This project has been assisted by
the New South Wales Government
through its Energy Efficiency Training Program
Energy Efficiency
through Product & Process
Design
Prepared by
Prepared by Plastics Industry Manufacturers of Australia (PIMA)
in partnership with Australian Management Academy (AMA);
executed in collaboration with EcoProducts
Copyright and disclaimer
The Office of Environment and Heritage and the State of NSW are pleased to allow this material to be
used, reproduced and adapted, provided the meaning is unchanged and its source, publisher and
authorship are acknowledged.
The Office of Environment and Heritage has made all reasonable effort to ensure that the contents of
this document are factual and free of error. However, the State of NSW and the Office of Environment
and Heritage shall not be liable for any damage which may occur in relation to any person taking
action or not on the basis of this document.
Office of Environment and Heritage, Department of Premier and Cabinet
Phone: (02) 9995 5000 (switchboard)
Email: info@environment.nsw.gov.au
Website: www.environment.nsw.gov.au
2
Energy Efficiency
through Product & Process
Design
Module 5 – Energy Systems
Units, Conversions, Measurements and Carbon
3
© Australian Management Academy and Eco Products
Agency
Key Points
1. Forms of energy
2. Units and conversions
3. Calculating greenhouse gas emissions
© Australian Management Academy and Eco Products
Agency
4
Energy
The unit of energy is the Joule (J)
Energy can be
– kinetic (movement)
– potential (stored)
– thermal, electrical, chemical or nuclear
But all have the same fundamental unit
© Australian Management Academy and Eco Products
Agency
5
Energy
1 J is a small amount of energy
106
J
Chemical energy of 3 large
bananas
1 MJ
=
1 GJ
= 109 J
Half-a-tank of petrol
1 TJ
=
1012
J
Annual energy use of 10 Australian
households
1 PJ
= 1016 J
Australian energy use: 5770 PJ/yr
© Australian Management Academy and Eco Products
Agency
6
Power
Power is the rate at which energy is used
• The unit for power is the Watt (W)
1 W = 1 J/s
• Often use kW (103 W) or MW (106 W)
© Australian Management Academy and Eco Products
Agency
7
Power
Power is typically measured in kWs or MW
Incandescent light
bulbs
Small electric motor
Plastics extruder
Coal-fired generator
25 – 100 W
1 kW
100 kW
660 MW
© Australian Management Academy and Eco Products
Agency
8
Energy Consumption
Energy consumption is measured in terms of:
Energy consumption = power x time
Electrical energy consumption is measured as:
Energy consumption = kW x hours = kWh
© Australian Management Academy and Eco Products
Agency
9
Calculating Electricity Use
Example: Electricity use by a 100 kW extruder
• At the design load (85% of maximum load), the
motor uses 85 kW of power when running
• If it is run for 6,000 h per year then annual
energy use is:
85 kW x 6000 h/y = 510 MWh/y
• At $0.15/kWh the cost would be: $76,500
© Australian Management Academy and Eco Products
Agency
10
Comparing MJ to kWh
1 W = 1 J/s and there are 3600 seconds in an
hour
Therefore,
1 1kWh
3.6 MJ
Wh ==3,600
J
Or:
In the opposite
direction:
1 MJ
= 0.278 kWh
© Australian Management Academy and Eco Products
Agency
11
Comparing Fuels and
Electricity
The energy available from fuels and electricity
cannot always be directly equated due to
conversion & transmission losses
Small diesel generator
Coal fired generators
Combined cycle gas turbine generator
Electricity transmission and distribution
grid
© Australian Management Academy and Eco Products
Agency
efficiency
25%
30% - 35%
40% - 55%
90% - 95%
12
Comparing Fuels and
Electricity
• May need to differentiate between delivered
energy and primary energy.
• Conversion and distribution losses can matter
for comparing different energy sources on a life
cycle basis.
© Australian Management Academy and Eco Products
Agency
13
Calculating Greenhouse
Gas emissions
Scope
Scope 1
Description
Emitted directly by fuel combustion or other
activities inside organization
Scope 2
Emitted indirectly through generation of
electricity purchased and consumed
Emitted by other indirect activities. These
include the emissions caused by production
and distribution of fuels and electricity.
Scope 3
© Australian Management Academy and Eco Products
Agency
14
Calculating Greenhouse
Gas Emissions
Energy source
Energy
conversion
Emission Factors
Scope
1
Scope
2
Scope
3
TOTAL
kg CO2-e per GJ delivered
Electricity (NSW)
Natural Gas (NSW) 39.3 x10-3 GJ/m3
-
249
47
297
51.33
-
14.8
66.1
Petrol
34.2 x10-3 GJ/L
66.92
-
5.3
72.2
LPG
26.2 x10-3 GJ/L
60.2
-
5.3
65.5
Diesel (Euro IV)
38.6 x10-3 GJ/L
69.75
-
5.3
75.1
Source: National Greenhouse Accounts (NGA) Factors, Department of Climate Change, 2009
© Australian Management Academy and Eco Products
Agency
15
Summary
•
•
•
•
•
Energy is measured in J
Power is measured in J/s = Watts
Energy consumption is measured in kWh or GJ
1 kWh = 3.6 GJ, 1 MJ = 0.278 kWh
Conversion efficiencies and losses need to be
considered when comparing energy sources
• Emission Factors are used to calculate
greenhouse gas
© Australian Management Academy and Eco Products
Agency
16