OpenHydro, a developer of tidal energy turbines, has raised €42.4m from DCNS, a French defence and energy group that is its biggest shareholder.
The Dublin company said the injection of funds was the first of two investments that would total as much as €90m.
The funding will be used to expand the business from turbine development into commercial production at several sites, according to Patrick Gougeon, chief executive of OpenHydro.
He said tidal technology had taken longer and cost more than expected to develop but was reaching a turning point. He said the funds would “secure the long-term sustainability of OpenHydro”, which employs 135 people.
Some Irish shareholders in OpenHydro are reported to be unhappy with the new funding, which valued the company’s shares at less than half the price of previous investments.