Telstra says it will split itself into three separate legal entities.

Telstra CEO Andrew Penn has announced the company's “biggest and most complex” restructure since its privatisation almost 20 years ago.

It will see the company split into three separate legal entities operating under an umbrella Telstra Group.

One firm will be InfraCo Fixed, which owns and operates Telstra's physical infrastructure assets (ducts, fibre, data centres, subsea cables and exchanges). Another company will be called InfraCo Towers, owning and operating Telstra's physical mobile tower assets. The third is ServeCo, which is being created to own and operate Telstra's retail business.

“Telstra intends to start seeking investment from third parties while maintaining control of our strategic towers and preserving our competitive differentiation for Telstra's mobile business,” Mr Penn said.

“We anticipate this will begin in 2021 and will follow a similar timeframe to the rest of the restructuring process.

“There are a range of commercial, regulatory, and operational requirements needed to finalise the structure, including consultation with our employees and unions.”

Mr Penn said Telstra would also push into renewable energy.

“We are exploring the opportunity to re-sell energy to our consumer customers,” he said.

“These plans are at an early stage but we are about to apply for the necessary licences and you will therefore be aware of them in coming weeks.

“We are one of the largest consumers of electricity in the country and we have been heavily involved in the sector by underwriting renewable energy via power purchase agreements (PPAs), providing firming power capacity during times of extreme demand or grid instability, and neutralising the emissions from our total operations.

“We already underwrite projects that generate enough renewable energy to power about 100,000 homes, and we provide standby power that enables more renewable energy to be absorbed into the energy grid.

“We deploy machine learning and Internet of Things (IoT) to change the way we use energy. We also have a very experienced energy team.

“All of these things help us affordably access more renewable energy, and we also help some of our large customers do the same.

“We are exploring bringing this experience to the table with a consumer offer leveraging our strong in-home position with our customers, the investments we have made in the digitisation of our customer systems and our Telstra Plus loyalty program.

“We plan to do so with a simple affordable solution at a low cost for us.

There is also widespread speculation Telstra is positioning to buy the National Broadband Network in coming years.

Mr Penn said InfraCo could bid for a privatised NBN Co in coming years, but it would hinge on NBN Co generating positive cash flow.

Current legislation prevents the NBN being owned by a company which is also a retailer of telecommunications services.