From: Essential Information <ei@igc.apc.org>
Newsgroups: sci.energy
Date: 31 Dec 92 13:54 PST
Subject: Re: Energy Ideas - HVAC-2
Nf-ID: #R:cdp:1466300134:cdp:1466300139:000:5940
Nf-From: cdp.UUCP!ei    Dec 31 13:54:00 1992



SELECTING A SAFE REFRIGERANT FOR COMPRESSION SYSTEMS

The combination of environmental and legislative pressures is
making the switch from chlorine- and bromine-containing
refrigerants to alternatives a necessity. By purchasing
alternatives to chlorofluorocarbons (CFCs) and
hydrochlorofluorocarbons (HCFCs), federal, state and local
governments can use taxpayer funds to benefit the public by
accelerating the introduction of alternatives into the market, a
crucial step to slowing and stopping the rate of depletion of the
ozone layer.

Benefits of CFCs and HCFCs Overstated

The supposed benefits of both CFCs and HCFCs have recently been
called into question. While CFCs have been known as effective
refrigerants, freon and other CFCs can cause fatalities at high
exposures. At medium levels of exposure, CFCs can cause lung
infections, kidney damage and tumors. At low exposures, they can
cause forgetfulness and dizziness. Manufacturers hid information
revealing their toxicity. As reported in the January-February,
1991 San Jose, California, Metro ("Breathing Uneasy," p. 12), "Du
Pont Co.~s own experiments in the early ~80s on CFC-113 [freon]
called attention to the danger but Du Pont obscured the ...
evidence, burying it at the back of a 1,700 page report." 


The reported success of HCFCs at reducing ozone depletion has
also been overstated. According to an article in the February 23,
1992 Washington Post ("Study Finds CFC Alternatives More Damaging
Than Believed"), the lower ozone-depleting potential of HCFCs was
incorrectly calculated. As the article states, "HCFCs are 95
percent less ozone-depleting than the original compounds only if
the analysis assumes that the alternatives release chlorine at
the same slow rate as CFCs. In fact ... they free chlorine much
faster; and because the coming years are critical for arresting
the chlorine buildup, the contributions of HCFCs will be ~far
higher~ than indicated by the earlier analysis of their
destructive power." HCFC-22 is only 75 percent less
ozone-depleting than CFCs, as opposed to the 95 percent figure
originally determined.

Legislation in Effect

In accordance with federal law, U.S. manufacturers will stop
making CFCs as of December 31, 1995. This deadline, established
by President Bush under the authority of the Clean Air Act
Amendments (CAA) of 1990, is earlier than the January 1, 2000
deadline established by the Montreal Protocol, an international
agreement. In addition, while the Montreal Protocol only calls
for voluntary phaseout of hydrochlorofluorocarbons (HCFCs), the
CAA calls for a mandatory total phaseout by 2030. 

According to an article in the March, 1992 Energy User News
("Users Worry About Price, Supply with Faster CFC Phaseout," p.
1), the U.S. Environmental Protection Agency (EPA) is seeking to
halt production of three HCFCs by the year 2005 in new equipment
and by 2015 in existing equipment. According to the article,
these three refrigerants have been targeted because of their
"high ozone depletion potentials relative to such other HCFCs as
[HCFC-]123."

The EPA also seeks to penalize the release of CFCs into the
atmosphere by systems which currently use them. Pursuant to
Section 608 of the CAA, the EPA has proposed that the release of
refrigerant while repairing an air conditioning system is subject
to a $25,000 fine. In addition, the EPA is calling for voluntary
certification of air conditioning service personnel.

Alternatives Have Been Developed

According to a 1992 report by the Institute for Energy and
Environmental Research (IEER), of Takoma Park, Maryland, certain
refrigerants and other technologies can successfully eliminate
the ozone depletion threat posed by air conditioning and
refrigeration systems. Chief among these are HFCs.

HFCs are close in their thermodynamic properties to CFC-11 and
CFC-12, but contain no chlorine or bromine. IEER reports that
HFC-134a is the "most promising candidate in the short-term for
use in existing vapor-compression systems using CFC-12 and in
stationary and mobile air-conditioning systems." HFC-134a is
non-toxic and non-flammable and performs about as well as CFC-12.
Research on compressor designs, lubricants and refrigeration have
indicated that HFC-134a can perform as well as, if not better
than, CFC-12. HFC-134a can be used in place of CFC-12 or R-500 in
water chillers, both as a "drop-in" substitute in existing
systems and in new designs.

As reported by Energy User News, manufacturers have not proposed
HFC-134a as a substitute, but rather focused on mixtures of other
HFCs, particularly HFC-152a, HFC-125 and HFC-32. IEER reports
that HFC-152a performs better than both HFC-134a and CFC-12 in
terms of energy efficiency and the necessary lubricants are not
as expensive. HFC-152a is highly flammable, though IEER reports
that its application in smaller systems should be entirely safe.
The HFCs should ultimately prove to be the safe alternatives to
CFCs.

CASE STUDY:

Recycling Refrigerants in School District
In accordance with federal law, Page, Arizona Unified School
District #8 has eliminated the venting of CFC~s into the
atmosphere by using a refrigerant recovery recharge unit. This
lightweight unit (weighing 27 pounds) may be carried to the
rooftop units and evacuates the refrigerant, storing it in a
container. A separate unit purifies the refrigerant prior to
replacing it in the air conditioner. The evacuator and purifier
cost a total of $3,100 and have saved $1,600 annually by
eliminating the purchase of additional refrigerant. The
maintenance staff reports that the unit has been extremely
reliable. While the school board initially considered purchasing
this system to save money, the 1990 Clean Air Act Amendments,
which may establish a $25,000 fine for releases of CFCs, made it
a priority. (Contact: Jack Gritton, Maintenance/Refrigeration,
Page Unified School District #8, Box 1927, Page, AZ 86040,
(602)645-8801.)


Newsgroups: sci.energy,talk.environment,sci.environment,alt.activism,talk.politics.misc