Gas quality conversion process ensures security of supply

A significant decline in domestic production levels for low calorific value gas (low CV gas) and falling low CV gas imports from the Netherlands present a key challenge to be tackled in the coming years. In view of this background the German gas transmission system operators (TSOs) are further developing the high CV gas infrastructure to offset the dwindling low CV gas supplies. A detailed roadmap for the switchover process required to permanently convert supply areas currently receiving low CV gas to high CV quality is provided in the Gas Network Development Plan (NDP) as well as in the TSOs’ implementation report on the NDP. In producing this roadmap the TSOs contribute to a secure supply of natural gas.

In addition, the TSOs publish an overview of all switchover areas that have already been announced including information on the anticipated switchover months.


Parts of the German gas market are supplied with natural gas of the low calorific value group, all of which comes from German and Dutch production sources. All other supply sources available in Germany (such as imports from Denmark, Norway/North Sea, Russia and LNG terminals) deliver gas of high calorific value quality (high CV gas). For technical reasons as well as due to weights and measures regulations, the two gas qualities have to be transported in separate systems within defined ranges. Customers receiving one type of gas cannot switch over to gas of the other quality unless their gas appliances are adjusted to comply with the calorific value range of that other gas type.

The production capacity for low CV gas in Germany is decreasing. From October 2020 onwards both export capacity and volumes from the Netherlands will also be continuously reduced, as has been announced by the Dutch TSO GTS.

In order to meet this decline in the availability of low CV gas supplies the areas currently supplied with low CV gas are to be switched over to high CV quality. To this end the TSOs have developed a switchover concept which they are continuously working to update in cooperation with the distribution system operators involved. As part of the planning process the supply situation for low CV gas is analysed and assessed against demand.

The conversion planning process

The currently planned switchover works are described in the Implementation Report on the Draft 2018-2028 Gas NDP, which has recently been published. The planning information provided includes:

  • Low CV Gas capacity and supply/demand balances for Germany as a whole as well as for each market area taking into account the local conditions until 2030
  • Overview of the year by year low CV supply areas planned to be switched over
  • Maps of the planned switchover areas
  • Number of gas appliances to be modified by 2030
  • Cumulated number of gas appliances to be modified by 2030

A detailed list of all relevant system points including information about the switchover areas they have been assigned to and the applicable switchover timing is provided in the Gas NDP database (

Announced conversion areas

The table provided here, which is current as at 01 April 2019, lists all switchover areas for which binding plans have been announced and which are updated by the TSOs on a quarterly basis. You can also find information about interdependencies existing between individual switchover areas and the months currently planned for the technical implementation of the switchover.

Gas quality conversion charge

According to section 19a of the German Energy Industry Act (EnWG), all costs a network operator incurs to permanently convert its network from low CV to high CV quality, insofar as the measures are technically necessary, are passed on to all other networks in Germany.

The switchover costs are then recovered by the TSOs, who levy an additional unit-based gas quality switchover charge (the so-called “unit switchover pass-through amount”) on top of their usual exit tariffs.

Further informationen

For more information on the gas quality conversion process please follow the links below:

Agreement on Cooperation between Operators of German Gas Supply Networks

BDEW guideline gas quality conversion process

Information DVGW