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The opposite of throwaway
The decision to build stainless steel kilns was initially the result of classic Swedish engineering. Professional pride gave rise to robust designs that were able to withstand the changing seasons and deliver the right quality – year after year. We now know that they are also sustainable in many other respects.
There are no TV repairmen anymore. At least not of the type that anyone who was around in the 1980s might remember. The ones we naturally visited in the event of a malfunction in the aerial or picture tube. The faults were usually minor in nature, and simple remedies meant that a 24-inch TV in the living room could go on almost indefinitely. They were fundamentally solid.
Nowadays they have been replaced by electronics produced under price pressure, where the way we handle them is characterized by a throwaway mentality. As soon as anything breaks, we are expected to buy a new one.
Of course, lumber kilns represent a different challenge – neither the product nor the failure rate have much in common with old electronics. But there are similarities when it comes to the mindset. The things Valutec stands for have more in common with the old-fashioned ways of both producing and looking after your possessions.
A well-maintained kiln from Valutec, properly maintained, can achieve a service life that is longer than an entire working life.
Long experience of development
The company that now goes by the name of Valutec built its first lumber kiln in 1970. The kiln was brick-built, equipped with sliding doors and wet-bulb and dry-bulb temperature control. This represented a major advance, and attracted visitors from near and far.
It was the first step on a journey, with sealed and robust kiln structures being a cornerstone. This made it possible to achieve the high air velocities and heat that are prerequisites for being able to dry with the right level of quality.
Long service life reduces climate impact
One of the material choices that was made at an early stage in order to achieve the correct seal, particularly in our Nordic climate, was to build in stainless steel. It is now clear that the benefits are not restricted to drying quality and service life – on the contrary, calculations show that the structure’s climate footprint is also reduced by as much as 65 per cent, compared to alternatives made from aluminium.
The main reasons for this are the longer service life of steel and the fact that Valutec uses a high proportion of recycled steel in its structures.
Lumber kilns made of stainless steel kiln have a service life of at least 40 years – twice that of kilns made from aluminium. A specific example: when 50 per cent of the steel is recycled, the climate impact of building an FB continuous kiln amounts to 309 tonnes of carbon dioxide.
With a service life of 40 years, this results in an annual carbon footprint of approximately 8 tonnes. The same calculation for an alternative made from aluminium produces an annual load of approximately 23 tonnes. This difference is roughly equivalent to the amount of CO2 sequestered by two hectares of coniferous forest.*
The ability of lumber to bind carbon also means that once just over 400 cubic meters of wood products have passed through the kiln, they will have climate-compensated for its construction.
Efficient motors save energy
Valutec has also continuously improved the machinery in its lumber kilns. One of the latest advances relates to new motors, which have greatly improved efficiency. One extensive, long-term test has demonstrated that the new motors provide annual savings of just over 7,000 kWh in normal operation, compared with the motors that were previously standard in the lumber kilns. The service life of the new motors is also expected to be more than twice as long.
This means savings in terms of both money and the climate. When less energy is used, the climate impact is also reduced. The motors achieve efficiency class IE5, which is the highest level in the EU’s rating system regarding the energy efficiency of electric motors. For lumber kilns, IE2 and IE3 are the approved and commonly used levels today.
The motors’ greater energy efficiency also means that they reach significantly lower temperatures during operation, which reduces wear and increases their service life. The logging of bearing and winding temperatures shows that the temperatures reached are approximately 20°C lower.
Considering that a 10°C lower temperature is expected to double the service life of a motor, the new motors can be used for two to four times longer than a motor that meets the requirements for IE2. The motors are also the same size, which means that it is easy to upgrade existing kilns with the new motors.
This is fully in line with the first assertion in this text – the opposite of throwaway.
* Based on figures from Stena Recycling, where 50% recycled material is used in both the steel and the aluminium alternatives.
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