English to Russian Other Energy / Power Generation

Как перевести "grandfathering" в следующих контекстах?

1) The first option is to introduce an Emissions performance standard of 450gCO2/kWh with grandfathering of the level for 30 years, which is the expected operational life of a CCGT plant.

2)Grandfathering - in the context of the Emissions Performance Standar is the ability to allow some activities or former rights to continue even though they would not technically be allowed under current conditions. In the context of the Renewables Obligation it is the policy intention that once accredited the level of support generators receive does not change for the period of time that they are eligible to receive the RO.

Спасибо.