KTH Royal Institute of Technology

Windows could be made from transparent, renewable 'wood', according to Swedish researchers.

A team from the KTH Royal Institute of Technology in Stockholm have created what they describe as 'transparent wood', a type of veneer in which a component of the cell walls is chemically stripped. "When the lignin is removed, the wood becomes beautifully white," said Lars Berglund, who lead the research. "But because wood isn't not naturally transparent, we achieve that effect with some nanoscale tailoring."


After the cell walls are stripped, a transparent polymer is inserted into the wood, and "the optical properties of the two are matched".

The wood could be used for privacy windows, letting light in but maintaining a level of semi-transparency. But it may be most useful, as solar panels; according to a study detailing the research, which has been published in Biomacromolecules, the construction sector accounts for "around thirty to forty percent" of total energy consumption.

"It is therefore of great importance to reduce energy consumption in the building sector. Solar energy is attractive in this context since it is free, inexhaustible, and clean. Light-transmitting buildings can also contribute to reduced demand, since artificial light can be partially replaced by natural light."


The team say they are looking to "work further" with "different types of wood", and are also hoping to "enhance the transparency of the material".

material in buildings," said Berglund. "It's attractive that the material comes from renewable sources. It also offers excellent mechanical properties, including strength, toughness, low density and low thermal conductivity."

Optically transparent wood is not entirely new -- in 2009 a Japanese team detailed their creation of a "wood-cellulose nanocomposite" which they hoped would form the basis of flexible LED lighting.