Recently got a smart meter, and registered on the ESB networks site to get the usage data. After collecting about 2 months of data I went through the exercise of figuring out if a day/night/peak, day/night, or 24h Smart Tariff (with and without “free” weekends) is best.
It was a bit of spread sheet work but well worth understanding which time of day we use most electricity, and if e.g Peak time usage would cause an issue, or the those ‘free weekend’ tariffs would make a difference.
it was also interesting to model how moving usage out of peak hours, or from day to night hours, would impact the bill.
In our case it was also clear that the only way to reduce the monthly bill to any useful extend is to overall reduce usage.
Ended up with a ‘standard’ 24h smart tariff (same rate all day) which is on offer from many providers. The benefit compared to a non smart tariff seems to be mainly that your electric provider receives the usage data directly and in “real time”, instead of 2-monthly or so readings. Which makes for much more accurate bills, and some providers will give you some useful usage analytics (so you don’t have to do your own spreadsheet)
YMMV - but It really depends on your usage pattern which tariff is most effective.
The smart meter or smart meter plan will not by itself increase your electric bill - especially if you select a 24h tariff.
I have reasonably accurate usage records since 2015, and my electricity usage hasn‘t suddenly jumped since the meter was replaced.
Electricity prices have gone up quite badly though, especially the last two years.
Reviewing the prices on your bill regularly, and moving to a cheaper provider whenever your contract ends is really helpful. The smart meter (and automated readings) do help with this.