Dynamic Electricity Tariffs in Ireland

On a standard plan you pay one unit rate all day. On a smart time-of-use plan you pay two or three fixed rates depending on the hour. On a dynamic tariff the unit rate is rebuilt every 30 minutes from three parts:

• Standing charge. A fixed daily amount for the connection, billed annually between €299.75 (Energia) and €397.39 (Yuno, PrePayPower) on the plans below.
• Base unit rate. A fixed cent-per-kWh charge covering network costs, regulated charges and the supplier's own costs. Electric Ireland, Energia, Yuno and PrePayPower split it into day, night and peak bands; Bord Gáis charges one flat base rate of 16.73c in every half hour.
• Dynamic unit rate. The wholesale price for that half hour, which is what changes. It can be close to zero on a windy night and 30c or more on a still winter evening.

The base rate matters more than most people expect. Even when the wholesale price collapses to zero, you still pay the base rate for that half hour, so the floor on a dynamic plan is the base rate, not zero. Energia says this explicitly: the base rate covers fixed costs that do not fall when the market falls.

Every plan on sale requires a smart meter that reports half-hourly readings with a strong signal (a CTF score of 4, the top grade ESB Networks assigns to meter communications). Without that, the supplier cannot bill each half hour separately.

The dynamic component comes from the SEMOpx day-ahead auction, the power exchange for the all-island Single Electricity Market. Every morning, generators and suppliers submit bids for each half hour of the following day. The auction clears before 11:00 and publishes one price per half hour in euro per megawatt-hour. Divide by 10 to get cent per kWh: €175/MWh is 17.5c/kWh.

Bord Gáis states that its dynamic rate corresponds to the SEMOpx half-hourly price, and Energia sends customers to semopx.com when its own portal is down, so the day-ahead price on this page is the number their customers actually pay on top of the base rate. Electric Ireland, Yuno and PrePayPower say their dynamic rate reflects or is the wholesale price without naming the index. Bord Gáis prices the day from 23:00 to 23:00, so its Tuesday prices start on Monday night.

The price is set by the most expensive generator needed in each half hour. When wind covers most of demand overnight the price can fall below zero. When the wind drops on a cold evening and gas plants set the price, it spikes. Our wholesale electricity prices tracker shows the daily average back to 2018 and explains why Irish prices are among the highest in Europe.

Over the last 12 months the day-ahead price went negative in at least one hour on 4 days, and the single highest hour reached 46.6c/kWh on 25 November 2025. A dynamic tariff exposes you to both ends of that range.

• Winter evening spikes. Between 17:00 and 19:00 on a still, cold day the wholesale price alone can pass 30c/kWh. Add a peak base rate of 22c to 27c and you are paying 50c or more per unit for the hours most homes use the most. Yuno and PrePayPower quote a worst case of 82c/kWh at peak.
• The cap is not the same everywhere. Bord Gáis, Yuno and PrePayPower cap the dynamic element at 50c/kWh. Energia's cap is the SEM reliability option strike floor price, which changes weekly. Electric Ireland says a cap applies but does not publish the level. None of the caps apply to the base rate.
• Negative prices do not mean free power. You still pay the base rate in a negative half hour. Energia states that the negative price is netted into your dynamic cost, which is the most generous treatment we found published.
• Bills are unpredictable. You only know tomorrow's prices the afternoon before. Bord Gáis calls its plan financially risky and every supplier says it is unsuitable for vulnerable customers or anyone who cannot shift usage.
• Higher standing charges. Electric Ireland's dynamic standing charge is €328.58 against €250.77 on its EnergySaver 24-hour plan, a €78 a year handicap before you use a unit.

With no load shifting, the dynamic plan only undercuts the 24-hour plan when the average day-ahead price is below about 14.29c/kWh (€143/MWh). The 12-month average is 13.2c, below that line, so even a flat-profile home would have come out ahead over the past year. If VAT at 9% is charged on the dynamic component, add about €55 to the dynamic figure.

The saving is in the shifting. 17 September 2026 the cheapest hour is 12:00 at 2.3c and the dearest is 21:00 at 26.7c. Every kWh a battery or EV charger moves from the dearest hour to the cheapest one on a plan like this saves the wholesale spread plus the gap between the peak and night base rates, which for Electric Ireland is another 14.03c.

1. Check your meter. You need a smart meter with half-hourly reporting and a CTF (Communications Technically Feasible) score of 4. Your current supplier can tell you the score. If you do not have a smart meter yet, ESB Networks installs one free. Our smart meters in Ireland guide covers the rollout and what the meter records.
2. Pull a year of half-hourly data. Download your usage from the ESB Networks portal and see how much falls between 17:00 and 19:00. If it is more than a fifth of your total and you cannot move it, stop here.
3. Sign up by phone where required. Electric Ireland and Energia only sell their dynamic plans through their contact centres, and both want an online account set up first. Bord Gáis, Yuno and PrePayPower take online sign-ups.
4. Set a price alert. Energia and Bord Gáis will email or text you when tomorrow's prices pass a threshold you choose. Use it.
5. Automate the shifting. Put the EV charger, immersion and battery on a schedule that follows the published prices. A dynamic tariff managed by hand rarely beats a fixed smart tariff.