Plans for 420 solar farms rest on State backing
Developers are planning to build more than 420 solar farms nationwide capable of powering more than 2.1 million homes.
The ESB said it had received applications to connect with the grid, which would provide more than 2,500MW of power - more than the amount of wind energy currently on the system - and that interest was at "unprecedented levels".
But developers have warned that the lack of government support is hampering development.
Former Bord Gáis boss John Mullins told the Irish Independent a tariff or guaranteed payment for solar energy was needed to drive investment.
While there are financial supports in place for wind, biomass and hydro - and for peat, which is a major driver of climate change - there is none for solar.
Photovoltaic solar (solar PV) panels convert daylight into electricity.
When the light strikes a panel, an electrical current is generated. The power is fed to the electricity network, and used across homes and businesses.
The interest in solar comes amid mounting opposition to wind farms, which are needed so Ireland can meet a 2020 target to produce 40pc of all electricity from renewable sources. Around 19pc is currently generated from wind, with 2,400MW installed and another 1,400MW needed.
Mr Mullins, chief executive of Amarenco, said that solar could deliver the required energy if a tariff was introduced.
"Why do all other countries have solar PV and we don't?", he asked.
In a statement, the Department of Communications, Energy and Natural Resources said a new renewable electricity support scheme was being designed, and that the potential of solar PV was being assessed.