Article 18 4

(a)

transmission system operators shall be required to provide the discount only for the shortest possible route in terms of border crossings between the location of where the specific proof of sustainability declaration, on the basis of a certificate referred to in the first subparagraph, was first recorded in the Union database and where it has been cancelled as considered consumed, provided that any potential auction premium is not covered by the discount;

(b)

transmission system operators shall provide the relevant regulatory authority with information on actual and expected volumes of renewable gas and low-carbon gas and the effect of applying the tariff discount on their revenue and regulatory authorities shall monitor and assess the impact of the discount on tariff stability;

(c)

once the revenue of a transmission system operator from those specific tariffs is reduced by 10 % as a result of applying the discount, the affected and all neighbouring transmission system operators shall negotiate an inter-transmission-system-operator compensation mechanism;

(d)

further details required to implement the discount for renewable gas and low-carbon gas, such as the calculation of the eligible capacity for which the discount applies and the required processes, shall be set in a network code established pursuant to Article 71.

The transmission system operators concerned shall agree on an inter-transmission-system-operator compensation mechanism within three years of their revenue from specific tariffs being reduced by 10 % as referred to in the second subparagraph, point (c), of this paragraph. Where, within that period, no agreement is reached, the relevant regulatory authorities shall decide jointly on an appropriate inter-transmission-system-operator compensation mechanism within two further years. In the absence of an agreement among the regulatory authorities, Article 6 of Regulation (EU) 2019/942 shall apply. Where the regulatory authorities are not able to reach an agreement within two years, or upon their joint request, ACER shall adopt an individual decision, in accordance with Article 6(10) of Regulation (EU) 2019/942.