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TIMELY REPLACEMENT OF WHITE GOODS
INVESTIGATION OF MODERN APPLIANCES IN A LCA
Roland Steiner, Mireille Faist Emmenegger,
Niels Jungbluth, Rolf Frischknecht
ESU-services, Kanzleistrasse 4, CH – 8610 Uster, Switzerland
www.esu-services.ch
, steiner@esu-services.ch
Project funded by the Swiss Federal Office of Energy (SOFE) and Schweizerische Agentur für Energieeffizienz (S.A.F.E.)
Introduction and Goal of the Project
Timely replacement of electric household appliances (white goods) is often thought to be a beneficial option due to the energy efficiency improvements in
modern appliances. Such conclusions are often solely based on comparing the direct with the indirect (grey) energy input. The conclusions are mostly
deduced from the large dominance of the use over the production phase, disregarding other environmental effects. In this study two modern and efficient
appliances, a washing machine and a fridge freezer, are analysed with the more comprehensive indicators ecological scarcity 97 and Eco-indicator 99. The
full life cycle of the white goods with raw material extraction, production, distribution, operation, maintenance and disposal has been investigated. Fur-
thermore, special attention was given to the electronic components.
Theoretical Background
Three factors determine if a timely replacement makes sense or not:
1. the life-span of the new appliance (t
L,new
)
2. the production and disposal of the new appliance (P
new
)
3. the differences in the use phase (U) resulting from the higher effi-
ciency of the new over the old appliance (∆U)
The replacement is worthwhile when the annual savings in operation (1)
are larger than the annual amortisation of the new appliance (A
new
) (2).
This leads to equation (3) with R < 1 to indicate a beneficial timely re-
placement (the more so the closer to zero). In other words, the savings in
the use phase have at least to pay for the additional amortisation due to
the timely replacement.
∆U = U
old appliance
– U
new appliance
(1)
∆U > A
new
= P
new
/ t
L,new
(2)
R = A
new
/ ∆U (R < 1 ⇒ beneficial replacement) (3)
The Study
The full life cycle of the white goods with raw material extraction, pro-
duction, distribution, operation, maintenance and disposal has been inves-
tigated. Furthermore, electronic components, which tend to have a high
environmental impact in relation to their weight, were evaluated in detail.
The impact assessment in the LCA was conducted with the Eco-indicator
99 (EI’99) and the ecological scarcity 97 (UBP’97) methods. The cumu-
lative energy demand (CED) was also calculated to represent an energy
based analysis. The results from the fridge freezer study are very similar
to the results of the washing machine presented here in detail.
Washing Machine
A modern, energy and water efficient washing machine was analysed.
The appliance was assumed to be used in Switzerland by one single
family, which results in 300 washings a year on average. The machine
uses 49 litre of water and 0.94 kWh of electricity per standard washing (a
mix of different washing programmes). The expected life-span of the
machine is 15 years.
The results from the cumulative energy demand (CED) in Figure 1 show
a dominant role of the direct electricity consumption during the operation
of the washing machine (approx. 83%) confirming this kind of findings
from older studies. This dominance is less pronounced when the ecologi-
cal scarcity points are applied (approx. 71%). However, in the evaluation
with the Eco-indicator 99 the direct electricity consumption contributes
only 36% of the points, while the production & distribution (53%) be-
comes the dominating phase. This is contradicting the common notion of
the use phase being the most important phase in the life cycle. Chromium
steel is the most important product accounting for about 30 to 40% to
production & distribution, whereas the electronic components contribute
about 5%. In this phase the most important emissions are particles (EI’99
and UBP’97), chromium into air (EI’99) and NO
x
(UBP’97).
The results indicate that a significantly higher efficiency improvement
between the old and the new machine (∆U) is needed to make the timely
replacement worthwhile when more comprehensive indicators are ap-
plied.
To illustrate, the A
new
/∆U ratio (R) was calculated for all three evaluation
methods likewise. It was arbitrarily assumed that the modern washing
machine analysed in this study is 25% more efficient than the replaced
one. As can be seen in Table 1, the ratio is far below 1 for the CED dem-
onstrating that a timely replacement is largely beneficial. This is less
pronounced for the UBP’97 with a R-value just under one. Using EI’99
for the evaluation shows that a timely replacement is not favourable
anymore, as the amortisation of the production (A
new
) is higher than the
savings due to the replacement appliance (∆U) – the savings of energy
are too small to pay for the additional amortisation.
