Polycrystalline silicon array, dual axis tracker
Dual axis tracking systems adjust the array’s tilt up and down, as well as moving from east and west through the day. This allows for the change in the sun’s height in the sky through the year.
Solar panels are best able to generate electricity from light hitting their surface directly. Adjusting their surface to follow the path of the sun increases their electricity production.
The cost of a dual tracking system is weighed against the gain that it offers a fixed array. The outputs from the solar forest’s fixed, single tracking and dual tracking arrays can quantify this advantage for an installation in Central Australia.
These dual axis trackers respond to light sensors on the face of the array. The control system determines whether the available light is mostly direct or diffuse. In diffuse or cloudy conditions, the tracker will react with less sensitivity, to limit its readjustments through the day.
The touch screens at the Interpretive Centre can be used to compare the input of this array compared to the fixed and single axis installations over the life of the system.
| Electricity produced (annual): | 11.8 MWh* |
|---|---|
| System size: | 5 x 1.1 kW |
| Array area: | 5 x 8.1 m² |
| Number of panels: | 5 x 8 |
| Panel efficiency: | 13.5% |
| Panel type: | Kyocera KD135GX |
| Panel rated output: | 135 W |
| Inverter size, type: | 5kW, SMA SMC 5000A |
| Type of tracker: | WattSun, A2125 |
*This figure is based on an assumption of 1.622 MWh annually, per kWp of installed solar panels. This may prove to be a conservative estimate for Alice Springs. A gain of 35% has been assumed for the tracker.