This New Solar Molecule Stores Sunlight and Can Boil Water Hours Later
Solar panels are great at turning sunlight into electricity, but they have one major weakness: when the sun goes down, the power stops. Storing that energy usually means connecting to large, expensive battery systems. Now, scientists at UC Santa Barbara think they have found a smarter solution — and it fits inside a liquid. Their newly engineered molecule soaks up sunlight, holds onto that energy for a remarkably long time, and releases it as heat whenever it is needed, even hours or days after the sun has set.
The key player in this discovery is a molecule called pyrimidone — pronounced pie-RIM-ih-dohn. A molecule is an incredibly tiny cluster of atoms bonded together, and this particular one was inspired by something you might not expect: DNA. DNA is the genetic material inside every living cell that carries instructions for how organisms grow and function. A part of DNA can change shape when hit by ultraviolet light and then change back again, and the researchers borrowed that same reversible trick for their invention. By engineering a synthetic, or human-made, version of a similar structure, they built a molecule that could do the same thing — absorb sunlight, shift into a high-energy shape, and hold that shape until triggered to release the energy.
Think of it like a mousetrap. When you set a mousetrap, you press the spring down and lock it in place. It stores that mechanical energy until something triggers it to snap. The solar molecule works the same way — sunlight sets the spring, and a small amount of heat or a catalyst, which is a substance that speeds up a chemical reaction, triggers the release. When it snaps back to its original shape, it gives off heat. The researchers demonstrated that this heat release was powerful enough to boil water under normal, everyday conditions, which lead researcher Han Nguyen described as "a big achievement" because boiling water requires a significant amount of energy.
The energy density of the new material — meaning how much energy it can pack into each kilogram — is also impressive. The molecule stores more than 1.6 megajoules of energy per kilogram. For comparison, a standard lithium-ion battery, the kind found in phones and laptops, stores about 0.9 megajoules per kilogram. That means this new material stores roughly 78 percent more energy for the same weight. The molecule is also deliberately compact and lightweight because the team stripped away every part of its structure that was not absolutely necessary.
One of the most practical ideas from the research team involves rooftop systems where the liquid molecule circulates through solar collectors during the day, absorbing sunlight, and then flows into storage tanks at night where the energy can be released as heat for warming water or homes. Because the material dissolves in water and can be reused over and over again, it is also designed with sustainability in mind. Co-author Benjamin Baker, a doctoral student on the project, put it simply: "With molecular solar thermal energy storage, the material itself is able to store that energy from sunlight." While the technology is still in the research stage, it represents a genuinely new direction for clean, renewable energy storage.
Source: ScienceDaily