One of the main challenges in the advancement of the renewable energy is the efficient storage of energy. Although solar energy is one of the most accessible, its storage remains a crucial challenge to achieve its mass adoption. Currently, the storage and transportation of this energy are aspects that need innovative solutions to make it more competitive in global markets.
One of the latest technological innovations has been developed by a team of researchers from the Chalmers University of Technology, in Gothenburg, Sweden. This team has shown that it is possible to store solar energy in a chemical fluid, known as molecular solar thermal systemThis breakthrough opens new doors to storing large amounts of solar energy efficiently and for long periods of time.
How does solar energy storage in a fluid work?
The key to this innovative system lies in a special fluid that, when hit by the photons of sunlight, changes its molecular structure to store energy. This process is known as isomerization, in which the fluid molecules rearrange themselves to capture solar energy in the chemical bonds of the isomers.
When the molecule rearranges, the energy remains stored latently and can be available for long periods even under normal ambient temperatures. This system is extremely robust and has been proven to withstand over 140 charge and discharge cycles without experiencing significant degradation in performance.
This type of chemical storage has advantages over conventional batteries as it can store solar energy in the form of heat and release it on demand through a catalyst, returning the molecule to its original form. This technology has shown a conversion efficiency of sunlight of up to 80 %, something considerable in the context of renewable energies.
Technological advancement: from research to practice
The fluid research project began more than six years ago and has been published in the scientific journal Energy & Environmental. In its origins, the process used ruthenium, an expensive element, and had a very low efficiency of only 0,01%. However, after years of improvements, scientists have managed to increase the efficiency to store the 1,1% of sunlight which affects the fluid as latent chemical energy.
In addition, ruthenium has been replaced by cheaper components based on carbon, hydrogen and nitrogen. This change has allowed access to a more cost-effective system, with the ability to store and release solar energy at a fraction of the initial cost. The fluid, which is based on organic compounds such as norbornadiene, is transformed when exposed to sunlight into quadricycle, a compound that stores energy in its molecular bonds.
Practical applications and system life
This storage system is attractive because the stored solar energy can be kept dormant for to 18 yearsThis means that the energy collected today could be used even in low solar radiation environments, such as winter or at night, increasing its viability for everyday applications.
Furthermore, the potential applications of this fluid are vast. Its use in fuel cell systems has been proposed. residential heating, such as in water heaters or household appliances that require a constant heat source, but also in industrial applications such as sterilization and other processes that require heat.
One of the additional advantages is that the fluid can be recharged and reused in multiple cycles, ensuring an economical and efficient system in the long term. So far, this fluid has been shown to perform more than 125 cycles without any damage being identified in its molecular structure, which is clear proof of its durability.
The future of solar storage system
The advances in this solar storage system have been recognized at the European level. In 2020, the project received a 4,3 million Euros in funding by the European Union, aimed at developing large-scale prototypes. This investment will allow progress in testing and, eventually, make these systems available for commercial use in the next 10 years.
This system not only holds great promise for the renewable energy sector, but also for the fight against climate change due to its low cost, durability and high conversion rate. In particular, the Recent advances in catalyst manufacturing They have allowed better control of the release of energy in the form of heat, improving the efficiency of the system when such energy needs to be extracted.
The progress of the aqueous electrolysis As a complementary solution, it is also gaining ground, allowing solar surpluses to be stored in the form of hydrogen, another key energy vector that is increasing in popularity due to its ability to manage fluctuations in renewable supply.
As we continue to develop and improve these types of technologies, chemical storage of solar energy in fluids could revolutionize the way we manage solar energy, providing an efficient and scalable solution to deal with the growing demand for clean, renewable energy.
With these advances, humanity could be faced with one of the most innovative solutions for storing and harnessing solar energy, not only in the home, but also in countless industrial and commercial applications.