This document provides information about calculating household electricity bills. It explains that electricity is measured in kilowatt-hours (kWh) and gives examples of how to calculate daily and monthly electricity consumption using wattages and hours of use for different appliances. It also discusses best practices for reducing electricity bills such as using appliances off-peak, maintaining HVAC systems, and switching to energy-efficient bulbs.

1. HOUSEHOLD
ELECTRICITY
BILL
COMPUTATION

2. INTRODUCTION
• Electricity is a form of energy and it
occurs in nature, so it was not “invented.”
• Benjamin Franklin for
discovering electricity. Benjamin Franklin
had one of the greatest scientific minds of
his time.

3. ELECTRICITYMETER
• Electricity meters read inkWh (kilowatt-
hour)
–this is a unit of energy: power times
time
–1 kWh is 1,000 W over 1 hr = 3,600
seconds
• or 1 W over 1000 hours, or 100 W over
10 hours
•– thus 1 kWh

4. House hold electricmetres
• Its is used to measure electricbill

5. ORSIMPLECALCULATION
• 4 Bulb of 100W and use it 6 hours per day,
Also you have 4 fans of 60W each and the usage is
8 hours perday
• So your total energy consumption will be =4x100x6
+4x60x8 = 4320 Wh perday
Per monthly consumption will be = 4.32x30 =73.92
KWh =73.92
• The cost of 1 KwH is 10 php
• Therefore ,The Total cost will be
73.92x10.0= 739.2php

6. Reading electricity dials
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Let’s say you want to read a utility electricity meter…
Be careful to note the direction of the numbers (usually
flips back andforth)
Rounddown is the safe bet
Note the third dial below looks like 5, but it’s really 4.9
(next digit is anine)
– so looking at next dial helps you figure out rounding
– note second dial halfway between 0 and 1: next digit ~5
This meter reads5049.9
– the 9.9 reads between the lines in the last dial

7. Measuring the wheelrate
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Recall that the Kh constant is Watt-hours per turn of the disk
– so power is Kh3600diskrate
– units are: (Watt-hour)(sec/hour)(turns/sec)
On top of the rotating disk are tick marks with labels every
10 units.
– 100 units around disk
If disk is moving slowly, can measure half a rotation*
– example: from 30 to 80 or 70 to 20
If disk is moving fast, can measure time for 5 or 10 rotations
The the turns/sec could be, for example:
– 0.5 turns / 132.0 sec  98 W for Kh  7.2
– 10 turns / 44.0 sec  5890 W for Kh  7.2
– 0.2 turns / 35.0 sec  148 W for Kh  7.2

8. Example day electricity profile
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Run microwave (1000 W) for 12 minutes total (0.2 hr)
– 0.2 kWh
Clothes washer (300 W) for 1hour
– 0.3 kWh
Clothes dryer (5000 W) for 1hour
– 5 kWh
Movie on TV/DVD (200 W) for 2hours
– 0.4 kWh
• Desktop computer (100 W) on allday
– 2.4 kWh
Refrigerator (average 75 W) on all day
– 1.8 kWh
Lights (total 400 W) for 5 hours
– 2 kWh
Total comes to 12.1kWh: not too different from
average usage

9. Energy Profile
• Looking at my bills April 2018–March
2019, I saw that my household (2 people)
used:
– 3730 kWh of electricity in a year  10.3 kWh/
day

10. BESTTIPS TOREDUCEOURELECTRICITYBILL
• Refrigerator and freezer
• Automatic dryers are good, but not good for the health of
your electricity bill
• Turning on all the gadgets simultaneously
• Do you use air conditioners?
• Off-peak times could be a great idea
• When did you check on your HVAC (Heating, ventilation, and
air conditioning) the last?
• What temperature does your home water heater run on?
• Washing machine and dish wash hacks
• Dimmer switches
• Look for energy star label when buying appliances
• Again dishwasher
• Microwaves
• Compact fluorescent lightbulbs
• Plant a lot of trees