‘Stone was a past, steel is present, and wood will be the future.’
Wood Solutions Fair at The International Centre in Mississauga, Ontario, Canada recently recognised wood as an ‘untapped natural resource.’ It was the Canadian Wood Council (CWC) that identified six wood systems to have the capacity to compete with concrete and steel. These systems include three light-wood frames and three mass timber systems.
According to scientists, wood can be transformed into a stronger material than steel using an easy and inexpensive process. In fact, it could be made stronger than high-tech titanium alloys. And therefore, wood could even be used to create armour plates that are resistant to bullets.
CWC came to the conclusion using data from working organisations consisting of engineers, architects, builders, product suppliers, developers and stakeholders. Research shows that low rise commercial construction in Canada can hugely benefit from the wood sector. In fact, innovative timber is already being used in building tall towers. More essentially, studies also reveal that people working in offices made of wood structures are healthier and happier.
Research on wood is progressing rapidly. Scientists have come up with an upgraded version of wood called the ‘transparent wood.’ Deemed as the supermaterial for the sustainable future of smart cities, we move ahead to explore its reality!
What Is Transparent Wood?
Yes, what you are thinking is true! Wood that grows on trees can actually turn transparent. The material can have up to 90% transparency and upgraded mechanical properties compared to the raw, undisturbed wood.
Transparent wood was created for the first time in 1992. The material is made by treating and compressing wood strips. In the process, lignin (the substance that makes up cell walls) is substituted by polymers to make it transparent.
Timothée Boitouzet studied architecture in Japan where wood is extensively used in buildings to fight earthquakes. Here he discovered the potential of wood. This inspired him to establish his own material science company Woodoo in Paris in 2016. Today, the company retrofits timber to enhance its physical and chemical properties.
Boitouzet’s focus is on replacing steel with wood, in the construction industry. One of the reasons is that acquiring steel as a material is a meticulous and expensive process. However, the case with wood is different. The construction industry can largely reduce its carbon footprint by just growing more trees. This will not just compensate for the wood they are using but also combat climate change.
Recently, the World Building Council found out that 11% of global carbon emissions come from materials and construction processes. The impact happens as long as the building lives. And as trees are being the storage tanks of carbon, using wood in construction means keeping carbon trapped.
Wood Can Be Applied To More Than Just Support Pillars
As per Boitouzet, wood has numerous applications in construction apart from being used as support pillars. Its because the upgraded wood is five times stronger, weather-proof and more fire-resistant.
The optical properties of the polymer are matched with that of wood. With this, light does not bend when it passes through the wood. This transparent nature of wood opens up a new world of applications.
Until now, Woodoo has most of the attraction from the automotive industry. With the initiation of a project called Woodoo Augmented Wood, the company is working on equipping electronics with the touch-sensitive wood. The transparent material, through which light penetrates will be shaped into wooden panels. These wooden panels will be used for ‘tactile dashboards’ in cars.
The company claims that the new version of the wood is lighter and generates fewer emissions than traditional panels.
With the transparency wood offers, it is likely that in future, the material replaces glass in windows. The wood used in windows can be beneficial in several aspects. For instance, it shows high heat-retaining capabilities which could help control the temperature of buildings.
Céline Montanari and colleagues at the KTH Royal Institute of Technology in Sweden advanced with the previous process of transparent wood. The team immersed lignin-free wood in polyethylene glycol (PEG). This is a polymer found in theatre smoke machines and toothpaste. When PEG-based wood is used in window panels, it traps more heat. Although this wood is not a good insulator as the natural wood, it is almost four times better than high-end double glazing. Moreover, it is biodegradable and strong enough to sustain heavy loads. When the sun is out, the material will absorb heat and keep the indoors cooler than outside. And during the night this heat is released indoors to maintain a constant temperature.
Lars Bergland, a professor in wood and wood composites at the KTH Royal Institute of Technology in Sweden has explored multiple uses of transparent wood. For him, one of the most exciting applications is embedding quantum dots in wood to design LEDs. The concept is that the ceiling would be of the wood panel which will have this LED function. In simple words, one can have indoor lighting directly from the ceiling.
The wood’s LED light is different from conventional ones as it is diffuse, more natural and soft on the eye. WoodNano Tech, Prof Bergland’s project has devised such panels out of transparent wood among many other applications. Advancing ahead, this wood may also support the development of electrochromic windows. These windows are coated with a thin skin of polymer. So when electricity passes through them, they can block out light.
As per Prof. Berglund, his transparent wood also has application in the energy sector. Using a phase-change material instead of a polymer (in the place of lignin) can transform the wood into an energy storage device. During the day, it absorbs heat and at night as temperature drops, the phase-change material crystallises, releasing heat.
However, this kind of advancement in wood technology is hindered due to scalability challenges. Prof. Berglund is seeking commercial partnership for the same.
Currently, Professor and his team are working on making the material more sustainable. The idea behind this is to retain as much of lignin as possible, instead of dumping it. Until now, they have been using petroleum-based polymers but now they are exploring ways to use bio-based polymer. Producing better wood with more environmental features can help cities construct more sustainable buildings. Transparent wood has the potential to become the most sustainable building material in the future.
Timber To Be The Building Material Of Google’s Smart City
Google’s most awaited smart city project, in the Quayside area of Toronto, will have a timber neighbourhood. Sidewalk Labs, the unit of Google’s parent company Alphabet proposed the use of mass timber as the building material. In the effort of improving the quality of life in the city using technological solutions, the company is planning to source local wood products. With this recent announcement, the company highlighted the benefits of mass timber which are as follows:
- Reduced carbon footprint
- Strong and shatterproof
- Enhanced affordability
- Low construction cost
- Flexible modular design
An entire neighbourhood built of wood will demonstrate a pioneering example of sustainable construction in smart cities. Besides, it will serve as a counteraction in the wake of global warming and climate change.
The claimed applications of transparent wood in buildings will pave the way for transforming opportunities in the construction industry. Evidently, widespread use would decrease the carbon emissions from buildings – which is globally estimated to be nearly 40%.