Table 1: Results from the calculation of a timely replacement of the washing
machine calculated with cumulative energy demand (CED), ecological
scarcity ’97 (UBP’97) and Eco-indicator ’99 (EI’99). A timely re-
placement is a beneficial option, if the condition R < 1 is fulfilled.
CED UBP'97 EI'99
R = A
new
/∆U
0.42 0.94 5.04
Replacement is:
beneficial
slightly
beneficial
not
beneficial
Conclusions
Evaluations of timely replacements with more environmentally comprehensive indicators, like ecological scarcity ‘97 and Eco-indicator ‘99, tend to result
in a lower importance of the use phase of white goods compared to cumulative energy demand. As a consequence, a timely replacement becomes less
beneficial or even disadvantageous. An evaluation based on energy or energy related data can, therefore, lead to wrong conclusions from an environmental
point of view. This becomes particularly true for highly efficient appliances like the ones analysed.
The outcome also depends on the use pattern (i.e. how often or intensively an appliance is used) and the electricity mix (i.e. the location of use). The first
aspect largely determines how much electricity is consumed, while the latter one determines how strong it is counted in the evaluation with the more com-
prehensive indicators. In order to make decisions on timely replacement it is, therefore, essential to consider such aspects carefully.
CED
83.0%
2.8%
2.5%
11.7%
0.01%
UBP'97
0.1%
22.1%
3.9%
3.1%
70.8%
EI'99
35.8%
7.4%
3.9%
52.7%
0.2%
Production & Distribution Operation (Electricity)
Operation (Water usage) Maintenance
Disposal
Figure 1: The relative shares of the different life cycle stages as resulting from
the calculation of the cumulative energy demand (CED), the ecological
scarcity points 97 (UBP’97) and the Eco-indicator points 99 (EI’99)
for a modern washing machine.
TIMELY REPLACEMENT OF WHITE GOODS – INVESTIGATION
OF MODERN APPLIANCES IN A LCA
Roland Steiner, Mireille Faist Emmenegger, Niels Jungbluth, Rolf Frischknecht
ESU-services, Kanzleistrasse 4, CH – 8610 Uster, Switzerland
steiner@esu-services.ch, www.esu-services.ch
Introduction
It is often thought that a timely replacement of electric household appliances
(white goods) can make sense due to the energy efficiency improvements in
modern appliances. Such conclusions are often solely based on comparing the
direct with the indirect (grey) energy input – i.e. from the large dominance of the
use over the production phase (e.g. [1, 2]) – and disregarding other environ-
mental effects. In this study two modern and efficient appliances, a fridge
freezer (A+ label) and a washing machine (AAB label), are analysed with the
more comprehensive indicators ecological scarcity 97 and Eco-indicator 99.
Theoretical Background to Timely Replacement
Three factors determine according to [3] if a timely replacement makes sense or
not:
1. the life-span of the new appliance (t
L,new
)
2. the production and disposal of the new appliance (P
new
)
3. the savings in the use phase resulting from the higher efficiency of the
new over the old appliance (∆U)
The replacement is worthwhile when the annual savings in operation (∆U =
U
old appliance
– U
new appliance
) are larger than the annual amortisation of the new ap-
pliance (A
new
= P
new
/ t
L,new
): ∆U > A
new
. This leads to R = A
new
/ ∆U with R < 1 to
indicate a beneficial timely replacement (the more so the closer to zero). In
other words, the savings in the use phase have at least to pay for the additional
amortisation due to the timely replacement. This simplified approach, which is
independent of the point in time of the replacement, is valid only for a short time
perspective. On a long term view, it might be more favourable to wait for an
even more efficient appliance, which results in a larger ∆U and eventually in a
better overall result. However, this approach needs assumptions on the devel-
opment of the efficiency into the future, which contains an additional degree of
uncertainty. An extended description of both approaches including the complete
mathematical background, are presented in [3]. A similar approach, but for
evaluating the optimum lifespan of a population of appliances, instead of a sin-
gle one, has been proposed by [2].
