A common debate among solar panel consumers is whether a mono PV module is a better choice than a multi PV module. Although mono panels were initially superior, as technology and manufacturing processes have improved, mono has caught up with multi or polycrystalline solar panels. This evening in technology and process has mad the manufacturers of both types of panels much more important.
Mono PV modules are a dark black color and the cell corners are clipped because of the production process and monocrystalline silicon. Poly PV modules are usually light or dark blue and sometimes the colors vary even within one module. The differences are in the manufacturing and production processes used for each type of module.
Traditionally, a mono PV module has a higher peak efficiency rating. Another selling point has always been that you could find a mono module more easily than poly or multi-modules. While the first is still generally true, the second has been resolved and a discerning consumer can find poly modules as easily as mono.
In a head to head matchup between two popular manufacturers of the same type models (just mono versus poly, but everything else being equal,) the mono PV module got slightly better efficiency ratings at the mid-price level than a poly PV module. That trend continued throughout higher-end models. That raises the question of whether a few percentage points is worth hinging a decision on.
Efficiency Rating and its Importance
The importance of efficiency rating comes down to space and budget. Will a few percentage points make a big difference between one, 50 or 100 panels? Obviously, the more you have the less important the efficiency rating becomes in terms of overall output.
Thus, if a solar panel owner has adequate spacing and can spend whatever is needed, efficiency might not be that big of a deal. If the owner has limited space or a tight budget, those percentage points take on an added importance. Additionally, the cost per watt will factor into any purchase decision as will the proficiency of any solar inverter that is used.
If you were hoping for a clear-cut winner, you will be disappointed. Both technologies are proven, and the differences now are largely dependent on the category panel you are buying. If efficiency rating is driving your decision, a mono PV module will serve you better. If, however, your space is large and your budget is not an issue, a poly module might work just as well.