The EU cash will enable the device to be manufactured and ready for use in 2012.
Once installed, it will generate clean electricity from the tides off the west Wales coast.
Mr Jones said that investing in renewable energy was key to building a low carbon economy in Wales.
The £11m DeltaStream device will be sited on the seabed in Ramsay Sound, Pembrokeshire.
It will generate electricity from tidal currents via three turbines and promises to have a minimal impact on the environment.
Mr Jones said: “Investing in renewable energy technologies is vital to build a low carbon economy and help drive forward Wales’ ambitions to become a more sustainable nation.
“We are committed to promoting the generation of clean electricity while protecting our natural environment.”
The funding also provides support for Welsh marine renewable energy company, Tidal Energy, which has developed the device.
Managing director Martin Murphy, said: “This funding announcement comes at a pivotal stage in the project, and will provide Wales with a unique opportunity to develop and demonstrate a home-grown tidal stream technology.
“The next step for the scheme will be the manufacture of the DeltaStream device, ready for installation in 2012.
“Procurement for the fabrication and installation of DeltaStream is underway and the project will create a significant number of green jobs.”
On Tuesday, Mr Jones is also visiting the National Trust Stackpole Estate in Pembrokeshire where work is being carried out to upgrade the visitor facilities.