Use a current transformer.
In the simplest form, you can just use any toroidal inductor. Then for the primary winding use thick (insulated) copper wire and make a few loops trough the toroidal core. The original winding of the inductor then becomes the secondary winding of the current transformer. You should short circuit this with a low impedance (for example 10 to 50 Ohm) Then you can amplify the resulting signal with an opamp, rectify, peak detection, or do other further processing.
You can also easily create double isolation by adding a heat shrink tube over the already insulated primary wire.
This setup is ideal for hobby-ing and experimentation, as the exposure to mains voltage is very minimum.
This does have always active electronics on the secondary side. This can be prevented, depending on the current transformer you use. It's possible to tap off enough energy though the current transformer to switch some other circuitry.
You can also use a regular mains transformer, and use it as a current transformer by putting the secondary winding in series with your load. In that case you have plenty of energy to connect an external circuit (even directly putting an 24Vac relay on the 230V winding may work)
There are a few gotcha's which make this approach non-trivial.
* The secondary winding must be able to handle the current of your 2.2kW load (which is about 10A).
* The High voltage output must be connected to a low impedance (12Vac or 24Vac relay may work).
* You could have too much energy pushing though the transformer, which may overload your "relay".
* There is more potentially hazardous wiring.
* It may be necessary to rewind a transformer. For example a 230V to 6V 2A transformer, then remove the secondary and put thicker wire on it to handle 10A.
With a toroidal core the energy output will be much lower, but it's probably enough to drive an "optomos" relay. And the output of an optomos relay is strong enough to drive the gate of a triac.
But using an "always on" power suppply would make it easier, and these can be quite low power too.