However, AEM said in a statement that hydroelectric energy production was 17% lower than historic averages due to hydrology restricting some operations.

In its financial report for the year to 31 December 2006, AEM said lower rainfall and the consequent “water emergency” from mid-year led to constraints on some production, such as those placed on the company by Lombardy regional government.

AEM added that the restrictions on energy generation in Lombardy and the need for changes in the management of reservoirs meant the output from the Valtellina hydro system could not be optimised.

For the coming year, the company anticipates economic advantages for its hydro portfolio from the greater availability of ‘green’ trading certificates due to investments made in the Valtellina hydro system.

Financial results were not broken out within the portfolio but at group level earnings before interest, taxes, depreciation and amortisation (EBITDA) nearly doubled to Euro1.4B from Euro718M in the previous period. Revenues jumped 133% to nearly Euro7bn.