SSE has posted significant half-year profits alongside record investment.

The Perth-based energy giant, which is one of the largest operators of electricity networks in the UK, posted adjusted profit after tax of £489 million, set against £162m, for the six months ending September 30, while it invested £1.7 billion, against £1bn last year.

It comes as the prospect of a windfall tax continues to be debated.

SSE invested £1.1bn in the first half in building and operating offshore and onshore wind farms, upgrading transmission and distribution networks to support increased electricity demand, and pioneering carbon capture and hydrogen storage technologies, it said.

A further £640m was invested in strategic acquisitions where SSE sees opportunities to deliver more clean infrastructure.

It comes as Chancellor Jeremy Hunt is said to be considering whether to increase the windfall tax on oil and gas giants from 25 per cent to 35% and also extending it to electricity generators like SSE.

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Alistair Phillips-Davies, SSE chief executive, said investment potential should be protected.

“In terms of levies, caps, windfall taxes, whatever that may be, if they’re fair and reasonable - fine,” he said. “I think one of the things we’ve got to be careful of in the UK is that we’ve created an amazing environment in which investors can come in.

“We’ve got one of the best green investment markets in the world, we’ve created the biggest offshore wind market in the world.

“It’s critical that we don’t endanger that, particularly when all of that investment is going to be delivering energy throughout this decade at far, far lower costs than we’re currently importing.”

HeraldScotland: SSESSE (Image: London Stock Exchange)

SSE said that if the investment needed to reach Britain’s 2030 electricity targets had instead been achieved by 2022, the country would have saved around £30bn on buying gas this year.

“The cheaper energy is coming. We just need the infrastructure; and SSE is building it at pace,” the company said.

Progress in the period included first power at Seagreen, Scotland’s largest and the world’s deepest tethered wind farm, and completing the first foundations at Dogger Bank, which will be the world’s largest offshore wind farm when completed.

The first 100km of subsea cable that will connect Shetland to the mainland electricity grid for the first time was completed, and the firm also highlighted the acquisition of Triton Power, adding to SSE’s pipeline of opportunities in emerging technologies.

It said first half earnings per share were in line with September’s pre-close guidance at 41.8p, while the board has recommended an interim dividend of 29p, which would be payable in March next year.

SSE continues to expect adjusted earnings per share for the full year of at least 120p – unchanged from May - with capital expenditure for the full year expected to be in excess of a record £2.5bn, including acquisitions.

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John Moore, senior investment manager at RBC Brewin Dolphin, said: “SSE has delivered another good set of results and has further outlined its plans to invest meaningfully in the future of the UK’s energy network.

“Given the macro-economic and political environment, it is prudent to continue emphasising the latter and the role SSE plays in delivering clean energy transition which is very much the narrative that will take the company forward.

“The shares are more or less flat on a year ago, recovering from the recent dip caused by the threat of a windfall tax on excess profits.

“But, SSE has seldom been more relevant to the UK’s direction of travel, backed by a solid balance sheet, investment programme, and a generous dividend for investors.”

Shares in SSE closed marginally up, 0.03%, or 0.5p, at 1,644p.