Alness based wave energy developer AWS Ocean Energy said yesterday it had secured additional investment believed to run into millions.

The cash, which will be ploughed into its Archimedes wave-swing project, is coming from the Shell Technology Ventures (STV) Fund and the Tudor investment fund.

The value of the investments are not being disclosed, but the Shell fund is understood to be putting in more than £2million and Tudor less than £2million.

The money, coupled with the Scottish Government's £2million grant made to Alness-based AWS last year, will help the commercial development and deployment of the Archimedes wave-swing, said to be the world's first submerged wave-energy system.

AWS was set up in 2004. It employs 11 people and is looking to add to its workforce.

Simon Grey, chief executive of AWS, said: "The investment made by STV Fund and Tudor is a significant step forward for the company and the wave sector as a whole.

"Having their backing, alongside the Scottish Government, is an endorsement of what we have achieved so far and important for our future plans. This new investment will allow us to continue building our technical team where we have some really exciting opportunities opening up."

Mr Grey said his team will deploy a demonstration 250kw pre-commercial prototype of the wave swing at Orkney's European Marine Energy Centre in 2009.

This is expected to lead on to the first phase of a commercial demonstration farm in 2011, which may expand to 100 units within three years.

The STV Fund, which is managed by Kenda Capital, focuses on renewable energy technologies that show significant promise of delivering cost-competitive energy.

It chose to invest in AWS Ocean Energy after a detailed evaluation of the international marine energy market.

Aruna Subramanian, investment principal at Kenda Capital, said: "While recognising the vital contribution the oil and gas sector makes to the world economy, the development of new energy technologies is crucial if we are to address the challenges of energy security and environmental responsibility."

As part of the investment deal, the AWS board of directors will be joined by Ms Subramanian; Terry Rhodes, Shell's head of offshore structures; and Ahmed Moussa, former general manager of Gamesa, the Spanish wind-turbine maker.

Welcoming the new directors to the board, AWS chairman John Anderson said: "Not only will we benefit from the considerable experience of the new directors, but this latest investment recognises the great work of the talented team at AWS and will provide the resources to attract more talent to the company to help grow AWS as a leader in wave energy."

In addition to the new investments, RAB Capital - one of the existing AWS shareholders which first invested in April 2006 - will further increase its stake in the company as part of an arrangement that sees the exit of some founder shareholders.