Transcript Efficiency Coefficients of Energy Commodities (Ann Christin B eng, Statistics Norway)

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Efficiency coefficients of
energy commodities
Paper by: Ann Christin Bøeng, Statistics Norway
Presented by: Jun Toutain, Statistics Norway
OG4, Ottawa, 4 February 2009
Energy transfers – useful and useless
• Energy transformation – process of transforming one form
of energy into another
– Useful energy
– Useless energy
• The more useful energy, the more efficient the device is
• Energy spreads out and gets more and more useless
Example – light bulb
Light energy
(5% useful)
Electrical
energy
Heat
Energy transferred
to the light bulb
(95% useless)
Energy efficiency
•
•
•
Using less energy to provide the same level of energy service
More efficient technology or process
The efficiency depend on
–
–
–
–
the technology employed
the type and quality of the fuel used
the operating conditions
practices
Table 1 Energy efficiency coefficients
Device Energy efficiency
Combustion engine 20-30%
Electric motors 30-60% (small ones < 10 W);
50-90 (medium-sized ones between 10200 W);
70-99.99% (above 200 W)
Household refrigerators Low-end systems 20%,
High-end systems 40-50 %
Incandescent light bulb 2 – 10%
Compact fluorescent lamp About 7-9%
White light-emitting diode (LED) About 4 – 10%
Electric kettle More than 90%
Source: Wikipedia
Measurement of useful energy
•
Requires that the following be recorded
a) The main types of appliances used by final energy consumers
b) The amount of energy actually used by these various appliances,
or an estimate based on their utilization
c) The average efficiencies of these appliances when in normal use
•
Regular measurements enable the evaluation of energy
saving equipments
•
Can be used to calculate useful energy balances
– utilized energy consumption
Electricity production from fossil fuels
• The global average efficiencies of electricity production are
– 34% for coal
– 40% for natural gas
– 37% for oil
• For all fossil fuels, the global average efficiency is 36%
• Source: IEA (Energy Efficiency Indicators for Public
Electricity Production from Fossil Fuels)
Supplied energy
Power plants
Electrical energy
and heat
(useful)
For all fossil fuels,
the global
average
efficiency is 36%
Heat (useless)
Table 2 Estimated coefficients of different energy
sources and consumer groups
Energy source
Industry, mining and quarrying
Transport
Others
Coal
0.80
0.10
0.60
Coke
0.80
-
0.60
Fuel wood
0.65
-
0.65
Gas
0.95
-
0.95
Liquefied petroleum gas (LPG)
0.95
-
0.95
Motor gasoline
0.20
0.20
0.20
Kerosene
0.80
0.30
0.75
Diesel oil. gas oil. light heating oil
0.80
0.30
0.70
Heavy fuel oil
0.90
0.30
0.75
District heating
1.00
-
1.00
Electricity
1.00
1.00
1.00
Source: NOS Energy statistics 2000, Statistics Norway. Coefficients are estimates.
End-use losses
Method of calculating useful energy balance
• Utilized end consumption of energy can be achieved by
multiplying the figures for energy consumption for different
user groups and energy commodities with the coefficients in
Table 2
• Energy losses can be quantified by subtracting the utilized
energy consumption from the supplied energy consumption
Useful energy balance sheets
•
Take account of the transformation of energy in the appliances of the
final consumer
•
Present a fifth category of energy losses – those at the final consumer
stage
•
From the primary input to final consumer stage, the losses recorded are:
– Losses in the primary production/extraction process (gas flared, coal fines
lost etc)
– Transformation losses form primary to secondary sources of energy
– Distribution losses which largely affect gaseous fuels and electricity
– Consumption by the energy sector for plant operations
– Losses at the final consumer stage due to the operating efficiencies of
the appliances which transform the energy for the last time
•
A sample calculation for Norway is presented in the paper
Some points for discussion
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How to handle the difference between wanted and total effect, specially
in electrical equipment
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Other countries' practices
– How do other countries calculate useful energy, and which coefficients are
used?
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How to measure efficiency coefficients for different devices, sectors/user
groups or energy commodities?
– How often should the factors be updated.
•
Energy efficiency coefficients may well vary between countries, due to
different use and stocks of devices and heating equipment.
– Should country-specific coefficients be employed for different countries, or
can it be assumed that these coefficients are approximately the same?