The boss of international energy supply chain giant ASCO group which has a southern North Sea base in Great Yarmouth said a strong finish in 2011 had carried into this year as levels of confidence in the industry increased.

In its 2011 results published yesterday the company made a pre-tax loss of �10.8m as a result of one-off charges relating to a deal which saw Doughty Hanson acquire the company on December 31 2011.

But ASCO saw its revenue increase from �516.7m in 2010, to �626.5m this year.

ASCO Group, which also includes North Walsham-based waste management company Enviroco, saw its EBITDA (earnings before the deduction of interest, tax and amortisation expenses) increase from �29.2m to �30.1m.

Group chief executive Billy Allan said: '2011 will be viewed as perhaps the most significant in the history of ASCO. We secured substantial additional investment which will allow us to continue with our ambitious 10 year growth plan and grow to double our current size.

'The year also saw an increase in the levels of confidence throughout the industry although the impact of the prior year's downturn continued to drag on our activities during the early part of 2011. Generally we saw a strong finish to 2011, and this has continued into 2012.'

He added: 'The world's demand for energy continues to grow and this opens up new opportunities for our industry as a whole and ASCO in particular, as our clients focus on less accessible areas of exploration and production in order to satisfy demand – deep sea deposits, oil sands and shale oil all become viable at commodity prices that, by all accounts, seem set to remain at relatively high levels.'

ASCO established its Great Yarmouth base in the mid-1980's to support the Southern North Sea Gas Basin and subsidiary Enviroco has a waste transfer and treatment centre in Great Yarmouth and an industrial services centre in North Walsham.