary Screw Water Chilling Packages
ARI 740-93 Performance Of Refrigerant Recovery, Recycling, And/Or Reclaiming Equipment
ARI-700-93 Specifications For Fluorocarbon
Refrigerants IRG-2 Handling And Reuse Of Refrigerants In The United
States (Handling Recycling Guide)
American Society of Heating, Refrigerating,
and Air-Conditioning Engineers, Inc. (ASHRAE)
1791 Tullie Circle, NE
Atlanta, GA 30329
Phone: (404) 636-8400
Fax: (404) 321-5478
ASHRAE 15- Safety Code for Mechanical Refrigeration 1994 (See Carrier Publication 819-116 for an overview)
ASHRAE Guideline-3 Reducing Emissions Of Fully Halogenated Chlorofluorocarbon (CFC) Refrigerants In Refrigeration And Air Conditioning Equipment And Applications
ASHRAE Guideline 'K' Containers For Recovered Fluorocarbon Refrigerants
ASHRAE Guideline 'N' Assignment Of
Refrigerant Containment Colors
U.S. Environmental Protection Agency (U.S.
EPA)
401 M. Street, S.W.
Washington, D.C. 20460
EPA Hotline: 1-800-296-1996
Final Ruling of Section 608 of Clean Air Act, dated May 14, 1993