Monocrystalline cells (Mono) are manufactured from single silicon crystal. They have high efficiency, better low light performance and long life span owing to the fact that they are made from high quality silicon crystals. Polycrystalline (Poly), as the name implies, are from melting multiple silicon crystals. They are simple to manufacture, cost-effective and produces less wastage. However, rapid changes in cell manufacturing processes are beginning to narrow this cost advantage that poly modules enjoyed over their mono counter parts. As of 2018, mono modules account for 50% of global PV cell production. There are other cell developments like bifacial and thin film. However, the former is relatively new and the later has poor efficiency for residential applications
PERC is an innovation that is currently available in the form of Mono and Poly cells. Conventionally, solar cells have an emitter layer on the front surface and a black coating on the rear side. On the other hand, Passivated Emitter and Rear Cell (PERC) uses dielectric passivation film on the rear surface of the cells. Thus, in PERC cells, the front surface absorbs sunlight while the rear surface absorbs the scattered or reflected light. This results in higher generation than their traditional counterparts due to higher light absorption and internal reflectivity. These two factors adds multiple benefits to the end users, especially the residential consumers.
PERC modules have two significant highlights:
- Better flexibility – provides the end-users with more tilt and placement options without sacrificing efficiency – convenient for residential consumers with space restrictions on roofs.
- Higher energy density– lower levelized energy cost leads to lower payback periods.
Mono PERC Panels
When we combine two of the best technologies in the market, they provide even higher energy efficiency of upto 22% and justifies high capital expenditure of a retail solar power system. Fewer numbers of panels can attain the desired energy production. Their exceptional low-light and high-temperature performance enables more flexibility in installation and mounting. Mono PERC may not be suitable for all types of solar projects. However, they are optimal for residential rooftop installations, where faster ROI and lower installation costs are the driving factors. The increase in demand for high efficiency panels is inevitably pushing the consumers to adopt mono PERC panels. Most tier-1 module manufacturers like Trina, Q-Cells and SunTech offer them in Australia.