A Typical Solar System

The PV array consists of a number of individual photovoltaic modules connected together to give the required power with a suitable current and voltage output. Typical modules have a rated power output of around 75 - 120 Watts peak each.

An inverter is used to convert the low voltage DC to higher voltage AC.

Other components in a typical grid-connected PV system are the array mounting structure and the various cables and switches needed to ensure that the PV generator can be isolated both from the building and from the mains.

A meter will be required to ensure that the system owner can be credited for any PV power fed into the mains supply.

The roof of an average home has more than enough space for panels to provide for efficient electrical needs. A typical panel measures four feet by one foot in size and generates approximately 50 watts of electricity in bright sunshine, at a cost of approximately $10(Cnd) per watt. A typically inefficient house uses 10 kilowatts (a kW is 1,000 watts), but an efficient one needs less than 1 kW maximum and only about 100 W on average — which can be provided by about 10 four-square-foot panels. Most PVs have a 20-year warranty, but are designed to last 40 years or more. The other components of a PV system, such as batteries and inverters, require maintenance and replacement after several years.