Balsa wood has emerged as a potential new addition to the energy mix, with Chinese scientists turning the plantation species into a thermal storage material that they said could compete with the molten salts and lab-made compounds now dominating grid-scale energy storage. That is according to new commentary in Oilprice, which identified the Yunnan composite among a small group of unconventional technologies attracting renewed interest as renewable variability drives investor confidence to its lowest point in five years.
It comes as energy demand runs directly counter to the production patterns of solar and wind generation, and the resulting mismatch is now producing record-low wholesale prices across South Australian, German, and Californian markets through 2025 and 2026. Investor confidence has eroded as a result, with clean energy adoption now under pressure at the very point grid expansion is most urgently needed.
Grid storage has become the obvious answer, with capital flowing toward batteries and pumped hydro, and a smaller heat-storage segment now drawing fresh research interest. The Yunnan composite produces 0.65 volts of electricity after dark and stores 175 kilojoules of heat per kilogram, compared with roughly 150 kilojoules per kilogram from molten salts, which have dominated industrial heat storage for two decades.
Earlier this month, Wood Central reported that the team, led by Yang Meng at Kunming University of Science and Technology, engineered balsa’s natural cell structure to produce a composite that captured 91.27 per cent of solar heat and remained performance-unchanged for 150 days of simulated outdoor exposure.
The science rebuilds the wood from the inside out, with natural lignin stripped to turn balsa into a porous scaffold before a sunlight-absorbing coating is applied to the inner walls. Stearic acid, a bio-based wax, is then loaded into the channels, where it melts in sunlight and releases the stored heat slowly, long after the sun has gone.
The Meng team described the composite as “a scalable and environmentally friendly wood-based platform for advanced solar thermal energy harvesting” in the paper published in Advanced Energy Materials, presenting the result as a manufacturing pathway rather than a laboratory finding.
Professor Lars Berglund, Research Director of the Wallenberg Wood Science Centre at KTH Royal Institute of Technology, has previously identified scalability as the central barrier for wood-based energy storage, asking how researchers move from laboratory work to industrial production. The Meng composite uses a process compatible with existing wood manufacturing, and the international energy press pickup confirms that scale is now the open question rather than feasibility.
As it stands, Ecuador supplies more than 70 per cent of global commercial balsa from six- to ten-year plantation rotations, with Papua New Guinea and Southeast Asia providing the balance. And in recent years, the species has emerged as a core material input for wind turbine blades.
For plantation forestry, the implication is that fast-growing species, long valued only for fibre or mechanical strength, now have a second commercial use: clean energy materials. Balsa producers in Ecuador and Papua New Guinea have built supply chains around wind turbine demand, and a serious solar-heat pathway would require capital and offtake arrangements the species has not previously needed.
- For further information: Meng, Y., Wu, F., Li., Xiang, Z., Luo, M., Sheng, X., & Xie, D. (2026). Interface-Engineered Wood-Based Composite Phase Change Materials Integrating Superhydrophobic, Flame-Retardant, and Antimicrobial Properties for Sustainable Solar–Electric Energy Conversion. Advanced Energy Materials. https://doi.org/10.1002/aenm.70872
