Life-Cycle-Assessment for Stoves and Ovens - ESU-services Ltd.

Inventory Analysis
timated to be 54% (Jungbluth 1995). The efficiency of the wood stove is estimated to be 70%
considering that the energy used for heating would be only a lost if it is not wishful, e.g.,
while using the stove in the summer. Here the figure for an open 3-stone fire is estimated to
be 15%.
Fig. 3 shows the range of figures investigated by various authors as shown before for the efficiency
of different types of cookstoves. A further comparison in chapter 3.1 will look on a
wide range of efficiencies possible for the various stoves in a sensitivity analysis.
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
E-Grill/Oven
Electricity Gas Wood Kerosene
E-Microwave oven
E-Cast Iron Plate
E-Glass ceramic
plate
E-Induction stove
Fig. 3 Range of figures for the efficiency of various cookstove types (Sources quoted in the text)
2.2.3 Specific Energy Use of Stoves
E-Immersion heater
Calculation for the environmental impacts can also be made with a known amount of energy
used and the calculated values of the modules „Energy in Stove“. Tab. 7 shows the energy use
per minute for various types of cooking appliances. A multiplication of the figure for the energy
use in a certain time, e.g., 30 minutes of cooking on an electric stove, with the corresponding
results of the LCI for this appliance makes it possible to calculate the environmental
impacts.
Data for gas ovens were not available. Figures for the power of plates give normally the
maximum value. If the plate is not used on the highest level or if it is switched off automatically
during longer periods of cooking using an electric stove, the energy use is lower (shown
here as the Minimum figure). This is also shown by the figure „Electric oven (warm-up + constant
use) that is measured in a standardized way 13 . The figures for the wood stoves give the
energy use for a combination of heating and cooking. The percentage of energy used for
cooking is about 60% if the full area available for this purpose is used. Thus, for a winter
13 The test describes the energy use of an oven to reach a temperature of 200°C and to hold this temperature for
one hour (Herd-Info 1996).
G-Grill/Oven
- 8 -
G-Open flame
G-Improved
W-3-stone fire
W-stove
W-stove&heating
K-Stove