SEC24 KWH230 energy meter at EUR 22.99: enter your own rate and it shows money, not units

Every article about saving electricity ends at the same sentence: multiply the watts by the hours. The problem is that nobody actually knows what their old fridge, old tumble dryer or old router draws, because the number on the rating plate is the maximum, not what it uses day to day. The SEC24 KWH230 is the cheapest tool that closes that gap, at EUR 22.99, rated 4.5 from 51 reviews, listed by bol as in stock with next-day delivery when ordered before 23:59. It is a pass-through socket: the wall feeds it, the appliance plugs into it, and the display reads volts, amps, watts and accumulated kilowatt-hours.

The genuinely useful part is the second function: you can enter your own per-kWh contract rate, after which the display shows money rather than units. That does the arithmetic for you, though the sum is simple enough to do yourself: watts divided by 1000, times hours, gives kilowatt-hours, times your rate. The manufacturer also notes that kilowatt-hours are always shown whether or not you enter a price, so both ways work. To decide whether an old appliance is worth replacing, leave it plugged in for a week, read the accumulated total and multiply by 52 for a year.

• A pass-through energy meter reading volts, amps, watts and cumulative kilowatt-hours, up to 3680 watts. (source 1)
• You can enter your own per-kWh price and the display then shows cost; without a price, the kilowatt-hours are still shown. (source 1)
• EUR 22.99, rated 4.5 from 51 reviews (45 of them four or five stars), listed as in stock with next-day delivery before 23:59. (source 1)
• The manufacturer states plainly that it suits the Dutch market only: Belgian sockets use an earth pin and it will not fit. (source 1)

That Netherlands-only line deserves its own paragraph, because it is the most common reason this category comes back. Dutch sockets earth on side contacts, Belgian ones on a pin; they look close and do not fit. The same seller makes a separate French and Belgian version, the KWH230FR, at the same EUR 22.99 and the same 4.5 rating, so for anyone living near the border the cost of the wrong choice is not money but a return trip through the post. Look at your own socket for a metal pin in the middle before you order.

It is worth being clear about what it cannot measure. Being a plug-in device, it only reads appliances whose plug you can pull. Underfloor heating, an electric boiler, an induction hob or a built-in oven are wired to the consumer unit and cannot be connected to it. Anyone who wants whole-house totals needs the type that reads the meter's P1 port, and in the same set of results that kind is EUR 21.50, rated 4.6 from 28 reviews: EUR 1.49 cheaper, but it reads the whole building rather than one appliance, which is a different question altogether.

Price

EUR 22.99 (bol.com, checked 9 September 2026)

Rating

4.5 out of 5, based on 51 customer reviews

Specs

SEC24 KWH230 pass-through energy meter, LED-lit display, measures volts, amps, watts and kWh, up to 3680 W, EAN 8719325304640

Platform

bol.com, listed as in stock with next-day delivery when ordered before 23:59

Checked

Price, rating and review count read from the listing and the bol catalogue interface on 9 September 2026

Hokimi field note: measure for a week before deciding to replace an appliance; it beats estimating from the rating plate.