Rooftop solar panels have gone through a renaissance. It is commonplace to see communities sprinkled with radiant roofs, especially as regions like California make it mandatory to include them in new builds.
The amount of solar roofing that has changed in the last decade is a monumental testament to the dedication of builders, construction professionals and environmentalists who drive renewable energy generation and funding. What are some of the most notable wins from the last 10 years so people can look forward to 10 more?
Increased Efficiency
Solar cell technology has taken several forms, and researchers have tested numerous compositions to nail down the golden formula for optimal efficiency. The National Renewable Energy Laboratory has maintained a detailed solar efficiency chart since 1988. All makers have experienced an uptick since 2015. Some reasons behind this may include bifacial panels, perovskite cells and passivated emitter rear cells.
Financing and Commercial Pricing
Rooftop solar used to be exclusive to luxury markets. However, data proves every time global capacity doubles, prices fall by around 20 percent, making it accessible to more households worldwide. New financing options manifest as prices decrease, including power purchase agreements and solar leases, alleviating fears associated with the initial investment.
Several factors are at play, but many revolve around economies of scale. Simplified manufacturing processes made them less expensive, which bred more competition and reduced prices. The trend will continue and transform other renewable energy generators, like geothermal heat pumps.
Another influence is government incentives. In the U.S., the Inflation Reduction Act provides up to 30 percent tax credits for qualifying solar technologies, making them the most affordable in history. Federal support for adoption is a dramatic change that has shifted public buy-in and stakeholder interest.
Building-Integrated Photovoltaics (BIPV)
Most people associate rooftop solar technology installations with a retrofit. The panels can work with the home, but they were not anticipating their integration during construction. BIPV has become an expectation in many places. Inventions like solar shingles make the panels look like an aesthetic, intentional part of the roofing infrastructure instead of an afterthought.
Building-integrated photovoltaic-thermal configuration (BIPV/T) is only one revolutionary idea taking the sector by storm. They warm a thermal fluid from which the panel can extract heat. They are ideal for places with limited roof space and work well with a multigeneration system, complementing other renewable energy producers.
Recycling and Sustainability Initiatives
Industry professionals have prioritized creating long-term end-of-life solutions for rooftop solar technology, primarily as the metals involved are scarce. The rarity of some has led to supply chain delays, which prohibit rapid rooftop solar expansion.
Recycling facilities have found creative solutions to reclaim materials in the last decade to make the sector more circular, notably when panels are beyond repair and need replacing. Tests have discovered ways to recycle panels with a 99 percent recovery rate. A decade ago, environmentalists lamented the nearly nonexistent recycling possibilities behind rooftop solar. Salvaging materials reduces manufacturers' emissions and environmental impact.
Decentralization and Microgrids
Installing solar is an individual choice with communitywide influence. Homeowners may only be able to generate enough solar for their house. However, regions with near-constant sunlight may produce more than they can use. Leveraging excess electricity is crucial for fully embracing sustainable ideals — nothing should go to waste. It inspired a decentralized approach to rooftop solar, in which neighborhoods separate themselves from utility providers and become self-sufficient.
Maintenance has also become more straightforward to instigate. Smart technologies, like the Internet of Things, connect to sensors to inform solar owners how well their panels are doing. They can verify electrical load assessments and see if parts are in good health to meet safety standards. It can also remind people when to schedule regular inspections and cleanings, which have become easier over the last decade with automated systems and notifications to licensed professionals.
Sharing solar energy makes the investment more affordable, primarily for lower-income communities struggling to justify their integration. It could help families earn money back through demand response programs, which have advanced in the last decade. One rooftop solar installation could supply power for several houses and energy storage in emergencies.
Energy Storage Solutions
Construction and building professionals have started embracing climate-resilient infrastructure, where materials and layouts persist despite extreme weather and natural hazards. External batteries and equipment like the Tesla Powerwall exemplify how this recent trend makes communities more confident during outages or high-use seasons. Tesla’s energy storage system in California contains hundreds of lithium-ion batteries to store 730 megawatt-hours of power for the Moss Landing area.
Improved Durability and Life Span
Solar panels used to be weaker. Now, stronger materials and more rigorous environmental testing have transformed them into rooftop fixtures capable of withstanding pelting hail and the hefty weight of sand or snow. The average life span of a rooftop solar panel can exceed 25 to 30 years — around the average time for most roof replacements.
Their ability to harness power degrades over time, but this has improved. Studies show the solar panel degradation rate ranges between 0.5-0.8 percent annually. If the panels last 25 years, they will operate at around 87.5 percent efficiency near the end of their life cycle.
The durability of peripherals, like inverters and the racking system, has also improved. Racks use corrosion-resistant steel, and inverters have laminates and coatings that protect the capacitors and transistors from conventional damage.
Panels have also become more flexible, which enhances their durability on unconventional structures. For example, thin-film technologies and organic photovoltaics make rooftop solar possible in places where rigid panels would otherwise be dangerous.
Rooftop Solar Technology Advancements
The leaps in solar roofing made in the last decade should give the industry and citizens hope for how bright the future is for the next generation. Every year, installers and engineers discover more about how to craft the perfect, lightweight and efficient panel, while communities learn how to better use them for longevity and sustainability. With the help of governments and intersector partnerships, rooftops will become the most valuable they have ever been because of renewable energy.
