Wind energy provided more than 36% of the country's electricity last year, according to Wind Energy Ireland.
Its annual report published today, reveals that output increased from 32.5% in 2019 - making Ireland number one in the world for the share of electricity demand met by onshore wind.
While wind energy outperformed gas in the first and last quarter of 2020, Wind Energy Ireland said concerns are growing in relation to the rising amounts of 'lost' energy.
Their figures show that in 2020 this amounted to more than 1.4 million MWh of electricity, nearly double the figure for 2019.
This is just under 11.5% of total production and enough to power more than 300,000 homes
Wind energy is lost when EirGrid, as the transmission system operator, instructs a wind farm to produce less electricity or even to shut down entirely because the grid is not strong enough to cope with the volumes of power being produced.
Dr David Connolly, CEO of Wind Energy Ireland, said these levels of lost wind power must be replaced by fossil fuels.
"So every time wind farms are turned off, our carbon emissions go up.
"As we develop more wind farms, particularly the large offshore projects that are in planning, we are going to need a much stronger transmission system," he said.
Dr Connolly said Ireland needs to support Eirgrid's efforts to expand and strengthen our electricity grid.
"This support needs to extend right across the political system and wider society if we are to have any hope of decarbonising our electricity supply," he said.
Last year, Dr Connolly said eight new wind farms were connected to the grid with a combined capacity of 135 MW, while planning permission was confirmed for seven new wind farms with a capacity of 307 MW.
"Although there was a slowdown in the number of new projects connecting to the grid after a very busy 2019, the number of projects which got planning permission and the growing number applying today shows the strength of our pipeline.
"Last year also saw the first Renewable Electricity Support Scheme auction and the signing of new Corporate Power Purchase Agreements (CPPAs).
"This means we have more than 600 MW of new wind farms going into construction," he said.