Because my home is a "Nightsaver" home with night storage heaters/immersion representing c. 50-60% of my total electricity usage and, from what I could see, all smart plan night unit rates were much higher than on a traditional (legacy?) non-smart day/night tariff night unit rates so I would end up paying more on a smart plan. When I eventually have a year's worth of smart meter generated HDF data I will be in a better position to shop around properly using
https://energypal.ie/
Edit: On my current Energia day/night tariff my unit rate is 12.68c ex VAT. Last time I looked no smart plan night unit rate came anywhere close to that.
Edit 2: I just downloaded my HDF data to date (admittedly only a couple of months' worth so far) and energypal confirms that my existing Energia non-smart day/night tariff is cheaper than all available smart tariffs.
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