Spanish gas grid operator Enagas SA (<a href="https://www.bolsasymercados.es/bme-exchange/en/Prices-and-Markets/Shares/Main-Market/Details/Enagas-ES0130960018" target="_blank">BME:ENG</a>) has struck a deal to sell its stake in US energy infrastructure company Tallgrass Energy to a unit of investment firm Blackstone (<a href="https://www.nyse.com/quote/XNYS:BX" target="_blank">NYSE:BX</a>) in a push to secure capital to advance its green hydrogen plans.