Transparent wood is a material that could be used in the construction of houses with greater energy efficiency. It is also an alternative to plastic, glass and cement because it lets the light through and keeps the heat.
Common wood is composed, among other substances, of lignin, what gives color to the wood and allows it to absorb light. If we remove that lignin from the wood, it loses its brown color and turns white.
After removing the lignin, the holes are filled with a material that has the same index of refraction of the wood and it becomes transparent.
Using this material in construction is achieved, not only allow more light to enter, which reduces the use of artificial light but also, achieve greater energy efficiency because transparent wood is much better insulating than glass.
Source: theguardian.com, read original article
https://www.theguardian.com/environment/2019/apr/03/scientists-invent-transparent-wood-in-search-for-eco-friendly-building-material
