The Commission for Energy Regulation quotes " For accredited price comparison websites visit www.bonkers.ie or www.uswitch.ie." so I guess that's about as good as it gets.
My electricity supplier changed my tarif last week, as I had reached the end of the bonus period. I rang them up and threatened to move to another supplier. I was immediately offered a credit of € 150 on my account to stay with them for a further 12 months. This worked out as an even lower price than I had been paying, so I accepted. I will have to do the same again in 12 months, but that's the price you pay.