Residential Solar Technology Made Simple

Solar technology is used to convert the sun’s energy into useful power. Each day, the sun provides the earth with 15,000 times more energy than we use yet we extract far less than 1% of our energy needs directly from the sun.

Residential solar technology has been around for decades but is largely unknown to the general public. Now with rising energy prices and concern for climate change, solar technology is being deployed at an increasing rate.  

Solar Photovoltaic Systems (PV)

Photovoltaic comes from the words photo, meaning “light” and volt, meaning “electricity”. A solar photovol­taic (PV) system uses the sun’s light energy or photons to produce electrical current. In a typical solar PV panel, light energy from the sun strikes a silicon semi-conductor dislodging electrons causing them to flow in the PV panel which, in essence is the definition of direct current electricity.
As shown in the diagram, a solar photovoltaic system is comprised of a series of silicone solar panels connected to an inverter (our homes use alternating current so the direct current generated by the PV system must be converted to alternating by the inverter) which then supplies the home’s lights and appliances.

Most solar PV systems today are “grid connected” meaning that any excess electricity generated by the residential solar PV system is transmitted back to the into the electrical grid and used by someone else (conversely, when the sun is not out, the home draws electricity from the grid).

A residential solar PV system is typically sized to produce most of the home’s monthly electricity needs. During peak sunlight hours, the PV system will produce more electricity than the home uses. This excess electricity is transmitted back to the electrical grid causing the utility meter to spin backwards. In the evening and at night, the solar PV system will not be producing electricity and the home will draw its elec­tricity needs from electrical grid (generated by the utility company).

Over the course of the month, the meter will spin backwards when the home is producing more electricity than it is consuming and spin forward when consuming electricity from the grid. The home­owner will pay only for any net electricity used during the month. This is called “net metering”.