The National Digital Park in Dublin's City West Campus has suffered a power failure after a high-voltage cable was accidentally severed, cutting power to more than 100 high-tech companies.
Power into City West - where many communications and Web-hosting firms are based - is likely to be restored shortly, according to an ESB spokesman.
The National Digital Park aspires to become the hub of broadband technology (developments to dramatically increase the speed of Internet access and use) in Ireland.
While many firms in the area were seriously affected by the outage others used emergency generators to maintain services.
The ESB spokesman said there are up to 20 such power outages a week because of work being carried out by contractors.