The first step in configuring your solar or wind power system is to define your load. There are two aspects you need to know: power and energy. To determine the power requirements look up the "Power Rating" on the appliances you wish to run simultaneously. Next, determine how many hours per day these loads will run.
The product of power and time is energy, usually expressed in Kilowatthours. (kWh) The energy rating (kWh) and the power rating (watts) is the most important characteristic of your load you need to define these loads.
You can also check your existing electric bill for "kWh per month" consumption. This will tell you how many kWh of energy you'll need each month.
From this information we can help you configure the proper sizing for the equipment to run these loads.
List your electrical appliances (loads) by Power demand. Then list the number of hours per day you'll use this appliance. This will be the Energy load  that is Power over Time. Once you have the energy load add up all the loads to arrive at at daily energy load in kWh (Kilowatthours).
Solar energy is an amazing resource. The power density of Solar Energy at the earth's surface is 1,000 Watts/m2. This translates into converted electricity through solar PV modules of over 10 Watts/SquareFoot.
As you design your Solar or Wind energy power supply it's useful to start at the end  that is, how much Power and Energy to you need for your load. The Power will be the maximum draw when all of your loads are turned on, and the Energy will describe how long those loads operate.
