ASHRAE Journal - December 2019 - 29

TECHNICAL FEATURE

current waste streams for appliances with refrigerants
and discusses the regulations and new waste streams
that are attempting to reduce the environmental impact.

FIGURE 1 Estimated material weights of U.S. air-conditioning units for 2014.

250,000
200,000

Figure 1 identiﬁes the material quantities for residential and commercial units that were sold; however, it is
not clear from this chart what ends up in the landﬁll.
Appliances with refrigerant take various paths at the
end-of-life including, recycling, reselling, and some are
thrown away in U.S. landﬁlls. The U.S. Environmental
Protection Agency (EPA) reported that 4.2 million metric
tons, or 1.8%, of waste arriving at landﬁlls was because
of major appliances, of which 2.4 million metric tons
were recycled. This resulted in 1.8 million metric tons
of major appliances that ended up in landﬁlls (not
recycled) in 2014.3 Major appliances include residential and commercial air conditioners, washers, dryers,
dishwashers, water heaters, refrigerators and freezers.4
Because the EPA does not split up waste further than
major appliances, the sales and shipment numbers2,5
for 2014 were used as an approximate percentage of
each appliance that was thrown away. These percentages
were then used to determine the weight of each appliance in landﬁlls. Various factors such as metal content
and local incentives may affect the recycling rate compared to sales and shipment numbers that were used
to estimate percentage of waste for different categories
of major appliance. Table 1 summarizes the weight of
speciﬁc appliances put in landﬁlls as well as the possible reduction of material weight in landﬁlls with an
increased recycling rate across the United States for
2014. Residential air conditioners include dehumidiﬁers, mini splits, window units, and split systems up to 5
tons (17.6 kW).
Table 1 illustrates the large amount of waste ending
up in landﬁlls. Half a million tons of landﬁll material
were because of residential air conditioners alone. Even
though landﬁlls record a 58% recycling rate, more optimized waste streams could increase the recycling rate up
to 84% as shown in Figure 1. With an increased recycling
rate, an additional 453,600 metric tons of material from
major appliances with refrigerant could be recycled.
One factor that the municipal solid waste report does
not account for is the emission of refrigerants, which as
stated previously has a very large environmental impact.
The EPA compiled estimates of refrigerant leakage

Weight (Metric Tons)

HVAC Environmental Impacts

Residential

Commercial

150,000
100,000
50,000
0

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Wir

ant

ger

ri
Ref

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Mo

rs

sso

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Com

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rou

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Non

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ycla

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No

TABLE 1 Major appliances disposed in landfills annually.
DESCRIPTION

PERCENTAGE
OF MAJOR
APPLIANCES BY
WEIGHT

WEIGHT OF REDUCTION OF LANDFILL
LANDFILL WEIGHT WITH IMPROVED
APPLIANCES RECYCLING RATE (TONS)
(TONS)

Residential Air Conditioners

26.3%

511,100

314,995

Fridges and Freezers

13.7%

265,076

166,368

Commercial Air Conditioners

0.7%

13,962

8,605

Other (No Refrigerant)

59.3%

1,149,861

708,667

rates from appliances and air conditioners as show in
Table 2.6,7 Were even a small percentage of units ending up in the landﬁll emitting refrigerants, the impact
would be signiﬁcant. As an example, end-of-life emissions as described in Table 2 would result in release of
3,630 metric tons of the 25,400 metric tons of R-410A
from residential and commercial AC systems. This is
equivalent to 7.2 million metric tons of CO2. However,
refrigerant impact goes further than the end-of-life
stage. Refrigerant loss can happen at any stage of an
HVAC system's life.
Most refrigerant losses occur during operation and
end of life, but there is a wide variation depending on
management and maintenance practices. From an
HVAC system owner standpoint, refrigerant loss represents a reduction in performance and a signiﬁcant
ﬁnancial impact. To reduce operation loss, tighter leak
detection and repair methods should be employed. The
method for recovering refrigerant at the end of life is
also important to ensure that most refrigerant is recovered and either banked for later use or destroyed to
ensure that it does not escape to the atmosphere, both
D E C E M B E R 2 0 19

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