The emissions of an average low-emission barn are twice as high as those stated by the manufacturer (and approved by RVO) should be. RIVM employees said this during a technical briefing in the House of Representatives.
When calculating the nitrogen emissions from stables, the RIVM therefore does not work with the emission value according to the so-called RAV list, but with its own calculation method. "Depending on the type of stable, the actual emission can be a factor of 1,1 to 3,8 higher than stated. On average it is a factor of 2," says researcher Margreet van Zanten. The RIVM is thus applying a kind of practice correction, it was stated.
40.000 stable locations
The RIVM says it has emission data from 40.000 stable locations in its system. The emissions and precise location of the stables are calculated based on the UBN number, plus the data from the combined statement, I&R data and the statement for EU payments.
When asked in Parliament, fellow researcher Kees van Luijk stated that the RIVM has a reasonably good overview of the emissions situation in the Netherlands, even though mistakes have been made in drawing up a top 100 of the largest ammonia emitters.
Emission and deposition
During the briefing it was not always clear when it was about emissions and when about deposition. The RIVM also said that - with the help of models - it is possible to measure and allocate emissions from industry and traffic. According to him, this is not possible for agriculture, but deposition should be the basis.
Members of Parliament reacted with surprise at the RIVM's statements about low-emission stables. Especially because the judge even post questions on the actual emissions from low-emission stables and states that it is not possible to rely solely on the data provided by the manufacturer. Member of Parliament Thom van Campen (VVD) wondered whether - if the data from the RAV list cannot be used for the granting of permits - it would not be possible to look at the practical figures as used by the RIVM.