Hi Dancewithme,
Electric Ireland just looks after the billing side of things (in 2004, ESB became ESB Customer Supply and ESB Networks - then in 2011 ESB Customer Supply became Electric Ireland).
Storage heaters can be purchased from different manufacturers. ESB promoted the NightSaver (the meter that has a day rate and night rate - and the significantly lower night rate is ideal for storage heaters or electric vehicle chargers).
Kind regards,
Una