In an era of glass and steel construction, wood may seem old-school. But researchers are currently saying its time to give timber a makeover and bring to use a material that is able to store and release heat.

Transparent wood could be the construction material of choice for eco-friendly houses of the future, after researchers have now created an even more energy efficient version that not only transmits light but also absorbs and releases heat, potentially saving on energy bills.

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Originally posted by dinsintegration

Researchers from KTH Royal Institute of Technology in Stockholm reported in 2019 that they would add polymer polyethylene glycol (PEG) to the formulation to stabilise the wood.

PEG can go really deep into the wood cells and store and release heat. Known as a phase change material, PEG is a solid that melts at 80°F – storing energy in the process. This process reverses at night when the PEG re-solidifies, turning the window glass opaque and releasing heat to maintain a constant temperature in the house.

Transparent wood for windows and green architecture. Video: Wise Wanderer

In principle, a whole house could be made from the wooden window glass, which is due to the property of PEG. The windows could be adapted for different climates by simply tailoring the molecular weight of the PEG, to raise or lower its melting temperature depending on the location.