Shares in Aggreko were up on the FTSE 100 in morning trading after the generator hire company reported a "strong start to the year" in the period from 1 January to 31 March.

Group revenue in the period was up nine per cent, excluding revenues from major events such as the Vancouver Olympics and the Asian Games.

The group's International Power Projects division saw revenues rise 19 per cent. The group signed a number of "notable orders" in the period in the Bahamas, Argentina, Oman and Indonesia, in addition to a year long contract with the Tokyo Electric Power Company, which is currently dealing with the ongoing crisis at the Fukushima Dai-ichi nuclear plant..

Local business revenues in the period were broadly similar to the same period in the previous year. On an underlying basis local business revenues rose 18 per cent.

Group net debt rose £63 million to £195 million in the period, thanks mainly to higher capital investment by the company. Aggreko said it was proposing a return of capital to shareholders of £150 million in July.

The company's Chairman, Philip Rogerson, said he would be retiring from the board in a year's time. He will be replaced by independent non-executive Ken Hanna, who is also the current Chairman of Inchape Plc.

In an outlook statement Aggreko, said, "The strong start seen in the Local business is encouraging, but as always the performance for the year as a whole will be heavily dependent on trading during the summer months. Despite political instability in a number of our markets, International Power Projects has also had a good first quarter; in the light of the strong order intake in recent months, and the healthy pipeline of enquiries, we plan to increase the rate of our fleet capital expenditure in the second half by about £70 million, and to spend around £390 million across the Group as a whole during 2011.

"As a result of movements in the US Dollar : Sterling rate, we are now applying a rate of 1.60 to our forecasts for 2011, rather than 1.56 used at the time of our 2010 results announcement. The impact of this is to reduce anticipated full year trading profits by around £7.5 million. Despite this adverse exchange rate movement, we now expect trading profit for the year to be slightly ahead of 2010, which would represent underlying growth in constant currency of around 20%."

By 11:10 shares in Aggreko were up 4.74 per cent on the FTSE 100 to 1,791.00 pence per share.