A-si Myths, the Truth…

Myth 2: A-si panels are less efficient so they produce less energy???

Wrong again, efficiency of a solar panel, at STC, is NOT related to the actual output of energy from these panels. It is NOT the working efficiency.

STC efficiency, means the efficiency, measured at “Standard Test Conditions”. These conditions are the Exact, Perfect, Ideal, conditions, at which ONLY ‘Mono / Poly Crystalline’,silicon, panels, will give their absolute MAXIMUM output.

Special Laboratory Conditions, to suit Crystalline Silicon panels. Conditions which do NOT happen in REAL life. Giving ‘Laboratory efficiency’,
NOT ‘REAL efficiency’.

A-si and Thin Film modules, work MUCH Better, at Conditions in the REAL World – The Working Efficiency

(STC, suitable only for Crystalline Silicon panels, is still used, to measure the efficiency of Thin Film panels. These laboratory conditions are not suitable, to give a good output from A-si or Thin Film panels,so give a false impression, a Laboratory efficiency and an incorrect efficiency, for Thin Film modules.)

Here is a list of ‘STC’, compared to ‘Real Operating Conditions’, in Kuala Lumpur, Malaysia at 1pm. You can see that REAL life makes a big difference to the Annual Energy yield of PV panels




The chart above shows the STC efficiency of several makes of Solar Panel.
Note; Thin Film, A-si or Crystalline.

The Crystalline Panels show the highest efficiency at STC, which is suitable for Crystalline panels only. See the laboratory efficiency first, at the left (STC).

Note that in Hot or Tropical climates(the graph on the right), that some panels show a much higher output, measured in Kilowatt Hours, produced over each year. Average 1.1 of the Kilowatts Hours per Watts Peak. Other panels show only 0.6 of the Kilowatts Hours per Watts Peak is produced.

If you look at the types of panel, it soon becomes obvious, that ALL the higher producing panels are the A-si or Thin film type and all the lower producing panels are all Crystalline type. There is no doubt about this.

In Cold climates there is less difference between the types of PV panel. That is because neither type produces power in Winter, so their output remains the same. Only the Summer months show a higher output for all A-si panels because this is the only time power is produced in any reasonable amounts.