Harkeeret Singh, head of data centre strategy at BT, said data centre growth is possible in London but limited power supply means new centres need to be planned six to 18 months in advance.
He said: "The power companies do not have the power available immediately. People have got to accept there is a long lead time required to make provision for power consumption.
"In the short term there is a lack of supply of data centres but there are a lot of developers bringing on space in the next couple of years."
TelecityGroup is a major provider of data centres, running 18 centres across Europe - seven in London - and will complete two further centres in London and Amsterdam this year.
Its customers include Virgin Radio, T-Systems and Transport for London.
A spokesman for TelecityGroup, said: "There is a big infrastructure commitment coming into the Olympics. It might be a limiting factor for companies without the necessary experience to build a data centre in London."
He added: "But we have not found it to be a problem, it is all about having the right planning and relationships in place in advance."
He said that customer demand for data centres based in London remained high, fuelled by a desire for low latency and co-location with existing offices.
The electricity supply for London is provided by EDF Energy Networks and a spokesman for the supplier said the company is projecting an investment of about £2bn in its three networks between 2005 and 2010 and completes 100,000 new connections to its networks each year.
The EDF spokesman said: "The company takes into consideration future load growth, something particularly important in areas of rapid expansion such as the City of London and Lea Valley.
"This is why we work closely with organisations such as Berr [Department for Business, Enterprise and Regulatory Reform], the Greater London Authority, the Corporation of London and large developers to ensure we have an understanding of future demands and their requirements regarding any power needs."
He added: "We operate the network in compliance with our licence and also have robust monitoring equipment which tracks the demand for power and indicates where reinforcement is necessary - long before it becomes an issue. Our works in connection with 2012 [Olympics] are not delaying any other projects."
He advised businesses to contact EDF early on when it expects its power demands to increase.