These enhancements by the Electricity Alliance Central will mainly involve the design, construction and commissioning of 400kv and 275kv transmission substations.
During the contract extension, which runs until 2016, individual contracts will continue to be awarded based upon project scope, location, continual delivery and cost assessment.
For this reason the contract extesnion has no contract value.
The EAC was established six years ago as one of National Grid’s preferred Alliance partners for substation development and construction projects.
It operates in National Grid’s Central region, comprising the Midlands, Greater Manchester and Liverpool.
This original award was part of a programme worth up to £2.8 billion to upgrade and develop the electricity transmission network across England and Wales.
Paul Smith, Chief Executive of Morgan Sindall Group plc, said: “We are excited by this opportunity to continue to work alongside our Electricity Alliance Central partners to deliver complex substation projects which play a vital role in delivering high voltage transmission infrastructure in the Midlands and North West England.”