# SOLAR WATTAGE CALCULATION TABLE

Note:
This page has no background so that you can print it out to do your own calculations.

We will explain the calculation (and why) then give you examples of how it is done.

You will need to do steps 1-4 for each appliance type you use.

1. Take the wattage of the appliance and multiply it by how many you are using. This gives you your total watts used (TW).
2. Take the TW and multiply it by how many hours a day it/they are used.This gives you your Watt Hours per Day (WHD).
3. Multiply the WHD by the number of days per week the appliance/s are in use (you may use your washer 2 days or 5). This gives you your Watt Hours per Week (WHW).
4. Take the WHW and divide it by 7 (the number of days in a week ). This gives you your Average Watt Hours per Day (AWHD).
5. Add all of the AWHD to calculate your total average watt hours used per day. This wiil allow you to choose the proper size energy system for your needs.

Example using 400 watt light bulbs used 3 hours a day 2 days a week on average.

1. Take the wattage of the appliance and multiply it by how many you are using. This gives you your total watts used (TW). 100 x 4 =400 (TW).
2. Take the TW and multiply it by how many hours a day it/they are used.This gives you your Watt Hours per Day (WHD). 400 (TW) x 3= 1200 (WHD)
3. Multiply the WHD by the number of days per week the appliance/s are in use. This gives you your Watt Hours per Week (WHW). 1200 (WHD) x 2= 2400 (WHW)
4. Take the WHW and divide it by 7 (the number of days in a week ). This gives you your Average Watt Hours per Day (AWHD). 2400 WHW) /7 = 343 (AWHD)

Note: It may be easier and more accurate if you do your calculations for each individual appliance (so you don't have to average out several appliances).

Appliance x Quantity = Total Watts x hours per day used = WHD x days per week used =Watt Hours per Week /7=Average Watt Hours per Day
100w Light Bulb 4 400(TW) 3 1200(WHD) 2 2400(WHW) 343(AWHD)
700w Dishwasher 1 700 1 700 7 4900 700
170w TV 1 170 3 510 5 2550 364
4w electric clock 2 8 24 192 7 1344 192
Total Average Watt Hours per Day 1599
Appliance x Quantity = Total Watts x hours per day used = WHD x days per week used =Watt Hours per Week /7=Average Watt Hours per Day
Total Average Watt Hours per Day