Physikalisch-Technische Bundesanstalt

In Germany, one cubic metre of natural gas was not the same thing as in the Netherlands – in any case before September 1999. For the two states determined the quantity of natural gas flowing through a pipeline by completely different methods. So – before the decisive date – it could happen that the same quantity of gas was sold at different prices – according to whether it flowed from Germany to the Netherlands or in the opposite direction. And this on a market on which gigantic quantities are traded. In Germany alone 95 billion cubic metre of natural gas per year flow through the pipeline systems to the ultimate consumer, corresponding to a monetary value of about 40 billion DM.

In September 1999, the state institutes of Germany and the Netherlands responsible for metrology – the PTB and the Nederlands Meetinstituut (NMi) - agreed that from that time on they would understand the same by one cubic metre of natural gas. This was the first cooperation agreement between two national institutes to realize a common metrological unit, in this case, the "high-pressure cubic metre of natural gas".

As a result, the disadvantage arising from the use of different methods of measurement was elegantly turned into an advantage: The two countries retain their different measuring procedures and determine a weighted mean value from their results. The measurements now are more reliable and potential differences are excluded from the start.