Store Solar Energy for Months, Release Heat on Demand
▼ Summary
– Heating represents nearly half of global energy demand, with two-thirds currently supplied by fossil fuels.
– Storing solar heat long-term is a major challenge, unlike the more advanced storage of solar electricity in batteries.
– Molecular solar thermal (MOST) energy storage aims to trap heat in chemical bonds for later release but has historically underperformed.
– Researchers have drawn inspiration from DNA damage caused by UV light, specifically the formation and repair of (6-4) lesions and Dewar isomers.
– The team’s breakthrough involves using a chemical reaction similar to this DNA process to potentially create a more effective MOST system.
Heating represents a massive portion of global energy consumption, with a significant majority still reliant on fossil fuels. Solar power offers a promising alternative, yet a major hurdle remains: while we can store solar electricity in batteries, storing solar heat for extended periods has proven far more difficult. This challenge is central to reducing our carbon footprint in heating applications, from industrial processes to residential warmth. A novel chemical approach, drawing an unexpected parallel to human biology, may finally provide a viable solution.
The concept, known as molecular solar thermal (MOST) energy storage, involves capturing solar energy within the chemical bonds of special molecules. These molecules can later release that stored energy as heat when triggered. For decades, the promise of MOST systems has been hampered by practical problems. Previous candidate molecules suffered from low energy density, rapid degradation, or a reliance on hazardous and impractical solvents.
A collaborative research effort has now demonstrated a potential breakthrough. The team took inspiration from a surprisingly familiar source: the genetic damage caused by a sunburn. When ultraviolet light from the sun strikes skin, it can cause adjacent thymine bases in DNA to fuse, creating a problematic structure called a (6-4) lesion. Further UV exposure twists this lesion into an even more distorted shape known as a Dewar isomer. In biological terms, this is damaging; these kinks in the DNA helix can disrupt replication and lead to mutations.
Nature, however, evolved a repair mechanism. A specific enzyme called photolyase seeks out these (6-4) lesions and efficiently converts them back into their original, stable form. The researchers realized this photochemical reaction, storing energy in a molecular twist and releasing it upon reversal, could be the blueprint for a new energy storage system. By designing synthetic molecules that mimic this DNA damage-and-repair cycle, they aim to create a material that stores solar energy as molecular strain and releases usable heat on demand.
(Source: Ars Technica)