Timely Replacement Analysis of White Goods
The full life cycle of the white goods with raw material extraction, production,
distribution, operation, maintenance and disposal has been investigated. Fur-
thermore, electronic components, which tend to have a high environmental im-
pact in relation to their weight, were evaluated in detail. The impact assessment
in the LCA was conducted with the Eco-indicator 99 (EI’99) and the ecological
scarcity 97 (UBP’97) methods. The cumulative energy demand (CED) was also
calculated to represent an energy based analysis.
Washing Machine
A modern, energy and water efficient washing machine was analysed [4]. The
appliance was assumed to be used in Switzerland by one single family, which
results in 300 washings a year on average. The machine uses 49 litre of water
and 0.94 kWh of electricity per standard washing (a mix of different washing
programmes). The expected life-span of the machine is 15 years.
CED
83.0%
2.8%
2.5%
11.7%
0.01%
UBP'97
70.8%
3.1%
3.9%
22.1%
0.1%
EI'99
35.8%
7.4%
3.9%
52.7%
0.2%
Production & Distribution Operation (Electricity)
Operation (Water usage) Maintenance
Disposal
Figure 1: The relative shares of the different life cycle stages as resulting from the calculation
of the cumulative energy demand (CED), the ecological scarcity points 97 (UBP’97) and the
Eco-indicator points 99 (EI’99) for a modern washing machine.
The results from the cumulative energy demand (CED) in Figure 1 show a
dominant role of the direct electricity consumption during operation (approx.
83%) confirming this kind of findings from older studies [1, 2]. This dominance is
less pronounced when the ecological scarcity points are applied (approx. 71%).
However, in the evaluation with the Eco-indicator 99 the direct electricity con-
sumption contributes only 36% of the points, while the production & distribution
(53%) becomes the dominating phase.
The latter result means that a significantly higher efficiency improvement be-
tween the old and the new machine (∆U) is needed to make the timely re-
placement worthwhile when more comprehensive indicators are applied. To
illustrate, the A
new
/∆U ratio (R) was calculated with the arbitrary assumption that
the new washing machine (the one analysed in the study) is 25% more efficient
than the replaced one and for all three evaluation methods likewise. As can be
seen in Table 1, the ratio is far below 1 for the CED demonstrating that a timely
replacement is largely beneficial with this assessment. This is less pronounced
for the UBP’97 with a R-value just under one. Using EI’99 for the evaluation
shows that a timely replacement is not favourable anymore, as the amortisation
of the production (A
new
) is higher than the savings from the replacement (∆U) –
the savings are too small to pay for the additional amortisation.
Table 1: Overview of the results for the washing machine calculated with cumulative energy
demand (CED), ecological scarcity ’97 (UBP’97) and Eco-indicator ’99 (EI’99). A timely re-
placement is a beneficial option, if the condition A
new
/∆U < 1 is fulfilled, i.e. R smaller than 1.
CED UBP'97 EI'99
(MJ-eq./a) (UBP/a) (pts./a)
Amortisation (New machine) (A
new
) 4.2E+02 3.9E+04 3.60
Operation (New machine) (U
new
) 3.0E+03 1.2E+05 2.14
Operation (Old machine) (U
old
) 3.9E+03 1.6E+05 2.85
∆U = U
old
– U
new
9.8E+02 4.1E+04 0.71
R = A
new
/∆U 0.42 0.94 5.04
Whether or not timely replacement is advantageous not only depends on the
evaluation method, but also on the assumption of the number of washings per
year. The more often the machine is used, for example, the more important the
use phase becomes and, hence, the higher the potential savings (∆U), which in
turn lowers the ratio R. The country of operation needs also to be considered,
since the effects from the electricity consumption contributes an important share
in the assessments of the washing machine. Country or site specific electricity
mixes that score differently from the Swiss electricity mix used in this study, will
result in an increased or decreased importance of the use phase [5]. These as-
pects can significantly influence the decision on timely replacements.
Fridge Freezer
A modern, energy efficient fridge freezer (a fridge and a separate freezer com-
bined in a single appliance) was analysed for this study [6]. The net volume is
192 l for the fridge and 92 l for the freezer compartment. The annual energy
consumption is 194 kWh. The fridge freezer is assumed to be operated in Swit-
zerland and, as a consequence, using the Swiss supply electricity mix.
