How wood can be better utilised
Wood is the raw material of the future - sustainable, renewable and climate-friendly. But how much wood is actually available in Switzerland and how can it be optimally utilised? Researchers at Empa and WSL have comprehensively analysed the material flows of wood and show ways in which this valuable raw material can be used more efficiently and sustainably.
Switzerland is aiming for net zero by 2050. Wood plays a key role in this endeavour. It binds CO₂ from the atmosphere, is versatile and offers sustainable alternatives to fossil fuels. But how much wood is actually available for construction, industry or energy generation? Researchers from Empa and WSL have provided the answers by analysing the material flows of wood in Switzerland in detail for the first time as part of the SCENE project.
For their analysis, the researchers used data from 21 different sources for the year 2020, from wood harvesting to disposal. “In contrast to other studies, which often only use modelled values, we were able to draw on real data,” explains Nadia Malinverno from Empa. The effort paid off, as the study provides a precise picture of the entire wood flow in Switzerland.
Recycling potential and the correct use of wood
Only eight per cent of wood is currently recycled, compared to around 70 per cent for paper. In addition, 40 per cent of the wood harvested each year is used directly as fuel. “This is not ideal from an ecological point of view,” emphasises Claudia Som, co-author of the study. In order for wood to fulfil its role as a CO₂ store, it should be used as a material for as long as possible.
The researchers’ vision is cascade utilisation
Here, wood is first processed into durable products such as beams and boards that remain in the construction industry for as long as possible. Only after repeated use is the wood further processed into wood chips or fibres before it is finally burned. “Wood should only be used as an energy source when it is no longer usable as a material,” explains Som.
The path to sustainable wood flows
As part of the SCENE project, the researchers want to investigate more closely in future which uses of wood make the most ecological and economic sense. They are focussing on specific material flows. In what form is the wood available? How is it processed? Where is there potential for optimisation?
“The sustainable use of wood is a key component of the energy transition,” says Malinverno. “Our work shows that Switzerland still has many untapped opportunities here, both in terms of climate protection and resource efficiency.”