Solar-generated energy isn’t new, but its adoption has gained significant traction since the 1970s. There are many factors driving growth across the globe, including rising interest in energy independence, renewable power and reducing greenhouse gases that contribute to climate change.
The Perfect Union: Metal Roofing and Solar Panels
According to a report published in Statista, solar technology has grown at an average annual rate of 24 percent in the U.S. over the past decade with approximately 4.4 million homes equipped with solar panels. Experts anticipate continued growth to 16.8 million homes by 2032. This trend is reflected globally; estimates from the Global Solar Council and SolarPower Europe indicate that it took 68 years to reach 1 terawatt in solar-generated energy but just two years to reach 2 terawatt in 2024*.
A significant force behind this rapid expansion is the 7 billion solar panels in use worldwide through ground-mounted systems, floating solar farms and installed on rooftops, a sizeable segment of the industry.
This exponential growth in solar roofing installations warrants consideration of the most suitable roofing material to support them.
Why Metal Roofing is the Right Choice
For both commercial and residential applications, builders, architects and homeowners are increasingly recognizing the synergy between solar panel technology and metal roofing, widely considered to be ideal due to the durability, longevity and strength of metal.
Metal roofing is engineered and warranted to last 30 years, which aligns with the lifespan of most solar panels. In contrast, traditional asphalt shingles typically last only 15 to 20 years. This requires the inconvenience and costs associated with removal and reinstallation of solar panels during roof repairs or replacements.
Metal roofs, particularly those with standing seams, offer excellent compatibility with solar panel mounting systems. Special mounting systems can securely attach the panels to metal roofs without penetrating the surface, preserving the roof’s integrity and extending its service life. In contrast, installing solar panels on asphalt shingles often requires perforating the roof, increasing the risk of leaks and potential water damage.
The strength of metal roofing is another advantage. They are robust enough to handle the weight of a solar panel system without compromising structural integrity. This strength, fortified with high-performance protective metal coatings, ensures that both the roof and the solar panels can withstand harsh environmental conditions long-term, without sacrificing aesthetics or functionality.
While asphalt shingles still account for roughly 75% of projects in the U.S., metal roofing is gaining ground due in part to the harmony with solar panels that is unmatched with asphalt shingles.
Sustainability Advantages of Metal Roofing
The longer life span of metal roofs translates to reduced material usage over time and the renewable energy generated from solar panels are both significant wins for sustainability. But there is another advantage that ups the environmental benefits—cool coating technologies.
Buildings are significant contributors to global greenhouse emissions, accounting for nearly 50% of global emissions and consuming anywhere from 25% to 40% of energy—with demand growing exponentially.
One of the most important advancements in the building and construction industry is the development of cool coatings that incorporate infrared (IR)-reflective pigments like PPG’s DURANAR® ULTRA-COOL® PVDF and DURASTAR® ULTRA-COOL® SMP coatings.
Compared to standard coatings, cool coatings have a higher degree of solar reflectance and improved thermal emittance, meaning the substrate “sheds” more sunlight and heat. The difference is significant.
A standard black pigment has a total solar reflectance (TSR) value of about 5%. But a black IR-reflective pigment reflects about 50% of infrared energy, raising the TSR value to the 25-30% range.
Commonly used on roofing, wall panels and other metal building components, these coatings help to lower building temperatures and reduce energy demands for cooling.
While cool coatings aren’t new—PPG commercialized one of the first back in 2001—continuous advancements have continued to drive up their value in terms of substrate protection, aesthetics and cooling performance.
These fade and chemical-resistant IR-reflective pigments also help to preserve the structural integrity of the metal substrate by reducing corrosion, warping, thermal expansion and polymer degradation—protection that can extend the life cycle of the metal roof.
The combination of a metal roof foundation and solar panels is a perfect union, offering significant advantages in terms of longevity, performance, energy efficiency and sustainability compared to traditional asphalt shingles.
As the world continues to adopt new ways to generate, store and utilize solar power, metal roofing will play an increasingly significant role in this evolution.
* 2 TW of solar equals the combined capacity of India, the USA, and the UK, powering roughly one billion homes. (https://www.solarpowereurope.org/press-releases/global-solar-council-announces-2-terawatt-milestone-achieved-for-solar-1)