It is thought the sale of up to 49 per cent of the network could raise between £1 billion and £1.5bn for the Spanish company, which has an estimated net debt of €29.3bn (£23.3bn).
Infrastructure and sovereign wealth funds are thought to be among the potential buyers of the equity stake. ScottishPower’s grid is valued at about £4.5bn.
Ignacio Galan, Iberdrola’s chairman and chief executive, met Chancellor George Osborne this week to confirm the company’s commitment to investing £8bn in its energy transmission infrastructure. He called for electricity market reforms to be finalised as soon as possible but praised the UK’s “predictable” and “stable” regulation.
Reports this week have suggested Madrid-based Iberdrola is planning the sale of a “non-core” portfolio of wind farms in Poland, as the country moves to update its renewable energy regulations in favour of offshore wind.
Iberdrola has joined a host of Spanish firms that have raised hundreds of millions on the corporate bond market, taking advantage of a fall in interest rates after the European Central Bank pledged to reduce the country’s financing costs. Earlier this month Iberdrola sold €750 million in an oversubscribed five-year bond.