Kilowatt.ie Electricity Price Comparison Methodology

  1. For comparisons based on your kWh consumption or the national average, we assume the following split across times of the day:
    • 10% used during “peak” hours (5pm – 7pm)
    • 37% used during “night” hours (11pm – 8am)
    • 53% used during the remaining “day” hours (7pm – 11pm and 8am-5pm)
  2. For comparisons based on your kWh consumption or the national average, we assume that your average consumption is flat within each time band
  3. The “National Average” for calculations is 4,200 kWh per annum
  4. Where a tariff only has a single rate (24-hour), our platform sometimes refers to this as the “day” rate
  5. We assume you’re willing pay by direct debit and online billing if required to obtain the best price
  6. “Cashback”, “Welcome Bonuses”, and unit rate discounts are included in the calculations.
  7. It’s standard practice for electricity suppliers to jack up prices once your contract expires. To get a good value, you need to re-evaluate your options and most likely switch again as soon as your contract expires. Mark your calendar!
  8. All prices include VAT

Battery Simulations

Batteries are assumed to be AC-coupled, and have a round-trip efficiency of 87%, unless otherwise specified. Capacity refers to the usable discharge amount on the AC side per cycle.

We assume max charge/discharge rates according to the following table, unless otherwise specified.

Battery Capacity Assumed Max Charge/Discharge Rate
1 kWh1 kW
2 kWh2 kW
3 – 6 kWh3 kW
7 – 10 kWh4 kW
10-24 kWh6 kW*
>24 kWh11 kW**
*Approx single-phase limit
** Approx three-phase limit

EV Charging Simulations

EV charging is assumed to start at 2am each night, and continue until the the specified number of (AC) kWh have been consumed.

We assume that you charger runs at 7kW (AC)

For EV charging, all energy/power amounts refer to the consumption by the charger. This will be slightly higher than the energy delivered to the EV battery due to conversion losses inside the charger