Chinese researchers have tapped into the properties of graphene to develop new solar cells that generate energy from sunlight as well as raindrops. While less efficient compared to conventional solar cells, the new design pushes the limits of solar power production by solving the issue of inclement weather.
The clean energy from photovoltaic solar panels is inexhaustible, non-polluting and scalable. In addition to being almost completely recyclable, solar panels are suitable for the decentralized production of electricity in isolated sites. Thanks to their modularity, they are suited for installations of various sizes in different environments, from domestic to large-scale industrial implementation. However, solar cells are costly, and their manufacture has a non-negligible environmental and energy impact. Besides, they can be stimulated only by sunlight, so their efficiency drops to its lowest on cloudy days.#Chinese scientists developed all-weather solar panels coated in #graphene.Click To Tweet
All-Weather Solar Panels Coated in Graphene
A team of scientists from the Ocean University of China and Yunnan Normal University have developed solar cells able generate power even in the rain. These new all-weather solar panels are a proof of concept described in a paper published in the journal Angewandte Chemie.
To achieve this, researchers experimented with the super material graphene for its many advantages. Graphene is an excellent conductor and allows light to pass through it. They added an atom-thick layer of electron-enriched graphene to a dye-sensitized solar cell, enabling the cell to react with the ions in raindrops.
Other than water, raindrops contain salts, such as calcium, ammonium, and sodium, which dissociates into positively and negatively-charged ions. Positively charged ions bind to electrons in the graphene layer, forming a double layer (a pseudocapacitor), which facilitates the displacement of electrons at the surface of the solar cell, and thus an electric current is generated.
A Promising Solution for our Energy Crisis
With a solar-to-electric conversion rate of 6.53%, the potential of these graphene-coated all-weather solar panels seems very limited, compared to 22% conversion rate of the most efficient photovoltaic cells. Nevertheless, this new concept could guide research into all-weather solar cells of optimal efficiency–especially with the development of simple methods to mass-produce graphene.
All-Weather Solar Panels Perfect for Bavaria
Germany, for example, which produces up to 50% of its electricity needs from solar irradiation, could increase its PV capacity further. In regions like Bavaria, where it rains more than a third of the year, all-weather solar panels could increase energy capture from rooftop solar panels.
Each Bavarian resident has three to four times more the photovoltaic capacity than when compared to residents of other regions. This clean energy culture, combined with new systems of rooftop energy culture, could make Bavarians a clean energy model for the world.