The performance of solar panels is determined not only by the panels themselves, but largely by the surface on which they are installed. A black roof absorbs sunlight and can become 40 to 50°C hotter than the outside temperature on sunny days. That heat radiates directly to your panels — measurably reducing their output.
Monofacial solar panels: temperature as a yield killer
Standard monofacial solar panels reach their highest yield at low ambient temperatures. According to Milieu Centraal, every 10°C rise in temperature results in roughly 5% less power output. On a conventional black roof, that difference can add up to 15% in lost yield over the year.
A Cool Roof with GE Enduris silicone roof coating reflects 88% of sunlight (SRI 111), keeping the roof surface only 5 to 10°C above the outside temperature — instead of 40 to 50°C with a black roof. The result: your monofacial panels operate at structurally lower temperatures and deliver demonstrably more energy. Added benefit: lower thermal load extends the lifespan of the panels themselves.
Bifacial solar panels: maximum yield through high albedo
Bifacial solar panels capture light on both sides — the back side also benefits from light reflected off the roof surface. That makes the color and reflectivity of your roof a direct performance factor. On a black roof with low albedo, almost all light is absorbed and lost as heat. On a white Cool Roof, much of that light bounces back to the underside of the panels.
Research from TNO and LG Energy confirms it: bifacial panels perform best on high-albedo roofs. The combination of lower temperature and more reflected light produces a double yield benefit that cannot be achieved any other way.
TNO-proven: up to 17% yield gain with CRC-PV-3502
On behalf of Cool Roof Coatings, TNO tested the specially developed CRC-PV-3502 silicone roof coating for PV yield improvement. The results are unambiguous: bifacial PV systems on the CRC-PV-3502 coating achieve yield gains of 15% to 17% compared to installation on black, low-albedo roofs.
These are not theoretical projections, but measured results under controlled test conditions by an independent research institute. For property owners and facility managers investing in solar energy, this means a substantially shorter payback period — without modifying the PV installation itself.
The hidden cost: lost yield on black roofs
Many commercial buildings have aging, dark roof coverings that are not only maintenance-prone but actively reduce the yield of increasingly common solar panel installations. Roof renovation with GE Enduris combines three benefits in a single intervention: a watertight, seamless roof skin with a 40+ year lifespan, a Cool Roof effect that reduces cooling load by up to 35%, and an optimized surface for maximum PV yield.
The CRC-PV-3502 coating is airless-sprayed over the existing roof covering — no demolition, no open flame, no business interruption. The result is a fully circular roofing solution based on silica (quartz sand), which at end of life leaves behind nothing but sand and lime upon recycling.
