Solar Energy System Sizing Sheets Sizing your solar energy system Follow the directions below and complete the work sheets and you will have a general knowledge of the number of solar panels, batteries and inverter(s) needed to go solar. Going through all of the sizing sheets will also give you a better understanding of your solar system. AC and DC Loads The appliances and devices (TV's, computers, lights, water pumps etc.) that consume electrical power are called loads. It is very important to examine your power consumption and reduce your power needs as much as possible. For more information regarding reducing your power consumption see (Living the Alternative Energy Lifestyle) Solar Electrical System Sizing Information To begin sizing a solar electrical system, you need to determine your power consumption demands. Make a list of the appliances and/or loads you are going to run from your solar electric system. Find out how much power each item consumes while operating. Most appliances have a label on the back which lists the wattage. Specification sheets, local appliance dealers, and the product manufacturers are other sources of information. Calculate your AC loads. If there are no AC loads, skip down to "Calculate your DC loads". List all AC loads, wattage and hours of use per week (Hrs/Wk) in the spaces below. Multiply watts by Hrs/Wk to get watt-hours per week (WH/Wk). Add all the watt hours per week to determine AC Watt Hours Per Week. Fill in the blanks and print the forms below to establish your power requirements. To assist your load calculations a sample of electrical loads is available below. Sample 120 Volt AC Load Chart To Calculate Your AC Electrical Loads    AC Load Sizing Worksheet  Appliance Watts X Hrs/Wk =  Wh/Wk   x   =     x    =     x   =     x   =     x   =     x   =     x   =     x   =     x   =   Sample 120 Volt AC Load Chart  Total Wh/Wk AC Loads     1. Multiply Wh/Wk Total by 1.2 to account for inverter loss =DC Wh/Wk =     2. Enter Inverter input voltage (typically 12) here     3. Divide line 1 by line 2. This = the total amp hours/week used by AC loads You need to enter this number into the DC chart below to continue.   To Calculate Your DC Electrical Loads  DC Load Sizing Worksheet  Appliance Watts X Hrs/Wk = Wh/Wk   x   =     x   =     x   =     x   =     x   =     x   =     x   =      Total Wh/Wk DC   1. Enter DC System Voltage (Typically 12)   2. Divide Total Wh/Wk DC by System Voltage This = Total DC Amp hours per week   3. Enter Total AC Amp hours per week from AC sizing sheet above   4. Add line 2 and line 3. This = total Amp hours a week for all loads.   5. Divide line 4 by 7. This is the total Amp hours per day     Your next step is to calculate your battery storage requirements. Advance to battery sizing work sheets.