Do it Yourself Solar Energy

Calculate System Size

• 1

  Determine how much electricity the PV system must provide. Add up the watts of each appliance to ascertain the total kilowatt-hours required to power the items on a daily basis. Calculate the electrical needs for an entire household by computing the average daily kilowatt hours used by the household.

• 2

  Assemble the electricity bills for the past 12 months. Add the kilowatt hours for each month. Divide the total kilowatt hours by 12. This figure represents the average monthly kilowatt hour usage for your household.

• 3

  Divide this figure by 30 to arrive at your average daily kilowatt hours. Divide the average daily kilowatt hours by the average amount of sunlight for your region. The system's solar panels must produce enough wattage to meet this need.

Install Solar Panels

• 4

  Identify the best location on the roof to install the solar modules. Select a spot that allows the system to receive the maximum amount of sunlight. Check for buildings, trees or other obstacles that might shade the solar panels. Shade reduces solar panels' efficiency to convert the available sunlight into electricity.

• 5

  Use a stud finder to locate the roof rafters and mark them with a pencil. Builders usually place rafters 16 or 24 inches on center. "On center" means the measurement from the center of one rafter to the center of the next rafter. Inspect the roof to ensure you have a solid roof covering in good condition. Make any repairs as necessary.

• 6

  Install the solar module support brackets per manufacturer instructions. Predrill pilot holes, for the support bracket lag screws, in the center of the rafters. Predrilling the holes prevents accidentally splitting the rafters when inserting the lag screws.

• 7

  Use the trowel to spread roofing sealant around any penetrations made in the roof. The sealant prevents water seepage under the roof covering and into the building interior. Secure the rails in place. Follow the manufacturer's guidelines for clamping the modules onto the rails.

Wire the Solar Panels

• 8

  Follow the manufacturer's instructions and local building codes for wiring the solar array. The main wiring methods consist of series or parallel wiring techniques. Wire the panels in series to receive more voltage than a single panel can provide. The series technique connects the positive wire of one panel to the negative wire of the next panel. The amperage remains the same as for one panel. Use the parallel wiring technique to increase the amperage, but keep the voltage at the level of a single module. Connect the wires: positive-to-positive and negative-to-negative.

• 9

  Route the wires to the array's circuit combiner box. The combiner box allows fusing, which prevents overloading the circuits. Wire other electrical components, such as ground-fault protector and DC fuse switch. DC, or direct current, refers to the raw electricity created by the solar modules.

• 10

  Connect the system to the DC/AC inverter. The inverter converts DC to alternating currents (AC), which powers most household appliances. Connect the inverter to an AC-fused switch and the AC-fused switch to a utility switch. Make the final connection to the house main service panel.