The air-conditioned comfort of the art-deco ballroom on the third floor of the Waldorf Astoria provided guests with a welcome respite from an early summer New York heatwave.

Business leaders, government ministers and ambassadors were among 800 people gathered at the famous hotel on Park Avenue to celebrate Ignacio Galan, chairman of Spanish utility Iberdrola, being named businessman of the year by the Spain-US chamber of commerce.

Under his stewardship, Iberdrola has grown from a successful Spanish company into a global energy giant in a few short years. Galan’s eye for an opportunity led Iberdrola to buy ScottishPower last year for £12 billion, and he has been on the prowl for more — such as British Energy.

A world leader in renewables, Iberdrola also has nuclear power stations in Spain, and as Britain increasingly turns to nuclear for its energy needs, Galan wants a slice of the action, though not at any price. Earlier in the day, as temperatures nudged 100F, Galan stayed distinctly cool and collected as he turned some heat of his own on the British nuclear generator.

British Energy had just rejected a takeover offer in the region of 680p a share, from French energy firm EDF. It suggested that 735p a share was more appropriate.

Everyone sat back waiting for a bidding war to begin with Iberdrola, until the erudite chairman pulled the plug. He said what British Energy wanted had made it too expensive, so he would look for opportunities elsewhere. Galan has a reputation as a tough cookie and his decisiveness has been one of the driving factors in Iberdrola’s rise. It still came as a bit of a shock.

“The price is very, very far from what we think is reasonable,” he said, expressing anger at one report that had falsely suggested Iberdrola had actually agreed an 885p-per-share deal with BE.

“Our stock fell 3% after that,” Galan said, making it clear as to why he had to move quickly to prevent further speculation from knocking the company off its long-term growth strategy.

Galan has been at the heart of those plans for seven years now. Accepting the award, in near-perfect English Galan took dinner guests through the story of the company’s recent rise. It was the world’s leading wind-power firm, he said, but while renewables were the way forward, they were not the only way.

He named America as his “No 1 priority” for growth, and spoke of the billions of dollars Iberdrola had invested and would continue to invest there. But his toughness came to the fore when he reminded US regulators that if they delayed Iberdrola’s efforts at buying the East Coast power supplier Energy East for much longer, “other opportunities” were certainly available.

The $4.5 billion (£2.3 billion) deal was agreed last June but awaits one more approval. The US agencies are traditionally slow to convince. The ScottishPower takeover took five months, but would have been three months if the US authorities had not been involved.

If approval finally comes, Iberdrola will be a £50 billion company, and that could signal the start of further expansion into America, something that is easier with ScottishPower under its wing.

In a busy week, the former UK head of retail at Eon, Nick Horler, replaced Jose Luis del Valle, Iberdrola’s strategy and development director, as the chief executive of ScottishPower. Del Valle is one of Galan’s closest aides and he remains a key figure in the company.

The UK and US businesses will now operate under del Valle with a small board that includes Horler. Del Valle said the US-UK axis was important and that while Iberdrola remained committed to local teams running their own areas, there would be opportunities for the UK to play its part. Back on the home front, it might be out of the running for British Energy, but it still wants a part of Britain’s nuclear future. “ScottishPower has no nuclear experience, but Iberdrola does,” said del Valle.

Entering the UK has also given Iberdrola an advantage at home, where a heavily regulated and uncompetitive market is slowly opening up. Del Valle said Iberdrola has seen at first hand how it works in the UK hothouse, and will use this to its advantage in Spain.

Galan remains an enigmatic figure for many. He was repeatedly quizzed by Spanish journalists on why he extolled the virtues of the market, even though he admitted frankly that it meant that someone might one day come in and take over Iberdrola, at the right price.

“The market is good; the market works,” he said, adding he was hopeful that a greater liberalisation of the European energy market will see the end of the protection Iberdrola’s French and German rivals enjoy. But it was clear he has no intention of seeing the company, which some view as Spain’s national champion, disappear on the cheap or even at all.

Iberdrola has quietly become the world’s fourth-largest electricity company by market capitalisation. It successfully floated its renewables arm while retaining a major stake, and last week signed a strategic partnership worth £5 billion with turbine maker Gamesa to jointly develop wind projects.

Slipping under the radar is something Galan also seems to do well. Perhaps he wants the company to be underestimated. Its entry into the UK with the audacious ScottishPower takeover still left many in the UK oblivious to Iberdrola’s success and global aims. Staying invisible in the States will now be more difficult — the Americans know the Spanish are on their way.

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