MADRID  - Enagas has agreed to sell its 30.2% stake in U.S. energy infrastructure company Tallgrass Energy to finance green hydrogen projects, the Spanish gas grid operator said on Wednesday.

U.S. investment firm Blackstone, which already had a stake in Tallgrass, will pay $1.1 billion for the stake, Enagas said in a statement.

Enagas expects a 360 million euro ($389.38 million) capital loss from the transaction, which is expected to close by the end of this month, it said.

Enagas paid $836 million in 2019 to take over Tallgrass with Blackstone and Singapore's GIC sovereign wealth fund. Tallgrass was later delisted.

Enagas - in which the Spanish state owns a 5% stake - aims to transition from its traditional role as a natural gas grid operator to managing a network of hydrogen infrastructure, taking advantage of the government's plans to develop green hydrogen production.

It expects net investment of around 3.2 billion euros will be required through 2030 to develop its planned hydrogen trunk network in Spain and its flagship project, the trans-European H2Med corridor.

To help fund the plan, it has slashed its dividend plans for the next three years.

By the end of the decade, the group's regulated hydrogen assets, worth some 3 billion euros, are expected to exceed those of natural gas, seen at around 2 billion euros.

($1 = 0.9246 euros)

(Reporting by Inti Landauro and Pietro Lombardi; editing by Muralikumar Anantharaman and Jason Neely)