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4.2 Concrete
The concrete case is another good example of how network
governance can benefit the circular economy. Concrete is a
relatively simple product, consisting of sand, gravel and cement.
The product chain, however, encompasses a large variety of
businesses, practically all of them working in the Netherlands,
except for the cement production. The concrete sector is highly
regulated, which makes it hard to develop and implement
innovations. Commissioning parties can strongly influence the
performance of the concrete sector via their procurement policies.
The transition to more circular concrete is therefore an interplay
between the sector itself, commissioning parties, research
institutes and governments. All parties were aware of the urgent
need to reduce the environmental impact of concrete, particularly
cement. In response, they signed the Concrete Agreement
(‘Betonakkoord’). I was involved as a transition broker to formulate
the agreement in the preparatory phase and as chair during the
execution phase.
Each year, the Dutch concrete sector produces 15 million m 3
concrete, which generates about 3.7 megatons (1.7%) of the
national CO 2
emissions. Cement accounts for about 80% of
concrete production’s CO 2
emissions. Due to the high volumes of
concrete used worldwide, the cement industry is responsible for 5
to 7% of anthropogenic CO 2
emissions worldwide. Moreover, the
annual aggregate concrete production and its water consumption
lead to depletion of natural resources. To reduce this impact,
decreased use, reusing and recycling should become matters
of course. In the Netherlands, 90% of demolished concrete now
ends up as pavement under roads. More high-value recycling
and reuse are possible, but not yet commonly applied. It should
be noted, however, that more new buildings are constructed than
demolished in the Netherlands, meaning that only about 20% of
concrete used in new buildings can come from recycled materials.
Sand and gravel availability is not yet a problem. But extra efforts
should be made to guarantee that excavation does not lead to
biodiversity losses.