This fixed portion is currently estimated at approximately euros 490 million, 20 % of which would be paid in 2019 and 80 % in 2021. a further, variable portion giving rise, where applicable, to subsequent payments reflecting EDF's shortfall up to 2041 . This will be determined on the basis of market prices and EDF's 900 MW generation volumes, without Fessenheim, as established over that period .