Phototvoltaic (PV) solar system engineering and distribution company Sinetech launched its PV solar system and weather data-capturing portal last month.

The portal combines accurate weather data with PV solar system data and can predict an accurate solar system yield.

The PV panels and weather station are installed on the roof of the company’s headquaters and together they form the first system of its kind in South Africa.

“Accurate data for solar systems in South Africa has previously been hard to find. As we are working with sophisticated software, we need accurate input data to produce accurate output data,” Sinetech GM Herbert Teubner tells Engineering News.

“The data collected is now available on the Internet and we will make it available free of charge to colleges and universities,” Teubner notes.

He explains that there are three types of solar panels used in the weather-referencing system – monocrystalline silicon solar panels, polycrystalline silicon solar panels and CIS solar panels.

Each type can generate up to 3 kW/h. The monocrystalline and polycrystalline solar arrays use 12 × 250 W panels each to achieve this output, while the CIS panels require 20 × 150 W units to achieve the same capacity.

“We no longer need to rely solely on manufacturers’ specifications – we can now confirm panel performance first-hand at our own reference site. For example, CIS panels claim between an efficiency improvement [of between 8% and 10%] over crystalline panels, owing to various factors, including the soaking effect. We will now be able to put these claims to a real-time test,” Teubner explains.

He says each solar panel array uses the same type of high-quality inverters which incorporates an MPPT, or maximum power point tracker, controller, providing clear and measurable performance indicators for those studying the data.

The rooftop installation provides uninterrupted exposure to all elements at all hours. The arrays are connected to a variety of diagnostic instruments and communications software that collect and display data in real time.

Through its weather system, Sinetech can measure conditions such as ambient temperatures, the temperatures of individual panels, solar irradiance and humidity, as well as wind speed and direction and many other measurements.

“Ultimately, the live test site will establish which solar panel is the most efficient under identical weather conditions while generating the type of data that is invaluable to other users who hope to embrace solar energy in the future,” he says, adding that, theoretically, calculated data can now be confirmed with actual figures under real South African conditions.