An independent study by engineering consultancy Arup has examined the performance of thin film photovoltaic (PV) modules against poly- and mono-crystalline silicon PV in a utility-scale setting at three sites in South Africa.
The research, which was commissioned by First Solar, examined the projected energy yield of four modules (one thin film, two polycrystalline and one monocrystalline) from different manufacturers, using three hypothetical solar PV plants.
Each hypothetical plant had a capacity of 84MW in the South African cities of Bloemfontein, Upington and Vryburg.
Importance of the simulation’s locations
Nick Strevel, technical sales manager at First Solar told ESI Africa that the choice of Bloemfontein, Upington and Vryburg were due to their ideal meteorological conditions.
Strevel said: “They represent a diverse set of climatic conditions across the country. It was important to feature sites that had different temperature profiles to show the sensitivities of those conditions to energy performance and yield. All three of these sites are home to planned or proposed solar plants at this point.”
He added: “Every location needs precise information specific to the condition experienced there, however this report does identify and illustrates some of the trends associated with the performance of the products in those climatic conditions.”
Objective of the hypothetical exercise
The objective for this report was to examine the energy yield probability for the first year of production, factoring in site-specific meteorological information, including temperatures, irradiance and weather data from each of the sites.
This approach ensured that the hypothetical plants closely represented actual onsite conditions based on a typical meteorological year.
Business development manager for sub-Saharan Africa at First Solar, Laura Luckhurst explained: “The simulation was an important exercise in understanding the performance based on real world conditions and to drive the conversation away from the ‘dollar per watt’ to the more economic performance related ‘dollar per kilowatt hour.”
One technology stands out above the others
The analysis demonstrated that, in South Africa, the thin-film modules under these conditions would deliver more energy per year than poly-crystalline silicon panels and mono-crystalline silicon panels in both a fixed-tilt configuration and with the use of trackers.
The report revealed that, at the three hypothetical sites:
- Thin-filmed modules offered a 1.3% energy yield advantage over mono-crystalline silicon technology and as much as 4.2% more energy than poly-crystalline silicon panels, in a fixed-tilt configuration.
- Whereas, using single-axis trackers allowed thin-filmed modules to deliver 1.7% more energy than mono-crystalline silicon technology and 4.3% more than poly-crystalline panels.
Renewable Energy Business Leader at Arup Southern Africa Justin Wimbush said: “This research is particularly important in light of the highly competitive tariffs that we’re seeing in South Africa’s Renewable Energy Independent Power Producer Procurement Programme.”
He added: “It’s clear that every kilowatt-hour of energy is important and that selecting the right technology for a utility-scale PV Power Plant can add a significant financial upside to the project value.”