This second lecture in the series of energy topics explains the concepts of energy conversion and some of the appliances used. It highlights energy loss, and the need to maximize energy efficiency. It concludes with an energy audit, which is basically a method to calculate one's energy use, or the energy use of a building, family or a nation.
9. Appliance Power rating
(W)
Appliance Power rating
(W)
Ceiling Fan 100 Well Pump (1/3
– 1 HP)
480-1200
AC 5,000 Laptop 60-250
Oven 3,000 Plasma TV 339
Hair Dryer 1,538 Video Game 195
Dishwasher 1200-1500 Satellite dish 30
Coffee
Machine
1,500 Cell Phone -
recharge
0.25 – 0.40
Microwave 1,500 Refrigerator/
Freezer
1200 – 1400
Wh/day
Iron 1,100 Computer 120
10. Energy Appliances (2)
• Office space (7.8 kWh/sq ft)
• Street lighting (100 W – 250 W)
• Flour Mills Plant in Apapa for example, has 11 General Electric
(GE) Jenbacher gas generators at its Apapa Mills, with a
combined capacity of 30 MW. It also has a 30 MW diesel plant
at the same site as a backup.
11. Energy Appliances (3)
• Roll milling machine (Their
range of power ratings
extends from 0.5 MW up
to 16.5 MW at speeds of
between 20 and 1500
rpm.)
• Cement industry (“The
cement industry is the
most energy intensive of
all manufacturing
industries” –EIA 2013)
(100-140 KWh/ton of
cement)
Ref: Donald I. Bleiwas. Estimates of Electricity Requirements for the Recovery of Mineral
Commodities, with Examples Applied to Sub-Saharan Africa, 2011
13. Energy Audit
Name: Abdulbakre Ngozi School:
S/N Appliance Quantity Power
rating
Amount of
hours used
Total energy
1 Cooker 1 400 W 3 hrs 1200 J (KWh)
2 Washing
machine
1 500 W 2 hrs 1000 J
3 Electric iron 2 200 W 1 hr 400 J
4 TV 3 140 W 5 hr 2100 J
5 Home theatre 1 130 W 5 hr 650 J
6 Computer 5 50 W 7 hr 1050 J
Total 6400 J/day
Hinweis der Redaktion
Ever since the start of the industrial revolution, energy conversion devices have become more sophisticated and complicated.
Play video as a summary:
https://www.youtube.com/watch?v=90M2a2kEqWc
0-40 sec
https://www.youtube.com/watch?v=V08Bn3Al3RY
0-30sec
1:12 – 1:50 sec
2:58-3:33
There are so many ways to conserve energy:1) By using only for the basic requirement: We need our air conditioner only when we are at home and that too only in summer seasons. So, just switch off the ac when it is not in use.2) By avoiding over use:You heat a liquid on a stove only up to the required temperature. Carelessly heating that beyond the required temperature and then waiting for that to cool down is a waste of energy. In addition there is a possibility of the the liquid getting spoiled in the process of over heating.3) By using natural energies: Use of solar energies like solar water heaters save your electrical energy by limiting the use of electrical heaters.4) By proper maintenance: In many cases water is pumped up to a over head tank and the water stored in it can be drawn through water taps when needed, using the free gravity flow. A leak in the over head tank or leaving the taps open when not in use may lead to waste of the potential energy stored in the over head tank.5) Use of natural energy resources: