Link: https://arstechnica.com/science/2026/02/dna-inspired-molecule-breaks-records-for-storing-solar-heat/

They engineered this molecule to reliably fold into a Dewar isomer under sunlight and then unfold on command. The result was a rechargeable fuel that could absorb the energy when exposed to sunlight, release it when needed, and return to a “relaxed” state where it’s ready to be charged up again.

Previous attempts at MOST systems have struggled to compete with Li-ion batteries. Norbornadiene, one of the best-studied candidates, tops out at around 0.97 MJ/kg. Another contender, azaborinine, manages only 0.65 MJ/kg. They may be scientifically interesting, but they are not going to heat your house.

Nguyen’s pyrimidone-based system blew those numbers out of the water. The researchers achieved an energy storage density of 1.65 MJ/kg—nearly double the capacity of Li-ion batteries and substantially higher than any previous MOST material.

Only downside is the fuel costs a billion dollars per litre, or it gives everyone cancer, or it lasts 1 day?

Not being hazardous is actually one of its benefits.

Major downside is it needs an acid catalyst to release the energy, you're looking for how to simplify separating the acid later.

Research stage, so no claims about cost.

This is the second time I've hears about this tech, hopefully it goes somewhere.