Aggreko has won a contract to be the exclusive supplier of temporary energy services at the London Olympics in 2012, the power supply and temperature control specialist has announced.The value of the contract is expected to be around £37m. It will also be the sponsor of both the Olympic and Paralympic Games.The news will be welcomed by Aggreko, which has enjoyed a strong 2010, due in large part to events such as the football World Cup, but warned that about £90m in revenues from major events will not recur in 2011. Aggrekko said last week that it now expects a pre-tax profit of around £305m for 2010, up from its estimate of £300m in October. Trading was 'better than anticipated' in the fourth quarter, the company said.