Peak demand in Ireland is ~4800Mw while minimum demand is ~2000MW and total generating capacity of ~6800MW. Peak load plants which can cope with short term variation and respond in minutes. Hydro and open cycle gas turbines are most common. How can we off set the use of these into the future as gas prices will rise and no more capicity for large scale hydro? Building new power storage plants seem to be the best option. Most obvious type to expand would be pumped hydro.