DUBAI- State-controlled Saudi Electricity Company (SEC) 5110.SE , the kingdom's electric transmission monopoly, is expected to raise between $1 billion and $1.25 billion with dual-tranche green sukuk comprising five and 10-year tranches, a document showed on Thursday.

SEC set the final spreads at 140 basis points (bps) over midswaps for the five-year sukuk and 170 bps over midswaps for the 10-year tranche, tightening both by 30 bps from where it began marketing them earlier on Thursday.

It received over $5.2 billion in combined orders for the sukuk, according to the document from one of the banks arranging the deal, which is expected to close later on Thursday.

(Reporting by Yousef Saba; Editing by Jon Boyle) ((Yousef.Saba@thomsonreuters.com; +971562166204))