German energy group Innogy plans to spend about €100 million in the Republic on building battery plants for storing electricity for use by homes and businesses.

Innogy last year announced that it was backing the Dublin Array wind farm project in the Irish Sea, which could cost up to €1.5 billion to build, and has also been working on several onshore developments.

Hans Bünting, chief operations officer of its renewables division, confirmed that it intends building three battery storage facilities in counties Dublin, Meath and Monaghan, as it continues to expand its Irish presence.

The three will have a total capacity to store 100 megawatts (MW) of electricity, enough to power about 100,000 homes. The facilities are likely to cost Innogy in the region of €100 million all told.

The batteries are the same as those used in electric cars. They store electricity so it can be released on to the national grid at times of high demand.

Mr Bünting noted that Innogy’s facilities would be located at points with easy access to the national grid.

Batteries are used increasingly across Europe as renewable electricity generators such as wind and solar farms take a growing share of the market.

Power from these sources is not always available at the precise time that it is needed, so batteries store the electricity as they produce it, releasing it as it is required, helping to “balance” supply and demand.

Mr Bünting said Innogy was stepping up investment in the Republic on the back of a Government commitment to boost the amount of electricity that comes from renewable generators over the next decade.

He pointed out that the Republic was already successful in this area. “About one-third of generation already comes from renewable sources, which is quite a lot,” he said.

Innogy is one of several players planning to install batteries on the Irish network in the near future. State-owned ESB is also eyeing investment in this technology, while Norwegian operator Statkraft is likely to be responsible for the Republic’s first ever such facility. It is working on an 11 MW plant in Co Kerry.

The German group is one of Europe’s biggest suppliers of renewable-generated electricity.