Solar panels have become increasingly popular as a clean and renewable energy source. But how do they actually work? Understanding the technology behind solar panels and staying informed about the latest advancements allows a confident and informed investment decision. With that in mind, here is a dive into the science behind the technology.
How do solar PV modules work?
The light from the sun is made up of many different wavelengths. Of this light, only to the human eye. All light, even light outside the 42 to 43 per cent of light that is visible to the human eye, is composed of photons. Solar panels work by converting these photons into electricity.
Most solar panels are made and designed of materials that convert primarily visible light, because it is the majority of the light that reaches the Earth and has a higher energy concentration than infrared light.
See also: 3-million-euro investment in production of LSG interlayers in Italy
The shorter the wavelength, the more energetic the radiation and the greater the potential for harm. Ultraviolet (UV) light that reaches the Earth’s surface is in wavelengths between 290 and 400 nanometres (nm). This is shorter than wavelengths of visible light, which are 400 to 700 nm. Little to no radiation below 290 nm can reach the Earth’s surface, therefore it is not useful to maximize the light uptake in the cells at UV cut-off below 290 nm for PV modules that are installed on Earth.
The photons from different types of light have different energy concentrations. Photons from UV light have too much energy and a lot of this energy is wasted as heat. This heat warms and damages PV panels, which decreases their efficiency in the long term and deteriorates their performance over time.
UV radiation is also well known for degradating polymeric materials, as used for encapsulation of PV cells. In the PV industry, solar encapsulants are divided into UV cutting and UV transmitting films. UV cutting films have typical UV cut off at 360 nm, while UV transmitting films can transmit UV light from 290 to 300 nm.
During the last 10 years, the issue of UVID (UV Induced Degradation) has been addressed by developing the UV conversion technology, instead of the standard UV-transmission or UV-cutting technology.
The latest efficient encapsulant solution
Advanced technologies on the market are targeting the UV conversion technology: converting damaging UV light into visible blue light, thereby also boosting energy generation: The majority of deep UV photons (290 to 380 nm) are not absorbed or transmitted, but they are transformed into visible light (400 to 550 nm), thereby improving the spectral response of photovoltaic cells and resulting in higher power generation compared to UV-transmissive or UV-cutting films. This conversion process is achieved without compromising module reliability, as this technology offers reliable performance to weathering exposure.
Also interesting: How Schüco Integrates PV into the Facade of the “Matchbox” building
The photoconversion film employs a highly innovative down-conversion mechanism to switch deep ultraviolet radiation into visible light within the 400 to 550 nm range, resulting in increased power generation from photovoltaic modules.
Unlike traditional encapsulants, that exhibit accelerated degradation when exposed to prolonged UV radiation, especially in high-humidity environments, photoconversion films boast impressive long-term performance against UVID (UV-induced degradation), with minimal degradation in peel strength. Indeed, they can provide cross-linking rates over 90%, high adhesion levels, resistance to potential induced degradation (PID), low corrosion and UV stability.
Photoconversion film technology is specifically engineered to safeguard PV modules from the detrimental effects of UV radiation. Furthermore, it actively improves module performance by transforming harmful UV light into energy-enhancing light, differently from other products that can just transmit or cut UV radiation.
It is always very important to consider the degradation effects of UV light in a solar PV module and Satinal strongly suggests relying on experienced supplier of PV encapsulants rather than on experimental products.
