18 x 190 Watt Suntech STP190S-24Ad+ solar panels

3.42 kW Off Grid Solar PV System

The system shown here typically represents a stand alone solar power system (off grid solar) suitable for a domestic application occupied on a full time basis – please refer to project pages for more information about this project.

The electrical demand is approximately 16 kW/hrs per day in summer and 12.6 kW/hrs during winter. The main discrepancy for a fluctuation in electrical demand during the seasons is due to refrigeration and ceiling fans being greater in summer.

The battery bank, comprising of Exide Energystore deep cycle lead acid batteries,  reserves 3.5 days storage in the case of higher than average electrical demand or unseasonal weather. As with any correctly designed Off Grid solar power system, the battery bank remains at the heart of the system.

The solar array comprises of 18 x 190 Watt Suntech mono-crystalline solar panels and were chosen due to their high efficiencies and 25 year output warranty. The Latronics 3.5 kW inverter was chosen as it is capable of delivering 10.5 kW instantaneously and is well suited for the continuous demand.

As a whole, this off grid solar system produces 5.2 MW/hours of electricity per year, with an annual savings of $1,200 per year and over the lifetime of the batteries of 12 years an estimated saving of $16,000 if the owners had decided that the grid was a better option.