In this step we choose whether you wish to be connected to the grid (Grid-Tie System), or if you are not connect to the grid (Stand-Alone System).
Define your system as Grid-Tie, or Off-Grid.
Define your system as Solar PV powered, wind generator powered, or both.
Define your loads as DC, or AC. Define the power required, and the hours you'll need that power (energy) in kWh.
Grid-Tie Systems: in a solar grid-tie system a battery bank is not necessary, but can be optional, depending on the inverter type. The panels are connected to an inverter (typically a TRACE SunTie inverter) which connects directly to the electric panel in your house.
This system delivers power directly into the grid, effectively turning your electric meter "backward". Net Metering is a process where your total electric bill is determined each month based on two things: how much electricity you consume, and how much you produce. If you produce what you consume, then you have a net-zero electric bill. If you produce half of what you consume, then you have a credit for the power you produced. This is the essence of net-metering.
Stand-Alone Systems: in a solar Stand-Alone System you have batteries because some means of storing the solar energy you generate is required. The typical components are: solar PV panels, charge-controller, battery bank, safety disconnect, and inverter. (If you are only running DC loads you don't need the inverter).
Use Solar PV panels such as REC Solar 250 watts 24 VDC for solar battery charging. Wind generators such as Air X, Air 30, Air 40, Air Breeze Marine, and Whisper 100. Charge your batteries at 12/24/48 VDC.