
MOST MODERN SOLAR PANELS HAVE A 3% NEGATIVE TOLERANCE RATING AND THE HIGHER THIS NUMBER, THE LOWER THE AMOUNT OF POWER THAT A SOLAR PANEL HAS THE CHANCE OF PRODUCING.
HERE'S SOME EXAMPLES:
Sharp®
Solar Panels
have a poorer 5% negative tolerance rating when compared to 3% or better solar
panel brands which means that one of their 230 Watt solar panels stands a chance
of producing only 218.5 Watts new, right out of the box, even though you paid
for 230 Watts.
SunPower® Solar Also offers a poorer 5% negative tolerance rating on their 200 to 230 watt solar panels when compared to 3% or better solar panel brands which again means for a 230 Watt solar panel that you might only receive a 218.5 solar panel even though you were expecting 230 Watts.
LOOK AT WHAT HAPPENS WHEN YOU MIX A 230 WATT SOLAR PANEL WITH A 5% NEGATIVE TOLERANCE RATING THAT RESULTS IN A 218.5 WATT OUTPUT WITH A CHAIN OF (9) TRUE 230 WATT PANELS.

So even though you might have 10, 12, 15 or more solar panels in the same chain that are producing the correct amount of power, if you add in just one poorer tolerance panel, it will pull the whole chain down. Even if you add in solar panels that produce more than their nameplate rating it won't make a difference with a weaker panel in a series chain.
Why take the risk of shortchanging yourself. The simple rule to remember is the higher the negative tolerance number the higher the chance of getting less power out of your solar array. Always insist on solar panels with a 3% or lower negative tolerance rating.
At Solar Home We Only Offer Solar Panels With A 3% Or Better Negative Tolerance Rating. That Other Solar Dealer ?....... Better Ask !