1) PV panels - The single biggest cost for any homemade solar power system. PV panels are generally made from joining multiple Photovoltaic (PV) cells together.
In general, the PV module of a residential solar power system can cost from 40 to 60 percent of the total project cost. Breaking it down even further, it costs around $5 per watt from the PV panels.
2) DC to AC inverter - The power inverter is the second most expensive component next to the Photovoltaic panels. The inverter takes the low-voltage, high-current signal from the panels and change them to 120 VAC, which is directly compatible with the power grid.
3) Mounting equipment - There are 2 types of mounting, ground and roof mounting. If you are placing the PV panels on ground level, you need a ground mount. This type of mounting is more expensive because you need to cast a concrete foundation with special frames.
A roof mounting is generally cheaper because all you need is a light weight metal frame, brackets, nuts and bolts.
4) Disconnect switch - This component is important for the safety of the entire solar power system and your house. Do not try to be cheap on this item.
If there is a problem with the solar system, you want the disconnect switch to automatically cut off the circuit. Failing to do so will cause major damage to the system. Worst still, causing fire that will destroy your house.
5) Wiring and fuse box connections - The wiring components are inexpensive. The major expense is on the labor cost. If you are engaging a solar contractor, a bulk of the project budget will be on the manpower expenses.
6) Utility power meter - The power meter is usually provided by the utility company so a service technician can come to your house to inspect your system. It is also used to track the amount of power flowing back into the power grid if your residential solar setup is an intertie system.
