Metronode, which operates computer data centres across the country, has lodged hundreds of pages worth of reports with Wollongong City Council outlining its vision for the state-of-the-art, environmentally friendly South Coast centre.

The documents state the development would include three buildings housing technical space, plant rooms and "data halls" storing sensitive computer information primarily for the NSW Government's finance department.

A second facility would be built at Silverwater, the Government has said, with both complexes expected to be operational by the end of 2013.

The Unanderra hub would create around 50 new jobs, Finance Minister Greg Pearce said previously.

Metronode general manager Malcolm Roe yesterday welcomed the start of the development process, saying a construction crew of 250 would be working on the buildings.

"We are looking forward to the development of this key infrastructure in the region and contributing to developing the Illawarra region as a data and technologies hub for the state," he said.

However, the planning documents are likely to be the only glimpse residents will have of what will be constructed inside the buildings, with Metronode confirming stringent security measures will be put in place to ensure complete control over access is maintained.

"The security level of the data centre is one of the key requirements of all Metronode's clients," planning reports said.

"All Metronode data centres have stringent security measures to meet its clients' requirements and the measures seek to reduce the likelihood of threat, to minimise impact arising from any breach of security [and] to provide effective deterrent to potential threat."

Security measures set to be put in place include 3m-high fences surrounding the 1.86ha site and six security zones from the external perimeter through to the data halls, designed to provide a "defence in depth" approach.

The centre will feature the latest data storage technology system, which uses fresh air to cool the computers and servers, unlike traditional data centres that rely on around-the-clock air-conditioning.

The system, the first of its kind in Australia, would significantly reduce energy and water demand, Metronode's environmental report to the council said.

The Joint Regional Planning Panel would be responsible for determining the proposal.

If approved, construction of the storage facility was expected to begin in September.