First Solar has published research suggesting its CdTe thin-film modules would offer a higher energy yield than those based on crystalline silicon technology in the hot, arid conditions typical of South Africa.

Research carried out by consultancy Arup on behalf of First Solar found that that the company’s modules could offer up to a 4% higher energy yield than c-Si modules in a South African setting.

The study modelled the energy yield from First Solar modules and three other multi- and mono-Si products from “top tier” producers at three hypothetical utility-scale plants at sites in Bloemfontein, Upington and Vryburg, South Africa.

Using various modelling techniques based on site-specific meteorological data, the Arup engineers carried out 24 yield simulations to establish how the modules would perform in their first year of production at the sites.  

According to Arup’s analysis, the First Solar modules 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.

In a fixed-tilt configuration, First Solar modules offered a 1.3% energy yield advantage over mono-crystalline panels, while for multi-crystalline technology the advantage was 4.2%. Those numbers rose to 1.7% and 4.3% respectively on a single-axis tracker system.

“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. 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,” said Justin Wimbush, renewable energy business leader at Arup Southern Africa.

“The results of this extensive analysis validate the suitability and superiority of our module technology in realworld conditions, here in South Africa. It also makes the case for the solar industry to move away from legacy metrics, such as nameplate capacity, and to focus on what truly matters, which is energy,” added Nasim Khan, vice president for First Solar in Africa.

However, the study did not model the levelised cost of electricity (LCOE) of the hypothetical plants using the various modules. By using a combination of factors rather than just energy yield to calculate the per-unit cost of energy from a given power plant, LCOE is regarded as the most useful metric in establishing the performance of a plant over its lifetime.

A First Solar spokesman said: "The intent was to showcase the energy yield advantage that we can offer in actual operating conditions in South Africa. The levelised cost of electricity was not part of the study."