Testing on a potentially groundbreaking new technology in power generation is getting underway today in Strangford Lough.
The world's first commercial scale tidal power device has been erected in a joint venture between ESB International and Marine Current Turbines.
ESBI is investing €4m in MCT, the company that has designed and developed the tidal stream device known as SeaGen.
The prototype's turbines are simple propellors, mounted in pairs on a heavy pile sunk into the sea bed.
The propellors are driven by fast-flowing tides, generating potentially useful amounts of electricity.
Underwater maintenance is said to be expensive even in calm conditions and prohibitively difficult in fast tides, so the propellor assemblies are designed to be raised out of the water for maintenance or repairs.
The backers say the turbine blades spin slowly enough that they won't be a threat to sea life, and the company extols the zero-carbon, environmentally friendly nature of its power.
The 1.2 megawatt SeaGen turbine has been successfully deployed in the water and will generate one of the most environmentally friendly and sustainable forms of energy with zero carbon emissions.
It will be capable of providing enough clean electricity to power 1,000 homes.
However, Bernard Byrne Group Finance Director with the ESB says it will be some time before it becomes clear whether larger commercial scale tidal generation projects will be introduced over the coming years.