The applications of grid-connected PV are wide-ranging. Grid-connected PV systems require very little maintenance. Using the electricity produced by the PV system directly in the building instead of purchasing electricity from the grid is referred to as offset. In some buildings, where the demand for electricity is steady during the day, there might be no surplus of electrical energy from the PV system , i.e. all of the electricity produced by the PV system is being used. This is important to consider when looking at the economics of a PV system. The way that electricity within the building is used must also be examined.
The lower the electricity demand in the dwelling, the greater the percentage of the electricity demand that can be provided by the PV system. Therefore it is important to try to reduce demand through behavioural changes and by using low energy / energy efficient appliances and lighting.