The Unseen Materials Contributing to Solar Panel Success
by Rachel Morrison - Senior Research Engineer I at Saint-Gobain Research North America
Solar Panel Economics
One of the historical challenges with renewable energy is affordability, however recent strides in solar energy have made the technology much more affordable. According to the International Renewable Energy Agency (IREA), the average cost of solar panels decreased by around 82% between 2010 and 2020, going from the most expensive electricity source to the cheapest. At the rate of progress since, many believe solar power may eventually be ‘too cheap to meter.’
While solar energy alone may not solve all the challenges associated with decarbonization, it is a vital and rapidly growing component of the global effort to transition to a low-carbon and sustainable energy future. Its versatility, scalability, and environmental benefits make it a critical tool in achieving decarbonization targets and mitigating the impacts of climate change. So, the urgency around ensuring affordability and overall resilience remains critical.
In addition, relying heavily on fossil fuels for energy production increases the vulnerability of economies to fluctuations in fossil fuel prices and supply disruptions. Solar energy diversifies the energy mix and reduces dependence on finite and geopolitically sensitive resources
Behind the scenes, a variety of tech contributions play a part in the evolution of solar. In terms of material science, the role of Ethylene Tetrafluoroethylene (ETFE) is acknowledged as a crucial material for solar panel frontsheets and has gained popularity in the photovoltaic industry due to the solar panel film’s numerous advantageous properties.
Textured ETFE and Long Term Durability
Textured ETFE: ETFE can be textured, which provides an aesthetic benefit and a potential safety benefit in reducing solar glare in populated areas.
Weathering and Durability: ETFE has excellent weathering and long-term outdoor durability, being highly resistant to UV degradation and extreme temperatures. ETFE can be used for decades in outdoor applications and maintains its essential properties.
Transparency and Refractive Index
Transparency: ETFE has excellent transparency, with the capacity to outperform glass in light transmission, which can lead to an increase in solar cell efficiency.
Refractive Index: ETFE has a low refractive index, which when combined with other materials in the solar stackup can reduce optical losses due to reflection and increase the solar cell efficiency.
This lightweight, flexible material compares favorably to glass, which is typically very rigid, heavy, and reflective. Panel manufacturers need not be concerned with reinforcing a building to support the weight of solar cells. Meanwhile, alternative materials like polyester and polycarbonate perform worse in terms of weathering, transmission, and surface energy.
So while alternatives to ETFE exist, these alternatives can come with reduced performance and shorter lifetimes. Shorter lifetimes will require the solar panels to be replaced more frequently, which decreases solar’s cost advantage.
As solar energy continues to contribute to energy sector decarbonization, ETFE-based solar films in panel frontsheets is likely to a remain a highly relevant input.