One of the most frequent questions we get asked by customers when they're considering a Solar Power system is “why
should I pay a more for quality components ?
With our commercial customers we talk about “yield security” – it’s all
about making sure that the income stream generated by the solar system
(in effect that’s what you’re buying) will continue for a long period
time. You only get that peace of mind with quality components.
Solar Panels
Cell quality – producing a solar cell is a very complex process and requires very tight quality control and superior production equipment to produce a cell that will reliably produce close to its rated power for a long time.
Example: performance is affected from the purity of molten silicon used to grow cells to roughness of wafer cutting to the uniformity of paste layers on the cells.
Build quality – after the cells there is still a matter of quality framing and encapsulation to build the panel for longevity against moisture and heat.
Example: cells inside the panel expand and contract thermally throughout the day. In high quality panels this expansion is compensated by a stress relief arch. In low quality panels this is not the case and if this thermal movement is not compensated for it cause the panels to delaminate faster compromising production.
"PID" – Potentially Induced Degradation is a leakage current from the cell to the frame of a panel that progressively worsens production from a cell. It can be stopped/minimised by applying the anti-reflective coating onto the cell in as smooth a way as possible using an accurate ratio of silicon to nitrogen, this requires very high quality control and very high quality equipment to do.
Additionally anti-pid can make use of good encapsulation with high quality materials – again a feature of high quality panels.
Solar Inverters
Build quality – the design of an inverters circuit board and the quality of the components used drastically affect the performance and longevity of an inverter. By using high quality components inside the inverter means the inverter stands a far better chance of operating to a high degree of performance and for longer than an inverter that uses cheaper internal components.
MPPT quality – the maximum power point tracker is what ensures the inverter is always producing as much power as possible. The mppt is perhaps the most important part of an inverter as it is the part that gets the most power out of panels at any point in the day.
Example: in clear sunlight a good quality mppt can allow up to 3% more production than a cheaper mppt which adds up after 25 years. In low light conditions (overcast, morning and afternoon) this production gap will be even higher. In shaded conditions due to the way a good quality mppt works vs. A poor quality one production difference may be as high as 30%.
Control software – this is how well the inverter is designed to cope with all aspects of operation such as power control, overvoltage protection, monitoring etc. And higher quality inverts mean better operation of the entire system.
