Rotterdam studies whether sheep wool is good for insulation

This might prevent thousands of kilograms of useful material from going to waste every year

Like other cities in Europe, Rotterdam recurs to the more environmentally friendly and more traditional lawnmowing by sheep.  Sheep bring nature closer to the urban landscape and can reach places that machines cannot.

Be as it may, just like machines, sheep need “maintenance” in the form of shearing and the result in Rotterdam is the excess of thousands of kilograms of wool every year.

With consistently declining demand for sheep wool, this by-product becomes a burden and the Dutch municipality has been forced to treat it as waste. Luckily, change might be on the horizon, as local actors are investigating whether the wool from Rotterdam’s sheep would be a good material to use in home insulation.

Natural does not mean simple, at least when it comes to sheep mowing

Municipal and provincial authorities, entrepreneurs and researchers from Blue City Lab are currently investigating the insulation properties of the wool produced in the process of sheep shearing in Rotterdam. The idea belongs to city shepherd Martin Oosthoek whose herd grazes the grass in various places in the city and produces about six thousand kilos of wool annually, as the city website has informed.

Mr Oosthoek has been observing a decline of demand for sheep wool in the past two decades, coupled with the fact that there are not many places for industrial wool processing in the Netherlands. At the same time, it is too expensive to transport the material abroad and process it there, so the material often goes to waste.

In more concrete terms, each of his sheep produces 3 kilograms of wool and it costs him 3 euros per shear, he explained for AD.nl. And while there are wool buyers abroad, they are rarely willing to cover the transportation costs. This is how the wool keeps piling up before ending up in the incinerator.

Faced with the considerable costs of shearing and the significant amount of waste it creates, the shepherd approached the municipal authorities asking for a solution on how to put it to good use.

Rotterdam Circular quickly picked up the idea, as it aligns with the municipality’s sustainability objectives - to halve the amount of waste by 2030. Thus, they entrusted a designer to study the qualities of the wool and how the material can be put to good use. Apparently, these qualities also depend on the breed of sheep and the part of the sheep.

The possible benefit, other than waste prevention, is that wool, which can be used as an insulating material, could improve the energy efficiency of homes and reduce energy bills. In addition, sheep wool is considered less detrimental to the environment than other alternatives since it is very resistant.

Some challenges remain, however. There are still very few facilities for wool washing, while too large quantities of it might be needed for efficient roof insulation. This could mean that even readily available, sheep wool is still more expensive than its petroleum alternatives. Hopefully, Rotterdam will soon find a working solution.