CED
79.7%
0.1%
0.6%
19.6%
UBP'97
72.0%
0.9%
0.7%
26.5%
EI'99
36.6%
1.1%
1.7%
60.6%
Production & Distribution Operation (Electricity)
Maintenance Disposal
Figure 2: The relative shares of the different life cycle stages as results of the calculation of
the cumulative energy demand (CED), the ecological scarcity points 97 (UBP’97) and the Eco-
indicator points 99 (EI’99) for a modern washing machine.
The LCA results of the fridge freezer are rather similar to those of the washing
machine. The direct electricity consumption during operation is the most impor-
tant in cumulative energy demand (approx. 80%), a bit less in UBP’97 (72%)
and in EI’99 production & distribution (61%) becomes more important than the
electricity consumption (37%).
It is to be expected that the efficiency of the fridge freezer deteriorates over time
due to aging of e.g. the insulation material, the seals and the cooling system
itself leading to a certain underestimation of the use phase. This effect is mainly
associated with cooling appliances, however. For other types of white goods the
deterioration in efficiency is expected to be of minor importance [2].
Conclusions
Evaluations of timely replacements with more environmentally comprehensive
indicators, like ecological scarcity ‘97 and Eco-indicator ‘99, tend to result in a
lower importance of the use phase of white goods compared to cumulative en-
ergy demand. As a consequence, a timely replacement becomes less beneficial
or even disadvantageous. An evaluation based on energy or energy related
data can, therefore, lead to wrong conclusions from an environmental point of
view.
The outcome also depends on the use pattern (i.e. how often or intensively an
appliance is used) and the electricity mix (i.e. the location of use). The first as-
pect largely determines how much electricity is consumed, while the latter one
determines how strong it is counted in the evaluation with the more comprehen-
sive indicators. In order to make decisions on timely replacement it is, therefore,
essential to consider these aspects carefully.
To achieve a high efficiency during operation the appliances are equipped with
elaborate electronic controls, thicker insulations and other technical means,
which turn the production more complex and in the case of the fridge freezer
also more material consuming (increasing A
new
). However, this might be bal-
anced out by optimised construction and materials. On the other side the poten-
tial for savings is becoming smaller for efficient devices (decreasing ∆U), since
they converge to the limitations of a technology (law of diminishing returns) [2].
The latter effect can, therefore, induce a shift towards a higher share of the pro-
duction phase in all evaluation methods (R is becoming larger). This implies that
the more efficient an appliance is, the less favourable a timely replacement
might become. [2] found also an increased optimum life-span for newer appli-
ances involving the same effect.
It can be said, as a final conclusion, that from a comprehensive environmental
analysis an extended service life can become the more environmentally benefi-
cial option than an early replacement. This becomes particularly true for highly
efficient appliances like the ones analysed.
References
[1] N. Morelli, 1998. "Scenarios for Eco-Efficiency: Technical Change and
Factor 10 Reduction in Household Appliances." RMIT University, Mel-
bourne.
[2] A.M. Chalkley, E. Billett, D. Harrison, G. Simpson, 2003. "Development of
a method for calculating the environmentally optimum lifespan of electri-
cal household products". Proc. Instn Mech. Engrs., 217(Part B), pp.
1521-1531.
[3] R. Frischknecht, P. Hofstetter, 1993. "Rückzahldauer bei vorzeitigem Er-
satz; Theoretisches Modell und Beispiele für Ökobilanzen". Arbeitspapier
6, Gruppe Energie - Stoffe - Umwelt, Institut für Energietechnik, ETHZ,
Zürich.
[4] M. Faist Emmenegger, R. Frischknecht, 2004. "Ökobilanz Waschautomat
V-ZUG". Uster.
[5] R. Frischknecht, M. Faist Emmenegger, 2003. "Strommix und Strom-
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logischen Vergleich von Energiesystemen und den Einbezug von Ener-
giesystemen in Ökobilanzen für die Schweiz, Dones, R., Editor. Paul
Scherrer Institut Villigen, Swiss Centre for Life Cycle Inventories: Düben-
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