While we have been capable of harnessing the energy of the sun for immediate use. However, before solar can replace fossil fuels and other less safe sources of energy, there needs to be a way to store that energy for later use.
Researchers at Chalmers University of Technology in Gothenburg, Sweden, are working on just that. They have developed a chemical solution to store solar energy, which can then be turned into heat on command, without destroying the medium in which it’s stored. They refer to it as a molecular solar thermal system.
The process is based on the organic compound called norbornadine, that when exposed to light converts into quadricyclone.
“The technique means that we can store the solar energy in chemical boonds and release the energy as heat whenever we need it,” said Professor Kasper Moth-Poulsen, who is leading the research team. “Combining the chemical energy storage with water heating solar panels enables a conversion of more than 80 percent of the incoming sunlight.”
When the research team held its first conceptual demonstration of the technique in 2013, they were able to convert a mere 0.01 percent of solar energy into stored energy that could be transported elsewhere. They were also using an element called ruthenium, which was very expensive. Now, they have improved that storage capacity to 1.1 percent. This may not sound like much, but it’s 100 times more effective than previous technology. The ruthenium has also been replaced by cheaper carbon-based elements.
“We saw an opportunity to develop molecules that make the process much more efficient,” said Moth-Poulsen. “At the same time, we were demonstrating a robust system that can sustain more than 140 energy storage and release cycles with negligible degradation.”
As the team continues to develop this technology, we hope to see simultaneous improvement in solar energy harvesting techniques—both of which could contribute to a higher degree of use for solar products.